UAH has posted its TLT July anomaly as +0.85ºC, up on June’s +0.80ºC. This is also up on July 2023’s +0.64ºC, making UAH’s July 2024 TLT anomaly the hottest July on record.
Some SAT records may also manage to show July 2024 as ‘hottest on record’ but so far the re-analyses (CDAS and soon ERA5) are/will-be showing July with a higher anomaly than June’s but below July 2023.
[Response: This is a little interesting. We know that MSU TLT has a larger fingerprint from El Niño than the surface records (cf. 1998 etc.), and so this is evidence that the spikes seen in the surface records last summer/fall were not (wholly) driven by the emerging El Niño… – gavin]
Now is a good time to review the work of erstwhile chief scientist James Williams of NASA JPL on the strongest lunar forces. Plug those in and good things will happen in modeling El Nino,
This is a huge power addition due to the application of information technology. Everyone is grabbing a piece of the ever expanding pie:
“Folks, we aren’t talking about this enough. There are *5 gigawatts* of data centers in engineering phase on the ComEd grid right now, and ***13GW*** more in waiting.
This would DOUBLE the peak load on our grid in Northern Illinois.
Quintillion calcs/sec burns lots of CPU cycles to predict climate, a slight +feedback to the climate change problem. Yet, if a modern CPU is 10-20 GigaFLOPS/watt, a Quintillion FLOPS computer would use 100 MEGA watts of power. So if a hairdryer is 1000 watts, this is 100,000 hair dryers using power in parallel. Substitute that many microwave ovens, vacuum cleaners operating for days at a time. That’s the context missing from the AGU article linked above.
Let’s see if we can compute smart and not hard, as with https://GeoEnergyMath.com.
Likely, breakthroughs will be in understanding the nonlinear fluid dynamics, not in wasting CPU cycles going down a path that leads to the wrong answer.
The last possibility is what (Andrew) Dessler calls “weirdness.”
The Earth’s climate is incredibly complex, and there’s some natural variability in temperatures on short time scales like one or two years. A few extra tenths of a degree of heat in the Atlantic due to nothing more but natural variability could account for a couple of record-breaking years, when it’s layered on top of warming from climate change and El Niño.
“My guess is, in the end, it’s just going to be internal variability,” Dessler explains. “Like, something weird happened! Because the climate’s always doing something weird.”
So, the scientific explanation is “weirdness”. In this case, weird is a euphemism for “we have no idea”. Related to the observation of the experimental scientist who exclaims: “I’ve never seen that before”.
As long as the jury is still out and weird is now under consideration, I will once again offer the nonlinear modulation of forcing which cross-validates indices such as ENSO and AMO. The formulation is weirdly unconventional but it does obey the primitive shallow-water wave equations used in modeling the ocean’s fluid dynamics. As with quantum mechanics or the theory of relativity, non-intuitive weirdness is a small price to pay for creating a correct model of observed behavior.
Consider quantum mechanics plus the extra non-linear weirdness of Fermi resonance, which in a recent paper by Wordsworth et al appears to be a significant factor in the GHG properties of CO2:
“Fermi resonance occurs in CO2 because ν1 ≈ 2ν2: The symmetric stretch frequency happens to be very close in value to double the bending frequency. As a result, nonlinear interactions between the two modes shift the energy levels of states ∣1000〉 and ∣0200〉 and cause their wave functions to mix”
CO2 is a linear molecule, so it does not have the strong GHG properties of the “bent” geometry of H2O. Yet, because of the stretching modes of the CO2, a pair of CO2 molecules can combine forces and induce a bending mode that would normally not get excited if the quantized sum of energies didn’t match so closely.
So, Fermi resonance is a phenomenon that occurs when two vibrational modes in a molecule are nearly degenerate (i.e., have similar energies) and interact strongly. This interaction can lead to a splitting of the energy levels and a redistribution of the intensities of the vibrational modes.
In the case of carbon dioxide (CO₂), Fermi resonance typically involves the interaction between the stretching modes and the bending modes. CO₂ has two primary stretching modes:
Symmetric Stretching Mode: Both C=O bonds stretch and compress in unison without changing the bond angle. This mode is generally inactive in infrared (IR) spectroscopy because it does not create a dipole moment.
Asymmetric Stretching Mode: One C=O bond stretches while the other compresses, changing the bond angle and creating a dipole moment, making this mode IR active.
In addition to these, CO₂ has a bending mode where the molecule bends out of its linear shape. (Here it will appear more like H2O)
Fermi resonance in CO₂ can occur between the first overtone of the bending mode and the asymmetric stretching mode. The bending mode has a fundamental frequency, and its overtone (second harmonic) can come close to the energy of the asymmetric stretch. When the energy levels of these two modes are close, the overtone of the bending mode and the stretching mode can “mix,” resulting in two new energy levels: one higher and one lower than the original energy levels.
This resonance causes a shift in the observed frequencies and an alteration in the intensities of the absorption bands in the IR spectrum. The Fermi resonance allows the bending mode to become IR active when it might not have been otherwise due to the quantized sum of energies aligning.
So when two CO₂ molecules interact, they can enhance this effect. The combined forces of the molecules can induce a bending mode that would normally not get excited if the quantized sum of energies didn’t match. This results in a coupling that redistributes the vibrational energy, leading to a Fermi resonance that can be observed spectroscopically. And the more the quantized energy levels, the more that a molecule can have a GHG effect by creating a sideband that exists within the IR spectrum .
No one really “understands” quantum mechanics, one just has to accept the arcane rules of quantized energy levels and structural symmetry, Same thing happens in fluid mechanics at a large scale. And once climate scientists look into the nonlinear interactions of waves, the sooner they will be able to model standing-wave phenomena of ENSO, and the sidebands that can occur from mixing constrained by the allowed wavenumber states within the oceanic waveguide.
Shows the importance of the standing-wave nature of the oceanic indices. As the thermocline sloshes in subsurface depth, different parts of the ocean show different surface temperatures, indicating proximity to heat or cold.
The interesting aspect is the concurrent appearance of Pacific La Nina conditions with Atlantic Nina conditions. These are now in phase, much like the tropical instability waves (TIW) always appearing in the Pacific and Atlantic during Nina conditions. TIW are invariably 1100 kilometers in wavelength and show up because the cooler below-thermocline water approaches the surface and so is more highly delineated as the long-period tidal forces modulate the low-effective gravity interface.
1) Re recent arguments that we can feed 10 billion people and hence can be indifferent to population growth, a recent article in Nature notes how large amounts of greenhouse gases are produced by the production of the synthetic fertilizers that modern agriculture uses in massive amounts. I.e., the creation of agriculture’s inputs are a problem, not just agriculture’s own emissions.
2) Plus the last time I checked those massive farming machines don’t run on sunlight.
3) The US Midwest feeds much of the world — but the huge Ogallala Aquifer used for irrigation is being depleted — which will put us back into the Dust Bowl.
4) Good intentions are no substitute for knowing how the chainsaw works.
Secular Animistsays
Don Williams wrote: “the last time I checked those massive farming machines don’t run on sunlight”
Tractors and other farm equipment can easily run on electricity generated by sunlight. Some reading for you:
1) From your citation:
“According to a March 2024 news release by MarketsandMarkets™ the electric tractor market is projected to grow from USD 0.7 billion in 2024 to USD 3.4 billion by 2030.”
3) Not only do electric tractors have (and will have) a very paltry market share, look at how electricity to fuel them is generated in the US Midwest. While wind has gained, much is still generated from natural gas and coal.
Don, you appear to be mixing apples with walnuts–a great combo for salads, but not comparisons. SA’s cite suggested exponential growth in the US electric tractor market, via a nearly 5-fold increase in 6-7 years; yours counters with a *global* market projection, which moreover is not broken down by technology. Thus, your claim that “electric tractors… will have… a very paltry market share” is unsupported. (Particularly since–if you believe both sources–the growth rate of electric tractors, in the US at least, is clearly much higher than the overall tractor market growth rate–that implies rapidly increasing market share for electrics.)
Can’t see your NYT source, as it’s paywalled, but just to highlight the “gains” of wind, the three states with the largest proportion of wind generation are Midwestern:
And maybe it’s worth mentioning that IL produces 54.15% from nuclear, and that both MN and MI have adopted 100% clean energy laws.
But that’s just a snapshot of today’s conditions: RE is gaining share by an exponential trend. Those state RE shares are going to be higher next year, and every year thereafter, for the simply reason that RE is now the rational economic choice in most instances.
We’ve frequently decried the inability of humans to cope well with exponential change rates,* which have made it difficult to understand the danger we face under climate change. But this likewise makes it difficult to appreciate the speed with which the energy transition is now happening.
*Over the longer term, the trend will not be an unbounded exponential one; it will follow something closer to the classic S-shaped ‘logistic curve.’ But we’re not there, yet; we’re now in the rapid acceleration phase.
Don Williamssays
1) I believe that the source cited by Secular Animist gave the electric tractor market size in 2030 of $3,4 billion for the ENTIRE GLOBE, not just the USA. Which would indeed be a paltry share of the $114,5 Bil market projected for 2029.
SA’s source may be optimistic for electric tractors — another source projects a market of only $0.9 billion even by 2032.
2) An even greater negative force is capitalism’s strong insistance on continual growth — which in turn demands continual population growth. See Elon Musk, etc. Or , in addition to the reference I gave above, see the recent article in The Atlantic mag of Laurence Jobs (Apple):
Kinda hard to maintain Social Security, Medicare , enormous interest payments on $35 Trillion in federal debt while also spending $Trillions in a Cold War 2.0 nuclear arms race unless you have high growth in population. The billionaires who actually run the USA know that.
The American lifestyle is not known for its small carbon footprint.
#1 You’d have a point in regard to #1 if it didn’t rely on the tacit assumption that only the US is developing electric tractors. But that assumption, luckily, is counterfactual.
Some of the primary industry players from the Asia-Pacific region include Yanmar Holdings Co. Ltd, YTO Group, Kubota Corporation, TAFE, ITL, Sonalika, HAV, and AutoNXT Automation Pvt Ltd. Overall, the Asia-Pacific region presents a promising future for the electric tractor market due to a combination of growing demand, supportive government policies and increasing awareness of sustainable practices.
#2–Yes, the growth model is deeply problematic. However, while that’s a worthy (and complex) topic for discussion, it’s not really responsive to most of the previous couple of posts. But if you’d like to discuss it, I’d be more than glad to open a new ‘chapter.’
Don Williamssays
1) Please clarify your “counterfactual” – since it seems to be contrary to the facts and to the academic discipline called “arithmetic”.
2) If you track back to the original primary source for SA’s cite, it says that the GLOBAL –NOT just the US – market for electric tractors is only $0.7 bil and is projected to grow to ONLY $3.4 billion by 2030.
Note that the bulk of the 2030 market is projected to be in Europe –not Asia — since electric tractors are currently uncompetitive on price and it takes a rich country to subsidize them. Also, the Green Party does not fare well among hungry people.
A second industry source that I cited projects much lower growth in sales of electric tractors – less than $0.9 billion by 2032.
3) As I noted above, the GLOBAL market for all tractors including fossil fueled ones is almost 100 times larger – $84.5 billion today and projected to reach $114.5 billion by 2029.
4) You also overlook that the market is sales of New tractors. The larger established plant consists of tractors with diesel engines and those tractors can last a decade or more while continuing to emit carbon.
5) Tractors is just one factor in the carbon emitted while feeding 8 billion people. Another factor I noted above is the carbon emitted from production of the massive amounts of synthetic fertilizer needed every year.
The third factor is that the assumption of declining population is contrary both to the growth we see today and the strong financial motivation our wealthy rulers have to push for continued population growth in the major carbon emitting nations.
Don, thank you. I appear to have misread the statistic; it does indeed say “global” market, not US market. My bad! However, while we’re doing arithmetic, let’s go a bit farther with it. The report gives a CAGR of 28% pa. for electric tractors. It’s quite likely that that is going to accelerate, but for an indicative result, let’s just examine what happens if 28% is maintained.
–In 10 years, the electric tractor market will hit 11x, or about $8.3 billion. That’s about 10% of the 2024 total tractor market. Is that “paltry” still? I suppose reasonable people might differ on that.
–However, in 20 years, it reaches $96.9 billion, which is more than 100% of the 2024 total market. Definitely not “paltry!” For context, let’s assume what is almost surely another contrafactual, which is that the overall market maintains its current ~5% growth over the same time frame. At that rate, the $84 billion 2024 becomes a $222 billion market, and the electrics would have 43.6% of the market, which I don’t think anyone would call “paltry.”
–25 years on, it’s $334.5 for the electrics, and just $284.5 for the overall market. Game over for ICE tractors, then, some time 20-25 years from now. Which would give zero emissions from tractors, at least, roughly in time for 2050.
You also said:
Note that the bulk of the 2030 market is projected to be in Europe –not Asia — since electric tractors are currently uncompetitive on price and it takes a rich country to subsidize them. Also, the Green Party does not fare well among hungry people.
No, as I read the report, the bulk of the 2030 market is projected to be in Europe because the bulk of the present market is in Europe. The fastest-growing market appears to be in Asia–at least by eyeballing the graph.
I think you misunderstand the current reality, which is that adoption of EV tech is increasingly being driven by economic, not policy factors (though of course, the two interact.) EVs are now cheaper on a lifetime ownership basis in the US, with cheaper upfront costs coming soon. Tractors may be a bit slower, but I have to believe that the growth we’re seeing in the US doesn’t reflect altogether “uncompetitive” economics.
Finally, I’d note that the epicenter of EV innovation today is clearly in China.
I smell several Straw Man. Did anyone claim 10 million can be fed by conventional chem ag? Did anyone claim it was good idea and a goal to have? Did anyone claim because of that population just isn’t an issue?
Not that I am aware of, but I don’t read all the comments here and only post occasionally.
I don’t know if these STrw Men are directed at me, but just in case, here’s what I know to be true:
1. Even with conventional, we currently feed 8 billion with 30% being wasted. Clearly, if we did not waste 30%, we could feed that many more people, @ 11.4 billion. However. that would be REALLY EFFING STUPID to do given uch ag practices are destroying our ecosystem.
2. So, when *I* say we can feed 11 or 12 billion I am saying, ALWAYS, so tuck this away in your Straw Man’s little head, we can do that with REGENERATIVE agriculture. See the link last month about a new study stating the benefits of regenerative ag, including yield equal to or better than conventional. This is all the more true when we include that regenerative food has a significantly higher nutritional value. So, no, feeding the world and a few billion more is not a real challenge if we remove the politics and economics that keep people hungry. Physically, easily done.
4. HOWEVER, even in a regenerative system it would be REALLY STUPID to want 10 – 12 billion people on the planet because food is not the only need. Those billions of people consume thousands of other things that also damage the environment. That consumption is very far into overshooting the planet’s systems. We must reduce population significantly if we hope to restabilize the ecosystem long-term AND have a lifestyle that allows some of the creature comforts we have now in the wealthier nations.
5. That said, population demographics move too slowly to have a meaningful impact on climate change and ecosystem destruction, et al. Therefore, population reduction as a primary response to mitigating Climate Change is a poor prioritization of resources and policy-making. (I said this previously, so if your Straw Men were referring in any way to my comments, you must have missed this point.)
6. This does not mean population does not matter. As I said above, we need to reduce population, but it does mean it’s one of the longer-term strategies. However, the demographics are already going that way *without* any explicit policies to move it in that direction in many countries. It is, therefore a moot issue until or unless demographics reverse. Further, the simplest, most effective way to reduce population is to educate girls and women and to give them control of reproduction. So… we really do not need any policies on reduction, per se; equality for women does the job.
7. In the short term, reducing per capita consumption is the low-hanging fruit of solutions. That would be incredibly simple to do. Just stop consuming anything we don’t *need* to consume. Note I did not say *easy.* You have to change the very system across the board to really make it work. But, in the short term, a global response, i.e. most countries agreeing to within their own nations, akin to the sorts of programs the U.S. implemented during WWII would get us…. maybe… 40% of the way there? That might buy us time to go truly regenerative.
Regardless, if we don’t reduce consumption @ 80 long-term, I don’t think society remains anything like stable by 2050. A recent paper found 2050 is the midpoint date for the AMOC shutting down, e.g.
Since all those Straw Men are dead, maybe you can enjoy a pot of Straw Man soup!
Cheers
Don Williamssays
Some more facts: UN projects world population to hit 10 billion around 2060 — and I think they are optimistic although they acknowledge uncertainty and that it could possibly hit 11.5 billion by 2100 instead of leveling out around 10 billion.
Africa’s population continues to have a very high growth rate.
I don’t think you actually read the article or considered who the author is.
False-flag/concern-trolling is increasingly popular these days from the usual suspects.
Don Williamssays
The NY Times article was just one article expressing concern over America’s low birth rate.
I don’t think you actually read the Aug 8 post above where I also cited an article in The Atlantic on the subject of a low birth rate. Are you arguing that both the NY Times and The Atlantic are “the usual suspects”?
Without continual growth how will the stock market keep rising, the Rich keep receiving interest on $35 Trillion in federal debt , Social Security/Medicare provided to the elderly and our Cold War 2.0 nuclear arms race funded? By increased taxes on the Rich?
The Rich run America — not philosopher kings who have to beg for research grants every so often. I think population needs to decline but I am merely pointing out the powerful forces of capitalism that will oppose that. Who do you think OWNS The Atlantic?
zebrasays
Don Williams
Don, I was responding to your “and now on the left” phrase… I had read the article you described that way previously, and it was obvious to me that it fit into the category I described of false-flag/concern trolling. It was not a “progressive” expressing concern about declining population; it was just promoting the usual Republican talking points about population.
Read it again more carefully and you will see what I mean.
Ray Ladburysays
It is an understatement to say that the situation with respect to population–be it national, global or local–is complex.
Certainly, Earth is now supporting far more humans than it can sustain long term. That excess population is being maintained by massive use of fossil-fuel based fertilizers and pumping water from finite and fragile aquifers. That cannot continue indefinitely and is already irreparably damaging the planet’s long-term carrying capacity–that is, the planet will support far fewer people than it would now.
That said, there is an instability with respect to human demographics–without population growth in a society, you will have fewer productive individuals to support the young and the elderly. This is a situation that only gets worse as people live longer, even if that increased longevity is also accompanied by increased years of productivity, as it is never a one-for-one relation. This is a situation that could be remedied with increased used of improved robotics–although that comes with increased energy consumption and potential instability in labor and employment.
And that brings us to the political and economic. None of the economic systems we have today are stable in an era of decreasing human population. We’ve seen what happens to the Chinese system when population growth slows. Imagine how it would respond to an actual decrease. Capitalism is probably especially vulnerable to instability if population is not growing, as a growing economy will tend to ossify the income/wealth inequality to which the system is susceptible. Long term, that is bound to cause political instability, as people lose hope that their national dream is anything but a fiction for the majority. To some extent, a lower-than replacement birth rate in a country can be tolerated if the country has a liberal immigration policy. Immigrants bring an influx of ready labor as well as cultural variety that leads to a more interesting culture.
Of course, we’ve seen in the US and Europe how white nationalists respond to increased immigration. It is the reason why the likes of Elon and J. D. Vance advocate for larger families and dismiss the ecological threat of rising global population.
And of course there is the historical fact that the few times when global population has actually shrunk have not been fun. It has taken war, plague and famine to do the job, and even then it was not stable and proved only a temporary glitch.
So, we have a situation where we see how things have to change, but there is no idea for how to get there.
zebrasays
Ray Ladbury,
Ray, the population discussion requires some better focus and clarity about parameters.
First, are we talking about a single Nation-State or the global population?
I’ve pointed out that if the global population declines, the paradigm changes. I’m not sure what people don’t understand abut the resultant economic system… labor becomes more valuable, and resources become less valuable. How does this mean a better life is “a fiction” for the majority of the population? I would think rather the opposite.
Sorting out the consequences for individual countries when global numbers are increasing or held constant is obviously more complicated. Japan is very different from Russia and USA is different from both. The problem is that people try to produce generalized principles from those cases, which just doesn’t work.
As for “getting there”, we have plenty of evidence of what works… without war and disease and famine. Otherwise, we wouldn’t be having this discussion about low fertility rates, right? The only question is how rapidly we can achieve the result.
Mal Adaptedsays
Ray:
We’ve seen what happens to the Chinese system when population growth slows. Imagine how it would respond to an actual decrease.
No need to imagine, FWIW. China’s population has actually decreased in each of the last two years. By my count, the populations of 37 countries have begun shrinking. Many of them are former Soviet Bloc nations. Island nations are also well-represented among the shrinking ones. A number of already-shrinking countries, especially in both Eastern and Western Europe, are undergoing negative economic growth as well.
The next step would be to plot nations of the world with population growth on one axis and economic growth on the other. I couldn’t find a peer-reviewed scatter plot in a few minutes on Google Scholar, but I found some in the “gray literature“. What I found in the peer-reviewed literature was wide agreement that population decline is not strongly correlated with economic decline, as in this Nature article from last year. What will happen to global GDP when global population growth is negative, is far from clear IMO. Interesting times!
Mal Adaptedsays
Me: population decline is not strongly correlated with economic decline (screw blockquoting + bolding).
Actually, looking at the 62-yr trace of GDP in countries where it’s declining currently, it’s evident to the Mark I eyeball that there’s no correlation between population growth and economic growth in those countries. My own eyeballs glazed over at this point.
zebrasays
Mal,
The reference to the Nature article was good but I’m not sure GDP is a meaningful metric for this. Repeating what I said to Ray:
“If the global population is decreased significantly, and held constant, labor becomes more valuable and resources become less valuable.”
That means, in simple terms, you get paid more, and you can own more “land”. What’s the problem?
It’s true that many existing sectors of the economy will become unnecessary. But that’s hardly a problem, since there is plenty of other work to employ the reduced population. The market will decide which activities are worthwhile.
I honestly don’t get it. Is the fear that people will be too happy, and there will not be progress in science or the arts? I doubt it; there are always going to be us curious monkeys in the crowd, who will not be satisfied with the status quo. But, you can’t measure that stuff with this meaningless abstraction of “GDP”.
Susan Andersonsays
JD Vance and Elon Musk are nutters about treating women as birth machines. Elon thinks his ‘seed’ is special, and is beyond weird on the subject. There are others, but they only want white and/or Republican babies, and they’re not interested in helping those babies survive (or their mothers, after all, pregnancy is a serious health condition, which men would know if they got pregnant). Since the NYTimes is a public news outlet, it publishes opinion from all points of the compass, and this birth panic is right wing. Your link is particularly dumb, since it ignores/dismisses climate change and other toxic problems from overconsumption and ‘advises’ people from a position of ignorance. Your title mentions progressives but they are not represented in the article except as targets for unwanted advice.
Piotrsays
Killian: “we currently feed 8 billion with 30% being wasted. Clearly, if we did not waste 30%, we could feed that many more people, @ 11.4 billion”
If it were so easy to do – why we haven’t done it before? Do the food producers and sellers LIKE seeing MOST of their profits wasted? (if their profit margin was, say, 10%, then if they could sell 30% more, without any increase in constant costs, then new profit margin is 4 TIMES higher). Or do the consumers LIKE paying 30% more for food than they need to?
Killian: “ population demographics move too slowly to have a meaningful impact on climate change”
Spoken like somebody who does not understand the consequences of exponential growth and big numbers. Human population between 1960 and 1987 increased from 3 to 5 bln (66%). With more people and more affluence per capita – the emissions of CO2 increased from 9.4 to 21.3 Gt. (225%). In comparison – how much time implementing of your regenerative agriculture, on the scale large enough to reduce GHG emissions from 225% to 100%, would take? Substantially less than 27 years?
Sure, the current % growth is much less than it used to be, but because there are so many of us – we are already about 50% above Earth carrying capacity – the longer we stay above it, the bigger the PERMANENT damage to non-renewable and previously-renewable resources – and the lower FUTURE carrying capacity of Earth for humans.
So I don’t subscribe to your dismissal of the reductions of human population as “too slow to have a meaningful impact“, particularly that distributing free contraceptives and promoting family planning can be done much quicker then completely reengineering WORLDWIDE agriculture, economy and societal values (replacing consumerism, competition and conflict with simplicity, consideration for others, and harmony.
K.: “ Regardless, if we don’t reduce consumption @ 80 long-term, I don’t think society remains anything like stable by 2050. A recent paper found 2050 is the midpoint date for the AMOC shutting down”
Do I detect a note of … glee (I have been warning you for years, but you never listen)?
K: Since all those Straw Men are dead, maybe you can enjoy a pot of Straw Man soup!
Yes, it’s easy to assume that food waste is pure negligence and that with just a little more attention it can be eliminated. Our household experience is rather that considerable discipline is required, and even during periods when you are mustering that discipline more or less successfully, you don’t get waste down to zero. The thing is, most food is perishable unless it’s processed in some form or fashion. Are you sick, and unable to keep anything down? That bread is going to mold anyway, and that nicely-ripe apple isn’t going to stop ripening while you heal, either.
In short, stuff happens–at the household level, the retail level, the distribution level, and right back up the chain.
Chuck Hughessays
People need to start factoring in crop failure to their rosey projections about population growth. We’re not going to see 10 billion people without mass starvation. We’re consuming our way to oblivion. People are already moving away from coastal areas due to storms, fires and flooding.
I just don’t see us being able to sustain that many people for very long.
Mal Adaptedsays
You’re right about the risks of crop failures, but with luck we won’t see mass casualties worldwide before we cap the warming. By we, I mean all humanity. OTOH, the risks increase with both population size and annual fossil carbon emissions. It’s trivially true that whether we can “sustain that many people for very long” is critically sensitive to “how many, for how long?” We can sustain 8 billion now. Will we decarbonize our economy in time to avert a sharp increase in the global death rate? Can we sustain as many as 12 billion (high projections) until that number begins to decline? Projections of either have the same problem of compounding uncertainty due to diverging scenarios.
Geoff Miellsays
Chuck Hughes: – “People need to start factoring in crop failure to their rosey projections about population growth.”
Also see/hear the YouTube video titled Human Impact, Extinctions, and the Biodiversity Crisis with Corey Bradshaw | TGS 136, published 14 Aug 2024, recorded 25 Jul 2024, duration circa 2 hours. The show notes include:
In this episode, Nate is joined by global ecologist Corey Bradshaw to discuss his recent research on the rapid decline in biodiversity, how population and demographics will change in the coming decades, and what both of these will mean for complex global economies currently reliant on a stable environment.
How might the current rate of species loss result in a domino effect of widespread and severe impacts on the health of the biosphere? What are the key factors driving changes in population growth, and how do these vary across different countries and cultures? Could we stabilize these trends and achieve a sustainable balance between biodiversity and human population through targeted policies and initiatives — and how much time is left to act?
This comment stood out for me (per the transcript):
[00:38:37] Nate Hagens:Let’s talk about insects. I had a a butterfly specialist, Nick Haddad from Michigan State on, and he gave some just horrifying statistics on insects.
[00:38:49]So lay it on us Corey, what is the situation? My understanding is that we’re losing insect biomass one to two percent a year. And does that at some point play into your co extinction thesis? Have you looked at that?
[00:39:05] Corey Bradshaw:Well, yes. And no. The yes part is that from, from an ecological perspective, once the insects go, you’re looking at a bottom up effect.
[00:39:18]So when we’re talking bottom from the trophic perspective, who feeds on whom, that you could precipitate a lot more extinctions quickly. Actually it’s even below that. The plants are probably even more important because many of the, most insects are herbivorous, right? So they’re eating the plants and then things eat those insects and so on and so forth.
“That 50% seems a bit high. Only 32% of American voters are registered Republican. Not all Republicans are MAGA-heads.
Still far too many, of course.”
Well, Tom, at least we know you’re not a MAGA-head, although I presume we’ve all figured that out by now, despite your penchant for picking fights. But seriously: it looks to me like Nigel’s “50%” was his way of saying “about half”. He’s right, as today’s poll results all show Harris has wiped out the lead Trump held as late as last week (LMGTFY: https://www.google.com/search?q=harris+trump+poll&tbs=qdr:w). Bloomberg.com (paywalled) calls it a “dead heat”. I, for one, am taking heart from the news!
And while not all registered Republican voters may be MAGA-heads, any of them who don’t vote for Harris will effectively be voting for Trump nevertheless. That’s a problem only because there are far too many people, indeed about half of the voters, who will vote for him affirmatively, whether or not they’re registered Republicans or call themselves MAGA-heads!
You know how our system works, Tom. Most of our elections are decided on slim margins, easily reversed in the next cycle. What still puzzles me, is how Americans let ourselves be divided so neatly down the middle. It seems comparable to the blue and green factions at the Byzantine chariot races – a marketing strategy that resulted in deadly confrontations (https://www.smithsonianmag.com/history/blue-versus-green-rocking-the-byzantine-empire-113325928)!
Radge Haverssays
“…neatly down the middle…”
Well, wandering off topic, I’d say it could be that political strategists and analysts are all operating at the bleeding edge of their field, sort of like the Olympics where winning can come down to hundredths of a second.
But, to continue the olympic analogy, perhaps Republicans are like the Russians, in that they’re not competitive unless they cheat.
Mal Adaptedsays
Radge:
it could be that political strategists and analysts are all operating at the bleeding edge of their field.
My thoughts are along those lines also. In the case of electing a POTUS, the two serious candidates must adjust their messages with trepidation, helped by teams of experts, to pick up the largest number of voters on one end of their ideological range while losing the fewest on the other end. Lately, however, it seems to come down to “whatever she’s for, I’m against”, with the voters sorting themselves out into roughly equal numbers.
Radge Haverssays
Mal,
“…whatever she’s for, I’m against…”
I agree. I think that’s been brewing for a long time, but IMO things started to break under the strain thanks to the Dubya administration. I doubt there’d be a Trump presidency but for the door opened by Dubya… and probably no Trump as we know him without Roy Cohn– pretty much a straight line from the McCarthy era to Trump… IMO.
Add to that the Internet. Who was it who said, “I never knew how many stupid people there were in the world until I got on the Internet?”
Equal numbers? Maybe. I have a sneaking suspicion that they won’t be looking so equal come election day. But we’ll see… and we definitely don’t want to take it for granted.
Thomas W Fullersays
At this point I’m not thinking about elections, I’m thinking about the make-up of the American adult population. Don’t worry, I’ll be obsessing about the election soon enough. And yes, I do know how ‘our’ system works.
I left America because the atmosphere had grown too toxic for me. However, I don’t for one minute think that half of Americans are infected with the MAGA disease. Maybe a quarter.
It may be a skitch better than that; a good chunk of Trump’s support comes from ‘low-propensity voters.’ And his plan for getting them out seems a bit reminiscent of, say, his efforts to fight Covid:
But it’s still crazy, and deeply unsettling, how much support he and the GOP have, even though literally every ‘theme’ of their coronation–er, convention–was based on a false premise. Denialism isn’t just for evolution, smoking, and climate change any more.
So if you American, please get out and Vote Climate in November!
Jonathan Davidsays
Interesting question. This may be a function of election dynamics and resource and funding allocations by political strategists. In elections where a party has an easy win, there are incentives to minimize efforts in those elections. For example, in the industrial states: Wisconsin, Michigan, Pennsylvania, etc. the Democratic party has long held a clear advantage due to the support of unions, arguably leading them to take these votes for granted. The current Democratic strategy has been to shift efforts instead to Georgia, Arizona and even Texas. The minority party, if seeing an opportunity, will expand efforts in those states which have been neglected by the opposing party. If they choose to do so, it’s not necessary to expend more effort than a sufficient level to achieve a win, additional efforts result in loss of efficiency of resource allocation. Over time this could lead to the near-equilibrium electoral balance we see today.
Mal Adaptedsays
Good insight, The selection of Tim Walz as Harris’s running mate seems mindful of the Upper Midwest, to assure those voters they aren’t overlooked. Exciting times!
Michael Longsays
Politico 101: About 40% of the people in the US will vote Democrat, not matter what. About 40% of the people in the US will vote Republican, not matter what. Doesn’t matter why, they just do.
Which leaves just 20% as independent and. on the fence. And it’s that 20% who decide elections. When you consider that about two-thirds (66%) of the voting-eligible population turned out for the 2020 presidential election, that leaves just about 34 million people to decide the fate of the nation.
And given the electoral college, many of those people are in areas where it doesn’t matter how they vote, as the state swings the way the state swings.
Which puts any national election is the hands of a very, very small group of people.
JCM “ [patrick’s] 0.3K guess could represent (0.3K/1.5K) 20% of human-caused global warming to date. A significant figure”
No. the human changes in the water cycle are not significant compared to the human emissions of GHGs. I have already explained to you before, but since you behave as if this wasn’t said, here is a summary:
1. I have shown that patrick “+0.3K” is major OVERestimation: he calculated it for the maximum theoretical effect: that during the fallow season the evaporation from croplands is ZERO (i.e. “desertland”). Since the real croplands during the fallow season is not as dry as a “desert” – the resulting drop in evaporation is only a fraction of the calculated one, and therefore 0.3K becomes a “ fraction of 0.3K”
2. Furthermore, patricks 0.3K did not account for the human irrigation of the crops. The resulting increased evaporation COUNTERS the reduction of evaporation from croplands during the fallow season, i.e. causes a COOLING – that counters all or part of your fraction of 0.3K warming from p.1.
Your best counter to the 2 points above was to … dismiss the value of the climate modelling as: “ imaginary process mechanisms” with “rules about how things ought to be ” according to their authors. Since I have not done either – it must apply to Lague et al. whose modelling paper your brought up, and to climate models in general.
As for your claim of the significance of the human changes in water cycle to the rate of AGW – your warming by a fraction of a fraction of 0.3K happened over …. MANY THOUSANDS OF YEARS, while the current warming by the GHGs levels happens at the rate of about 0.2C/DECADE. So the RATE of global warming caused by reduction of evaporation from croplands is ca. 3 orders of magnitudes LOWER that the rate of warming from human-emitted GHGs.
Unlike you, I don’t consider something that is 3 ORDERS of MAGNITUDE smaller – “ A significant figure”.
JCM: “ Adding in a 5% loss of soil organics and the missing atmospheric carbon sink increases the ecological destruction to roughly 25% of global warming by including major trace gas effects ”
Don’t you even read your own posts??? Your entire claim to fame is that it is “ mindboggling” that the climate scientists in the world continue ignore, what you, a layman in his free time, has been able to figure out – that the RELATIVE importance of the human changes in the water cycle are “significant” COMPARED TO the effects of human changes in GHGs, say:
“ hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
And now you use the same “outputs of trace gases” to … beef up the importance of the water cycles change over …. the human-caused increase in “trace gasses” ????
Your argument that the rate of global surface temperature changes does not fit the rate in (assumed) anthropogenic changes in terrestrial water cycle is reasonable.
I would be, however, still cautious in drawing a bold conclusion in the sense that human interferences with terrestrial water cycle have a negligible influence on global climate.
1) It appears that Lague 2023 is, if not the very first, at least a quite rare work directly aimed to exploration of this relationship.
2) Climate is not the same as temperature. We can and should ask if
changes in water availability for evaporation can or cannot change terrestrial precipitation patterns.
3) Personally, I have a suspicion that although the direct influence of anthropogenic interferences with terrestrial water cycle on global surface temperature may be small, it may be still well possible that their influence on climate sensitivity towards other anthropogenic “forcings”, such as greenhouse gas emissions and/or atmospheric pollution with aerosols, may be significant.
4) It is my understanding that a similar simulation method as used by Lague 2023 could serve for an estimation if there is any difference in climate sensitivity (e.g. towards a change in atmospheric CO2 concentration) between the “swamp land” and the “desert land”. If you think so, I would like to ask if you would be willing to support a plea to moderators for a comment if a such study could be worth of an effort?
Greetings
Tomáš
Davidsays
Links to a new research article and its supplementary materials on: “anthropogenic amplification of precipitation variability over the last century”
David: I know Tomáš Kalisz’s writings are focused on something different
precisely – these are changes in precipitation as an INDIRECT result of humans warming world with increased GHGs.
But it won’t likely stop Mr. Kalisz from profusely thanking you for the interesting paper and then ignoring your caveat and using this paper as a further support for his and JCM appeals to refocus research interests and the finite financial resources from the mitigating AGW via the most -cost-effective way (reduction of GHGs) to the one least ineffective and already at the unsustainable level, as we are rapidly depleting the ground water.
JCMsays
Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Curiously, simulations under CMIP6 expect an increase in ET driven by an increase in temperature from radiative forcing. Given the existing moisture limitation, an increase in ET must also be associated with an increase in moisture availability on land. Models must therefore project an increase in moisture availability with warming to maintain the stability factor.
Observationally, by various measures, analyses have suggested that much of the earth has been drying in recent decades e.g. “An overall consistent increase of global aridity in 1970–2018” https://link.springer.com/article/10.1007/s11442-023-2091-0
“””This study investigated spatiotemporal variability within global aridity index (AI) values from 1970–2018. The results revealed an overall drying trend (0.0016 yr−1, p<0.01), with humid and semi-humid regions experiencing more significant drying than other regions, including those classified as arid or semi-arid."""
This seems to defy a globally averaged increase in moisture availability, and must therefore limit an increase in ET. Considering an important factor in moisture availability is precipitation, this introduces some circularity as continental moisture recycling contributes a large proportion.
Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change. While it is likely that heavy precipitation events are increasing, these may be balanced by longer periods of dry in annual mean.
In terms of moisture availability, precipitation intensities which exceed catchment infiltration rates will result in a net drying. Catchments operate most effectively with low intensity frequent rainfall along with nice spongy storage properties such as healthy soils, wetlands, and other biosystems. Catchment properties, along with moisture recycling, may impact both moisture availability and the associated precipitation regime.
Damaging catchments reduces their infiltration and moisture storage, and precipitation intensities will more often exceed infiltration. Reduced moisture availability in space and duration reduces moisture recycling and decreases the precipitation frequency. This feeds-back into warmer temperatures, more precipitable water, and a higher intensity of rainfall upon oceanic moisture import on large scale frontal systems. Counterintuitively, flood and drought are flipsides of the same coin, as too much water all at once is ineffective for recharge.
Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Unfortunately, only three CMIP6 ESMs out of about 30 include irrigation, and all three assume unlimited water availability for this purpose. Overall a small proportion of foodcrop parcels receive irrigation at some time, focused almost entirely in southern asia. For any given ESM grid cell, the vast majority are 0-5% irrigated. In previous discussions I recommended up to 20% irrigation offset factor during the growing season when converting nature to foodcrop parcel as an upper bound. The effect of moisture availability or absence appears to be practically immediate in ESM. The most abundant foodcrops are generally left to dry (or actively dried) on the field upon maturation – this commences around now in early August in northern-mid latitude.
Given that only 3 ESMs include irrigation, but the CMIP6 overall tends to overestimate an increase in ET over time, this suggests some seriously overlooked factor. Needless to say, including irrigation additionally in all CMIP6 members will result in dramatic overestimates of ET in the ensemble mean. Some compensating factor will need to be recognized, and the most obvious one to me is the profound catchment deterioration and ecological destruction. This annually averaged net desiccation, along with the associated increasing temperature and hydrological extremes, imposes an obvious climate change influence IMO. For globally averaged climate enthusiasts, this may indicate also a diminished climate stability over time simultaneously with radiative forcing.
I will be on holiday in Colorado in the coming days so expect delayed response. cheers
Piotrsays
JCM AUg.6: “Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Except, that we live on a planet that contains oceans, covering 71% of Earth surface, as well lakes, swamps, and rivers, and we live on a planet that has winds – so the water vapour is carried from places where evaporation is unlimited to places where it is limited,
To the extent that Lague et al. state that “the atmosphere has MORE total water vapor in DesertLand than SwampLand simulation. (This seemingly paradoxical result is a consequence of Clausius-Clapeyron law). Which means that the outcome of human irrigation is far from certain – if it helps to increase absolute humidity but without crossing 100% – it would be all warming (absorption of LW by water vapour) and no cooling (by cloud albedo).
More importantly Lague et al put constraints on the effect of evaporation – the MAXIMUM difference in global T (Desertland-Swampland) – around 8K. However, most of the world FAR from being Desertland, and on top of that – irrigation won’t likely convert the deserts all the way into swamps. Consequently, the room for ACTUAL cooling EVEN IF we had UNLIMITED capacity of irrigation – is only a SMALL fraction of that 8K.
But our capacity for further irrigation are the opposite of “unlimited”,
– not only it would require building a mind-boggling amount of new infrastructure to cover the land that could use more water over at least a part of the year,
– but there is not enough water to supply it there.
In fact, the hot dry places that could use extra water MOST, typically don’t have any more water to use left – either because this water is absent (world deserts), or already used it. In fact, in many parts of the world – the future irrigation is likely to decline since we are emptying aquifers often irreversibly (when then pore space in the acquifers, once drained, collapses).
Not mentioning that the more irrigation in warm dry climates – the bigger the soil salinization that harms the very plants we try to help.
Desalination of seawater – is not a solution either – it just can’t produce nowhere near enough of fresh water to cool the global temp. in any meaningful way, and being very energy intensive – its GHG emissions may warm the climate more than the cooling by the extra irrigation.
Hence we don’t have enough water to irrigate to make any dent in the AGW worth of talking.
JCM: Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Not really. I have said that the effect of crop irrigation would further reduce the already small
climatic effect (a fraction of 0.3K warming) caused by reduction of evaporation due to conversion of natural ecosystems to croplands, thus reinforcing my point that reduction of AGW via direct intervention (irrigation) – is probably the least effective^* way of all the ways to mitigate global AGW, and the most limited one – given huge amount of water needed to have any measurable effect and not enough freshwater resources that we have not already tapped.
____
^* “The least effective” is based on the elementary scale analysis: human alterations to evaporation are MINISCULE comparing to the natural fluxes, and the residence time of water vapour is measured in days, not decades like in human perturbation of GHGs.
JCMsays
Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Curiously, simulations under CMIP6 expect an increase in ET driven by an increase in temperature from radiative forcing. Given the existing moisture limitation, an increase in ET must also be associated with an increase in moisture availability on land. Models must therefore project an increase in moisture availability with warming to maintain the stability factor.
Observationally, by various measures, analyses have suggested that much of the earth has been drying in recent decades e.g. “An overall consistent increase of global aridity in 1970–2018” https://doi.org/10.1007/s11442-023-2091-0
“””This study investigated spatiotemporal variability within global aridity index (AI) values from 1970–2018. The results revealed an overall drying trend (0.0016 yr−1, p<0.01), with humid and semi-humid regions experiencing more significant drying than other regions, including those classified as arid or semi-arid."""
This seems to defy a globally averaged increase in moisture availability, and must therefore limit an increase in ET. Considering an important factor in moisture availability is precipitation, this introduces some circularity as continental moisture recycling contributes a large proportion.
Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change. While it is likely that heavy precipitation events are increasing, these may be balanced by longer periods of dry in annual mean.
In terms of moisture availability, precipitation intensities which exceed catchment infiltration rates will result in a net drying. Catchments operate most effectively with low intensity frequent rainfall along with nice spongy storage properties such as healthy soils, wetlands, and other biosystems. Catchment properties, along with moisture recycling, may impact both moisture availability and the associated precipitation regime.
Damaging catchments reduces their infiltration and moisture storage, and precipitation intensities will more often exceed infiltration. Reduced moisture availability in space and duration reduces moisture recycling and decreases the precipitation frequency. This feeds-back into warmer temperatures, more precipitable water, and a higher intensity of rainfall upon oceanic moisture import on large scale frontal systems. Counterintuitively, flood and drought are flipsides of the same coin, as too much water all at once is ineffective for recharge.
Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Unfortunately, only three CMIP6 ESMs out of about 30 include irrigation, and all three assume unlimited water availability for this purpose. Overall a small proportion of foodcrop parcels receive irrigation at some time, focused almost entirely in southern asia. For any given ESM grid cell, the vast majority are 0-5% irrigated. In previous discussions I recommended up to 20% irrigation offset factor during the growing season when converting nature to foodcrop parcel as an upper bound. The effect of moisture availability or absence appears to be practically immediate in ESM. The most abundant foodcrops are generally left to dry (or actively dried) on the field upon maturation – this commences around now in early August in northern-mid latitude.
Given that only 3 ESMs include irrigation, but the CMIP6 overall tends to overestimate an increase in ET over time, this suggests some seriously overlooked factor. Needless to say, including irrigation additionally in all CMIP6 members will result in dramatic overestimates of ET in the ensemble mean. Some compensating factor will need to be recognized, and the most obvious one to me is the profound catchment deterioration and ecological destruction. This annually averaged net desiccation, along with the associated increasing temperature and hydrological extremes, imposes a climate change influence IMO. For globally averaged climate enthusiasts, this may indicate also a diminished climate stability over time simultaneously with radiative forcing.
I will be on holiday in Colorado in the coming days so expect delayed response. cheers
“Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change.”
acted as an incentive for me to repeat my question that I asked
“It is my understanding that a similar simulation method as used by Lague 2023 could serve for an estimation if there is any difference in climate sensitivity (e.g. towards a change in atmospheric CO2 concentration) between the “swamp land” and the “desert land”. If you think so, I would like to ask if you would be willing to support a plea to moderators for a comment if a such study could be worth of an effort?”
Please note that in the graph of annual precipitation from land-based stations
it appears that the variability in annual terrestrial precipitation since ca 1950 may be higher than in previous ca 50 years.
I am not qualified for a statistical evaluation if there is indeed a such difference, and would like to ask if someone could confirm or disprove it. Again, similarly as in case of my question regarding the relationship between water availability for evaporation from land and climate sensitivity towards other forcings (like changes in insolation, greenhouse gas atmospheric concentration and/or atmospheric aerosol pollution), I suppose that it is a question that might be best replied by climate science professionals and that it may deserve their attention,
because it appears that there may be still a knowledge gap in this direction.
If so, would you be willing to support a plea to moderators for a comment?
Best regards
Tomáš
Davidsays
Tomáš wrote: “it appears that the variability in annual terrestrial precipitation since ca 1950 may be higher than in previous ca 50 years. I am not qualified for a statistical evaluation if there is indeed a such difference, and would like to ask if someone could confirm or disprove it.”
.
And then wrote: “Again, similarly as in case of my question regarding the relationship between water availability for evaporation from land and climate sensitivity towards other forcings (like changes in insolation, greenhouse gas atmospheric concentration and/or atmospheric aerosol pollution), I suppose that it is a question that might be best replied by climate science professionals and that it may deserve their attention, because it appears that there may be still a knowledge gap in this direction. If so, would you be willing to support a plea to moderators for a comment?”
.
I’m curious how you reasonably expect a simple reply here in the comments could “confirm or disprove” the matter to your satisfaction? Based on your responses to the various efforts of other commentators who are far smarter than I to address your questions over the past months and months, I’d predict any succinct response would be insufficient.
Tomáš, if your question of swamp/desert land evaporation and mankind’s impact on said lands and the resulting impacts to temperature and precipitation amounts/patterns verses the impact of mankind’s introduction of GHG’s into the atmosphere is really that important for you to understand, than have you considered participating directly in an effort to analyze your question via your own research project?
Just my “layman” opinion.
Piotrsays
T. Kalisz Aug.9 to repeat my question that I asked
I don’t see my answer to that question, so I’ll write it again:
TK: 1) It appears that Lague 2023 is, if not the very first, at least a quite rare work directly aimed to exploration of this relationship.
So what? Do you have a proof that its findings are NOT credible? After all – it was brought up and extensively quoted by JCM, and used by him and you as SUPPORTING your claims about the importance of human alteration of water cycle to AGW. It seems that it …. STOPPED to be credible:
– JCM: “imaginary process mechanisms [following ] rules about how things ought to be [according to their authors”
– you – that it is just one study
ONLY AFTER patrick and I have used the numbers from Lague to show that you both MISREPRESENTED the paper, as supporting your claims.
TK: “ 2) Climate is not the same as temperature.
Tell this to JCM and yourself – since both of you have used the TEMPERATURE results of the Lague’s, as the measure of the importance of the water cycle compared to the GHGs effects on temperature. Therefore, “ Climate is not the same as temperature” is a cop-out after not being able to sustain your argument.
TK: “ 3) Personally, I have a suspicion
Your “beliefs” and “suspicions” are IRRELEVANT until you support them with a defensible argument.
TK: “ 4) “would you be willing to support a plea to moderators for a comment if [a followup study using Lague’s approach] could be worth of an effort?”
No I wouldn’t. Lague’s model have only to put some numbers to illustrate what anybody knowing anything the water cycle already knew from the elementary scale analysis:
Humans do NOT have any appreciable effect on the global T via direct increasing or decreasing evaporation BECAUSE of the MASSIVE VOLUME of the natural water fluxes, and extremely short residence time in the atmosphere (several DAYS). Contrast that with humans GHG emissions which are much bigger % of the natural ones, and the perturbation time of GHGs is measured in at least DECADES, instead of DAYS as in the case of water vapour.
Therefore, you could have a 1,000 studies using Lague’s framework and STILL get the same answer – HUMAN direct modifications of evaporation are just too small to have any significant effect on the Global T. I.e. the conclusions OPPOSITE to your and JCM claims, best summarized by JCM in his recent rant in which he blamed desertification and other ecological calamities on …. considering the AGW being primarily driven by the changes in GHGs, I quote:
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases ”
(c) JCM
The fact that both of you REFUSE to acknowledge the conclusions drawn from not only from your own source but also from a basic scale analysis of relative effects the human perturbation of the water cycle vs that of GHGs – means that:
– either you are unable to accept the quantitative falsifiable arguments that go against your a priori “beliefs” and “suspicions”
– or that you know that it is false, but still follow the old denier’s trope: “Anything but GHGs”, thus diluting the urgency of the global reductions in GHGs, and/or suggesting that the research effort and limited resources should be shifted away from the most cost-effective way to mitigate AGW (via GHG reductions ) to the least effective one (direct changes evaporation).
And in doing so – being “useful idiots” of fossil fuel oligarchy, and tyrannies the depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad:
by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.
So no – I won’t join you in THAT.
Radge Haverssays
TK,
…because it appears that there may be still a knowledge gap in this direction.
If so, would you be willing to support a plea to moderators for a comment?
The moderators read the comments and periodically respond to ideas that are at least interesting if not important. Perhaps you should take a hint from their silence on the matter.
As regards my open question if the perceived increase in terrestrial annual precipitation variability from the NOAA data can be significant or insignificant, I think that an ideal reply would have been a reference to a scientific article analyzing this data.
As regards my open question if there still may be a knowledge gap regarding the relationship between water availability for evaporation on one hand and climate sensitivity towards other forcings on the other hand, I would appreciate any comment from climate science professionals. In case that this knowledge gap does indeed exist, the answer “yes” will be sufficient. If my suspicion in this direction is in fact false, I would of course appreciate a more detailed answer, e.g. a few references to articles dealing with this topics. Or, ideally, a popular review article on this topics by one of the hosts of this website.
As regards your question why I do not resolve my question(s) myself by my own research, I must reply that as a chemist, I do not have the necessary training for climate modeling. And, more importantly, I am afraid that doing any research of this kind is in fact beyond my capabilities.
You may be correct – and you may not be correct. I do not know.
I would much more than mere silence prefer at least a short comment, like “You are wrong, there is no knowledge gap that you assume. Exemplary publicatioons about the relationship between water availability for evaporation and climate sensitivity towards other forcings are A, B, C, D (citations)”.
Or, aternatively: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings,”
Or: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings,”
Or, aternatively: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings, Why do you think that this topics could be of any importance?”
This might prevent lot of noise on this discussion forum, I think. To be honest, lot of contributions published herein raised my doubts if this discussion is really “moderated”.
Greetings
Tomáš
Radge Haverssays
TK,
Again, the name of this thread is “Unforced Variations.” It’s a space to help keep distracting comments out of the comment sections for posted articles. Not long ago RealClimate was about to shut down comments altogether, because they didn’t like what they were hearing and relatively few of the visitors to the site read the comments anyway. So it’s become free form.
Now if you haven’t noticed, the moderators do occasionally respond to comments and requests– like Zebra asking that the comment roll be lengthened. Maybe they simply don’t respond to being bated or to ankle biting or are too busy to give a definitive answer to a relatively minor question, but for whatever reason your request is being ignored.
Doing the same thing over and over and expecting different results is insanity — which now that I think of it, is sort of like trying to talk sense to you.
I tried to structure my orevious post into four points for a better readability, however, there was basically a single idea:
There may be many reasons why construing Lague 2023 the way you do it (that human interferences with terrestrial water cycle have no substantial influence on global climate) may be a too bold and potentially misleading generalization.
Please try to be a little bit more generous and read the phrases like my “suspicion” just as questions, e.g.: Can we, based on the present knowledge, exclude this or that?
I think that asking such questions is not a sin or a crime, oppositely – I believe it may reveal existing knowledge gaps. Should a knowledge gap exist, I think that the better way how to deal therewith may consist in directing scientific research thereto.
If Lague 2023 is indeed a single work that tried to clarify the relationship between terrestrial water availability and global temperature, and if this work is still completely silent about the relationship between terrestrial water availability and climate sensitivity, then I think that my suspicion that (read: my question if) there may still exist a significant knowledge gap may be indeed relevant.
I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes, their hybrid wars against democratic states and/or fossil fuel business.
I believe that if you see the situation I tried to describe (that there might be still a knowledge gap, at least with respect to the relationship between terrestrial water availability and climate sensitivity) similarly, no harm would have arose for your efforts and/or for your integrity if you joined my plea for a such comment.
Greetings
Tomáš
Piotrsays
Tomas Kalisz: “I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes”
On its own – not; in the context of your and JCM activity on this forum – it is:
Your never accepting answers that don’t fit your deniers narrative (“Anything but GHGs”) , your cherry-picking only those parts of answers that you can misrepresent as supporting your claims, and your incessant sealioning (“ a type of trolling [by] pursuing people with relentless requests for evidence, often tangential or previously addressed, while maintaining a pretense of civility and sincerity (“Thank you for your reply.”). It has been likened to a denial-of-service attack targeted at human beings – are all characteristics of a troll..
And since you. Tomas Kalisz, have been trying for more than a year to seed doubt in climate science, and distract the attention from the urgency of the reduction of GHGs – you are either a paid troll, or “ a useful idiot of fossil fuel oligarchy, and tyrannies that depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad: by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.“..
By their fruits, not their protestations, you shall know them. Particularly that the lady doth protest too much.
Whereas climate science is carried out by climate scientists, its public picture is being shaped by both the climate scientists themselves as well as by various educators and media. Therefore, I think that the climate scinece in its entirety can (but does not nessarily need to) differ from its public picture.
I assume that the prevailing public picture of climate science is shaped by IPCC reports. It is in my opinion quite good in presentation of the present level of knowledge. What I consider as its weakness is presentation of existing knowledge gaps, which is in my opinion quite poor.
I mentioned the idea of a Czech philosopher Jak Kršňák that nevědění (which I understand as “awareness of a lack of a specific knowledge”) is equally important as knowledge (vědění) itself.
It is my personal experience that decision making based primarily on available knowledge is very often heavily biased, because existing knowledge is in most cases insufficient. Awareness of existing knowledge gaps and considering risks that a crucial knowledge can be still missing is often helpful and may prevent wrong decisions. For an analogy: Good drivers are aware of dead angles in their view from the car.
The goal of my questions is to find out how much are climate scientists aware of dead angles in their present view on Earth climate. I admit that my questions may sometimes cast doubts about the prevailing public picture of climate science. It appears that the key aspect in which we differ from each other is ithe question if in our view on such doubts.
Personally, I am more confident in persons and institutions who know and are able to admit their knowledge gaps than in those who do/are not. It is my feeling that the revailing public picture presenting the climate scince as “fully settled” is potentially dangerous.
I think that at least on a few details discussed herein, I have already seen the complexity of the studied problem. I can therefore hardly believe that the available projections are fully reliable. If they are not fully reliable, we have to consider also the risk that proposed measures based on these projections may fail. Unfortunately, I miss this approach in present public discourse. Rather, I have often a feeling that we believe that there are no dead angles in our view on Earth climate at all, and that there is no need to ask questions and/or consider alternatives and fallback solutions, because everything is clear.
I would like to find out if the climate scientists themselves really see their existing knowledge so satisfying that they share your view that a question from the public if there still may or may not be an unexplored niche in a specific direction should be dismissed as an effort to undermine and discredit everything what their science reached so far.
Greetings
Tomáš
JCMsays
Your contempt is noted, but it is misplaced given our shared professional and personal interests in climate stabilization.
There’s no use in talking past each other, inventing quantities, and reducing ourselves to scoring cheap debate points. I understand clearly that you believe, using your imagination, that a foodcrop parcel has no influence and that you have conjured specific quantitative values. Additionally, the pseudologia fantastica of fabricating and subsequently believing that I am an agent for GHE denial has resulted in significant barriers to communication. This I know for certain. It is obvious your goal is to advocate for trace gas emission cuts by minimizing the complications of landscape aspects to extraordinary extremes. I understand you are passionate in your beliefs, but it seems to me you are performing for an imagined audience rather than engaging with me substantively.
Moving on, as discussed elsewhere, themes in the IPCC-related documents that frame desertification in terms of trace gas GHG emission versus surface albedo are very likely misleading. In my experience and opinion, it’s damaging and incredible that the community would summarize for policymakers that totally destroying vast acreages at the scale of continents has no net consequence on climate observables—allegedly because the surface albedo compensates for the trace GHG effects almost exactly. It should be obvious, and not a stretch of the imagination, that something significant is missing in that idea. There is no use in conceptually minimizing the billions of hectares of landscape disturbance during our lifetimes. No use at all.
From first principles in traditional teaching, landscapes are central to all things in culture and life. It’s really quite simple to understand that the disappearance of the vast majority of functional ecologies will present as Earth System change. Refusal to acknowledge this wisdom is misplaced. Spiritually, these teachings draw parallels between a lack of respect for land and a lack of respect for humanity as well.
The terrestrial destruction curve resembles a hockey stick shape, with the most pronounced deterioration since mid-20th century. The hockey stick aligns with many other Earth system variables. Regarding the 20% + 5% issue, the message is quite simple—profound deterioration of landscapes expressed in moisture, biological and nutrient cycling may have an outsized influence on realclimates (many times) compared to the trace gas effect. Therefore, evaluating landscape-climate interactions in terms of trace gas budgets misses the target, and results in huge undervaluation in policy advice.
Johan Rockström offers a framework through his planetary boundaries setup at Potsdam, promoting an understanding of the interconnected planetary machinery. He lists the big four workhorses as biodiversity, land, freshwater cycling, and nutrient cycling. These intersect intricately with overarching global climate, ocean, and carbon cycles. He promotes improved interdisciplinary engagement and notes how the silos of the various research streams have yet to intersect. However, he seems encouraged that the gaps are closing. He cites specific examples of tipping point elements reached much more easily when planetary boundaries such as biosystems and hydrologies are pushed concurrently with carbon dioxide.
My professional experience is in environmental monitoring, landscape stewardship, conservation, and restoration. This is not a layman’s point of view. Additionally, the modeling community demonstrates that terrestrial ET change in reanalysis does not match at all with what’s in CMIP expectations, and that TOA trends in SW are much more pronounced than expected. This supports the hypothesis that landscape deterioration impacts significantly climate observables. For each new acre of wetland drained, surface sealed, and soil desiccated pushes us deeper into uncharted territory.
It is obvious that the conventional forcing feedback analysis produced by computation in the climate space has much room for improvement. Improvement will be necessary in order for mathematical formulation to close the gap behind the essential wisdom already known since forever.
Piotrsays
JCM Aug 5: Your contempt is noted, but it is misplaced given our shared professional and personal interests in climate stabilization.
Contempt implies unfair and unsupported with arguments dismissal of other people. Sounds like an apt self-description on your part. It does not apply to me since I have critiqued your claims and your logic with falsifiable arguments. What those arguments, and your inability to falsify them speak about you, is for the readers to judge. By their fruits, not their declarations about themselves, we shall know them.
And no, I don’t think that we really share the interest in climate stabilization – you follow an old denier’s narrative – “ Anything but GHGs” – for years(?) you have been trying to pump up the “mindboggling” importance of human changes to the water cycle at the expense of minimizing the importance and the urgency of the reduction in GHGs, which you discredit as “an artificial fixation and overemphasis on the outputs of trace gases”, and held responsible for desertification and catastrophic ecosystem destruction:
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases
So since you attack the MOST -effective method of reducing AGW (reduction in GHGs) in favour the LEAST-effective one ^* of direct increase in evaporation – then objectively, you are working against the stabilization of global temperature.
And you are helping Russia and Saudi Arabia, which regimes and ability to project power abroad would collapse without the world’s willingness to continue buying their oil and gas.
By their fruits we shall know them.
—
^* least effective – given how small human impact is compared to the volume of global water cycle, and how short the residence time of water vapour in the atm is (~ week) – compared to massive perturbation of natural levels of GHGs by humans and the perturbance residence time measured not in several days, but decades.
I beg indulgence here for a c. 900-word essay (with apologies here for formatting irregularities):
Now that we’ve managed to enter the second half of 2024 CE, it might have become time to consider our overweening reliance on electricity for living our contemporary lives.
Insofar as the politics of energy and energy supply, generation, and distribution require more and more political dithering globally and within domestic polities worldwide, citizens who might decide they can no longer rely entirely on political action from the top-down in fact have a practical response to the creeping onset of Technogenic Climate Change.
My simple idea achieves a dual function: while it can help people lessen contributions to the onset of Technogenic Climate Change, it also can help alleviate personal participation in the maturing global dominance of “tech totalitarianism” (the global ubiquity of technology, tech gadgetry, and tech-driven consumer commerce) and help citizens carve out for themselves hours each day unalloyed with the imposed tyrannies and mandates of “mediated existence”.
“Mediated existence” is exactly what the name says: it is a human life divided into sequences of twenty-four hour days, eight of which optimally might be devoted to sleep, eight of which might be devoted to work/career/labor, and the remaining eight to alimentation and digestion, hygiene and personal grooming, tending to domestic and personal responsibilities and obligations, managing desired economic, social, political, physical, and spiritual affairs, and all other minutes and hours devoted to mediated existence by living passively in front of some kind of screen—participating in “life” via some appliance of mediation, “keeping in touch with the world” via some appliance of mediation . . . “living”, that is, one’s few remaining hours each day via some helpful, marketed, and sold (or subscription-supplied) appliance of mediation.
I call my simple proposal “Unplug-8”.
“Unplug-8” consists of the following: apart from c. eight hours of sleep per night (which is still possible without assistance from any mediating appliance) and apart from work or career (which entails obligatory interactions and interfaces with technologies of numerous kinds for various and numerous purposes), the meagre eight hours a day that any citizen has to call his or her own can be lived, whole and entire, without the first contribution of mediating devices and appliances.
In its extreme form, my simple notion means: unplug your mediating devices and appliances for the eight hours a day you might reasonably be permitted to call your own (or: unplug yourself from them). Do not use or consult your mediating devices for a full and entire eight hours a day: instead, live an unmediated life, an unmediated existence, in touch with the palpable reality of your immediate surroundings, your actual domicile (not the virtual one), your actual physical neighborhood (not your virtual neighborhood), in the city or rural setting where you actually dwell, in the actual hours of your actual life.
No doubt, many will shudder. “Detach myself from internet and cable and streaming fare? Rely on my own cognitive and sensory resources?” What fearful, dread, and daunting prospects!
—but be of good cheer: Unplug-8 is not proffered with any dogmatic or ethical imperative, and realism (even in an age of mediated human existence), when invoked, has to concede that few
will feel psychically fit or psychologically ready to undertake such an about-face. Unplug-8 has to be understood as a voluntary (but viable) option. Even if commitment to a full eight hours-a-day unplugged from mediating appliances and devices seems impractical, remember that mediated existence (with its ubiquitous and continuous commercial prodding and cajoling) is neither aesthetically attractive nor spiritually hygienic. At least at first, Unplug-8 can surely be practiced for just a portion of the eight hours out of twenty-four that modern allowances of “free time” permit: if not “Unplug-8”, then “Unplug-6”—if not “Unplug-6”, then “Unplug-4”, “Unplug-2”, or “Unplug-1”.
The facts remain: electronic technology proffered by its inventors, engineers, and marketeers has become so ubiquitous across the face of the entire planet as to begin to take on the aspect of “tech totalitarianism”. The prospects of mediated existence—run according to the schedules and calendars of tech tyrants—have begun turning the entire globe into a planetary, motor-driven treadwheel, in which all of us are acquiring the aspects of panting lab rats, racing in our endless circles, only to die of exhaustion at the very end of all our circular labors.
Unplug-8 is thus a sound response to both the advent of Technogenic Climate Change (less electricity consumption) and to whatever threats we may take to be posed by the rival advent of ubiquitous, global tech tyrannies. While “Unplug-8”, being voluntary, does not entail any ethical or dogmatic imperative of its own, it does give cause for pause and offers breathing room for harried humans who have been taught and trained to jump through the numerous colorful hoops of vacuous consumerism almost wholly for the sake of terrestrial consumer activity alone.
Unplug-8 at any level of adoption can offer small oases in the deserts of time and history for people to catch breath, to encounter ephemeral existence at least briefly without any interventions of mediation, and can permit moments for other reflections and thoughts on how we may want or care to live our short lives on this hurtling globe, no matter the future of tech tyrannies, no matter the extents of oncoming Technogenic Climate Change.
zebrasays
Edward, alternatively, we might consider the lesson of that Buddhist monk in Tokyo… a very noisy location:
When he wanted to sleep, he would close the window.
When he wanted to practice meditation, he would open it.
Hi Ned. A bit too ‘flowery’ for my tastes. I prefer a direct communication style with the KISS principle.
Barton Paul Levensonsays
Sorry for the double post.
glenmsays
There is another paper on the AMOC shutdown/slowdown with estimates. It is an interesting read.
Probability Estimates of a 21st Century AMOC Collapse
Emma J.V. Smolders1*, Ren ́e M. van Westen1 and Henk A. Dijkstra1
Department of Physics, Institute for Marine and Atmospheric research Utrecht, Utrecht University, Princetonplein 5, Utrecht, 3584 CC, the Netherlands
“By August, if we’re still looking at record-breaking temperatures, then we really have moved into uncharted territory,” said climate scientist Gavin Schmidt in April. Well, July 22 was the hottest average global temperature ever recorded — and July 23 promptly broke that brand new record. Here we are in August, and it is not looking promising.
Schmidt is director of NASA’s Goddard Institute for Space Studies. He was choosing his words very carefully when he used the phrase “uncharted territory,” because that is a frightening place to be.
Now, in one sense we have been in uncharted territory for several decades: our greenhouse gas emissions are driving global temperatures higher than anything we have experienced in the past. But at least we thought we had a map of our probable future.
The history of evolution on this planet through the long, looooong stretches of time, however, is a remarkable story. It’s like the earth KNEW that life in the universe was EXCEEDINGLY rare, so when it finally caught and lit it held onto that flame with a white knuckle grip, refusing to let go, protecting it from the winds of extermination even under the greatest of assaults: The hellish start of this rock. A snowball earth. Being repeatedly pummeled by meteors and asteroids. Five huge extinction events, (one wiping out 96% of life!). Through it all life changed and adapted and stubbornly continued.
That is poetic, my friend. Your choice of simile (“It’s like the earth knew”) over metaphor (The earth knew”) is appropriate. The imagery is explicitly teleological, however, which may be seductive to motivated cognition involving a deified Earth that actively wishes life’s continued existence. I know that’s not what you intend. Your comment is a good one IMHO. This is just an atheist’s observation about framing climate change as a political issue. Feel free to wax poetic (I know I do) whenever you think it will help us decarbonize ASAP, but please don’t give anyone a justification for collective inaction!
Geoff Miellsays
On 2 Aug 2024, The Hamilton Spectator published an op-ed by Gwynne Dyer headlined Climate ‘anomaly’ puts us in uncharted territory. The piece included:
“By August, if we’re still looking at record-breaking temperatures, then we really have moved into uncharted territory,” said climate scientist Gavin Schmidt in April. Well, July 22 was the hottest average global temperature ever recorded — and July 23 promptly broke that brand new record. Here we are in August, and it is not looking promising.
Schmidt is director of NASA’s Goddard Institute for Space Studies. He was choosing his words very carefully when he used the phrase “uncharted territory,” because that is a frightening place to be.
Gwynne, a Canadian journalist and writer originally specializing in military coverage, is a long-time observer and chronicler of the climate crisis, and I believe has several books on the topic. (I reviewed one myself quite a few years ago now, but I’ll spare you the link.) I recommend his work.
Secular Animistsays
This is a problem:
“US politics is an outlier bastion of climate denial with nearly one in four members of Congress dismissing the reality of climate change … A total of 123 elected federal representatives – 100 in the House of Representatives and 23 US senators – deny the existence of human-caused climate change, all of them Republicans, according to a recent study of statements made by current members … The report defined climate deniers as those who say that the climate crisis is not real or not primarily caused by humans, or claim that climate science is not settled, that extreme weather is not caused by global warming or that planet-warming pollution is beneficial.”
Thanks for the link, SA. These parts were also interesting:
The research shows that the American public, perhaps uniquely among people in developed countries, is represented disproportionately by climate deniers. Although 23% of the entire US Congress is composed of those who dismiss the climate crisis, polls show the proportion of Americans who share this view is significantly smaller, by as much as half.
…
Though the portion of lawmakers who deny the climate crisis is stunning, it has been steadily declining in recent years. Just five years ago, 150 lawmakers denied the crisis. But many elected officials who don’t deny the crisis still use anti-climate rhetoric and work to thwart greenhouse gas curbing policies.
…
Among ordinary people, Leiserowitz said the views of the relatively small group of people who deny that temperatures are warming, or tie climate science to conspiracy theories involving Al Gore or the United Nations, are often exaggerated both politically and throughout US society.
“This small minority of Americans are really vocal, they are more likely to vote and clearly they are more than adequately represented in the halls of Congress,” he said.
“They are punching above their weight and having an undue influence on the public square, to the extent that most people don’t want to talk about climate change because they think half of the country doesn’t believe in it. There’s a culture of silence – climate has joined sex, religion and politics as the topics not to bring up at the Thanksgiving table.”
We’ll find out whether denialists are punching above their weight this November. As the article notes, five years ago they were punching at or below their own weight. The IRA of 2022 passed with the narrowest of margins. The decline in affirmative denialism, popular and Congressional, is meliorative, at least. Not enough to matter if Republicans win control of either house, however.
Yes, the clear majority is more or less with mainstream science, yet this bogus “debate” continues.
Mal Adaptedsays
The Six Americas political evolution since 2009 is somewhat encouraging for decarbonization advocates (this one, at least). The numbers of disengaged, doubtful or dismissive Americans shrank by 5% of the total, while the percentage of us who are alarmed nearly doubled. I’m really curious about what accounts for those changed minds. The repeatedly record-breaking weather extremes of the past five years or so probably made a difference. The publicity around the IRA, as a relatively benign collective intervention, may have helped some deniers get past the argument from consequences. And we know younger people are more likely to acknowledge the urgency of collective action; maybe deniers are aging out of the voting population. OTOH, we also know carbon capitalists haven’t slackened their disinformation campaign, even while being hectored from unexpected quarters, not only on RC. A self-described “young conservative“, who wants the GOP to drop its long-standing climate-science denial plank, writes:
Liberals often point out that the Republican Party’s ties to the fossil fuel industry have prevented a shift toward climate action, and while it’s true the industry has a history of obstructing climate policy and supporting many Republican elected officials, it’s a bit more complicated than that. Conservative politicians tell me they just don’t want their constituents to have their oil and gas jobs ripped from them. But now that many fossil fuel companies are pursuing climate action faster than the Republican Party, it’s clear there may be a way to keep those jobs while reducing emissions.
While skeptical of what “Conservative politicians” tell him, I’ll concede “it’s a bit more complicated than that.” This kid is non-dogmatic about climate change, but if he doesn’t vote for Harris/Waltz, he’s choosing the greater evil anyway. Still, maybe $trillions in annual profits actually can’t fool all the people all the time.
While Republican supporters recognize that most Republicans support climate change policy, they may be discouraged from expressing their support due to an information environment disproportionately portraying Republicans as opposed to climate change action.
IMO, the maintenance of that deceptive “information environment” reveals the continued, corrupting influence of fossil fuel producers and investors, who seek to thwart collective intervention in their revenue streams. What Is to Be Done? Collective decarbonization doesn’t mean Leninism, for cryin’ out loud! It does mean voting for Democrats in every election, at least until a (presumably young) Republican candidate openly supports collectively taking the profit out of selling fossil carbon.
Radge Haverssays
Mal,
From the paper:
In other words, people may mistakenly believe that fewer people share their opinion than in actuality, which can discourage them from speaking out and acting in accordance with their views5. As a result, pluralistic ignorance on a large scale can hinder public mobilization on climate mitigation policy3.
Interesting. I wonder about that. Supporting policies in theory wouldn’t necessarily equate to making them a priority even if the misperception of how many support those policies were removed. It’s easier to back burner climate if perceptions of more immediate problems loom disproportionately larger.
OTOH, perhaps a tipping point will be reached when people are more afraid of loosing their homes to fire. flood, etc. than they are of Democrats taking power and sucking the life out of their stupid culture wars and authoritarian impulses.
“There are lots of harmful ways to talk about climate and act on it,” said So. “Just because they accept the scientific findings or say they believe in climate change doesn’t mean that they are not still obstructing climate action, or using rhetoric that is antithetical to climate action.”…
…Among ordinary people, Leiserowitz said the views of the relatively small group of people who deny that temperatures are warming, or tie climate science to conspiracy theories involving Al Gore or the United Nations, are often exaggerated both politically and throughout US society.
“This small minority of Americans are really vocal, they are more likely to vote and clearly they are more than adequately represented in the halls of Congress,” he said.
“They are punching above their weight and having an undue influence on the public square, to the extent that most people don’t want to talk about climate change because they think half of the country doesn’t believe in it. There’s a culture of silence – climate has joined sex, religion and politics as the topics not to bring up at the Thanksgiving table.”
Political polarization and the prevalence of “safe” congressional seats, which encourage candidates to hew to more extreme views in order to secure key party primary contests, have helped entrench this imbalance, Leiserowitz said, along with a flood of donations from the fossil fuel industry.
Mal Adaptedsays
Radge:
“perhaps a tipping point will be reached when people are more afraid of loosing their homes to fire. flood, etc. than they are of Democrats taking power and sucking the life out of their stupid culture wars and authoritarian impulses.”
That’s what I’m hoping for. It wouldn’t take very many Republican voters reaching that point to flip the election.
Turns out Greenland definitely melted out at least once during the Pleistocene, apparently around 416k-ish ybp. It’s commonly known – pick up any CO2 chart dating back 3 million years – CO2 was never above 300ppm or so.
And. Greenland. Melted. Out. Now, unless someone knows of some wild event that occurred around that time – a beach party by aliens, an asteroid nobody knows about, the gods being bored and playing with lazers, dragons on holiday – Greenland is done. It’s just a matter of time.
What now becomes the most important question to humanity is how quickly can the ice sheets stabilize after returning to 260 – 280 ppm? IIRC, a paper I read some years ago said they would **begin** to stabilize withing decades. Not very precise. I believe more recent findings indicated the same…?
So, THEN the question is, how quickly are we *willing* to act to cool the planet. I am certain we can be at negative emissions within five years. In theory, back at 300 ppm in as little as 20, but don’t get hung up on that. It’s BOE math in the best possible, absolutely perfect conditions. Still, 300ppm by 2050 or 2070 would be, frankly, easy with global buy-in.
Greenland guaranteed to go, and already going. That means WAIS along with it, no doubt. AMOC tipping between any time now and 2070.
Time? There is none. Anyone ready for a real discussion of regenerative futures, or y’all wanna figure out where to relocate the entire equatorial population and the entire coastal population of the planet all while trying to keep from dying of flood, famine, storms, heat or unrest?
Killian: – “Greenland is done. It’s just a matter of time.”
It depends on how long the atmospheric GHG concentrations stay above Holocene levels.
On 22 August 2022, at the Cryosphere 2022 Symposium at the Harpa Conference Centre Reykjavik, Iceland, glaciologist Professor Jason Box said from time interval 0:15:27:
“And at this level of CO₂, this rough approximation suggests that we’ve committed already to more than 20 metres of sea level rise. So, obviously it would help to remove a hell-of-a-lot of CO₂ from the atmosphere, and I don’t hear that conversation very much, because we’re still adding 35 gigatonnes per year.” https://www.youtube.com/watch?v=iE6QIDJIcUQ
That suggests:
* the Greenland Ice Sheet goes;
* the West Antarctic Ice Sheet goes;
* Himalayan, European, North American, Russian, Scandinavian, South American, etc. glaciers & mountain ice caps go;
* some parts of the East Antarctic Ice Sheet go.
That process will likely take centuries/millennia, but the first metre of sea level rise (SLR) will be catastrophic for many coastal properties/infrastructure around the world. I’d suggest multi-metre SLR is highly likely before 2100.
GM. Something relevant from Science Daily, August 5th 2024: ” Greenland fossil discovery reveals increased risk of sea-level catastrophe……Seeds, twigs, and insect parts found under two miles of ice confirm Greenland’s ice sheet melted in the recent past, the first direct evidence that the center — not just the edges — of the two-mile-deep ice melted away in the recent geological past. The new research indicates that the giant ice sheet is more fragile than scientists had realized until the last few years — and reveals increased risk of sea-level catastrophe in a warmer future…..”
Geoff Miell. I largely agree with your comments on SLR.
The IPCC say SLR of 2 metres is possible this century if warming gets above 2 degrees. This appears to be due to the possibility of a physical destabilisation of ice sheets a process which could last a few centuries. This would obviously be catastrophic for coastal communities and will result in lots of abandoned infrastructure.
There have been periods in the past where SLR has been well over 2 metres per century, such as meltwater pulse 1a. So its not unprecedented. There was more ice back then to melt, but it looks to this non exxpert like we could still trigger something near 2 metres this century and next.
There have also been periods in the past where ice sheets melted by many metres, taking several millenia to melt, at around 0.5M or less per century. I would say the loss of coastal land would be slower than 1-2 M per century, but would ultimately still be huge, and adaptation will have a significant cost.
Geoff Miellsays
nigelj: – “There have also been periods in the past where ice sheets melted by many metres, taking several millenia to melt, at around 0.5M or less per century.”
In the scientific journal Atmos. Chem. Phys., 16, 3761–3812, 2016, there’s a paper by James Hansen et al., titled Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous, which included (on page 3766):
A sea level rise of 5m in a century is about the most extreme in the paleo-record (Fairbanks, 1989; Deschamps et al., 2012), but the assumed 21st century climate forcing is also more rapidly growing than any known natural forcing.
It seems around 5 m of SLR has previously occurred within a timescale of a century according to the paleo-record, and the current climate forcing is more rapidly growing than at any time in the paleo-record, so I’d suggest it’s not unreasonable to expect a similar accelerating multi-metre SLR within this century.
Real-world ice melt will not follow a smooth curve.
The acceleration of the rate of SLR will continue while ever the energy inputs into the Earth System, and more particularly into the cryosphere and oceans, increase.
With a rate of SLR currently at around 5 mm/y in 2024, looking at the next 50 year duration for the following scenarios:
* A 7-year doubling scenario curve exceeds 1 m around 2055 and 2 m around 2061;
* A 10-year doubling scenario curve exceeds 1 m around 2063 and 2 m around 2072;
* A 13-year doubling scenario curve exceeds 1 m around 2070.
I’d suggest lethal humid heat and worsening global food security are likely to be critical factors that will be more pressing for most locations (compared with the consequences of accelerating SLR) within the next few decades.
Geoff Miell,
I have to call you out on your use of the NASA Feb 2022 report to support a +5m 2100 Global SLR projection. Note the table in that report is Table 2.3 not Table 3.2. And that Table 2.3 shows 2100 SLR projections of +0.3m to +2.0m. So not +5m, while that same Feb 2022 NASA report states:-
A GMSL increase of 2.5 m by 2100 is thus viewed as less plausible, and the associated scenario has been removed from this report. Nevertheless, the increased acceleration in the late 21st century and beyond means that the other high-end scenarios provide pathways that potentially reach this threshold in the decades immediately following 2100 (and continue rising).
The idea of there being a doubling-period for SLR driven by polar ice-loss was an interesting idea a decade-back when the evidence of polar ice-loss (GRACE) was showing that such a doubling may have been occurring. Back then, there was still no discussion of the issue of how such a doubling could be sustained with the massive annual melt-rates required to achieve a +5m SLR by 2100 and Hansen et al (2016) which you reference did address that issue. But the exponential ice-loss was looking less evident in GRACE by 2016 and today even more so, with GRACE-FO data showing the average 2002-23 polar ice- loss of 355Gt/yr (= SLR component of +1.0mm/yr) and the recent-years data showing 70% of that ice-loss (80% since GRACE-FO became operational).
I’m pleased to see the Feb 2022 NASA report does present the “when, not if” concept for future SLR but it is rather well buried which, along with the “committed sea level over the next 2000 years” that defines the “if”, is a message requiring a lot more attention (rather than this ‘SLR by 2100’ messaging).
Sabinesays
Rodger incorrectly claimed – “to support a +5m 2100 Global SLR projection. ”
Neither Geoff or his references suggested any projection anything like that. It’s a bad illogical strawman argument. Read what Geoff wrote again much more carefully, and then get back to Logic and the actual Data involved in that comment and refs.
MA Rodger (at 10 Aug 2024 at 5:16 AM): – “I have to call you out on your use of the NASA Feb 2022 report to support a +5m 2100 Global SLR projection.”
It’s interesting that you refer to the NOAA (NOT NASA, although NASA, US EPA, USGS, US Department of Homeland Security, FEMA, US Army Corps of Engineers, Rutgers University & FIU are listed as contributors) Feb 2022 report but completely dismiss the Hansen et al. (2016) paper reference. Is that inconvenient for your narrative perhaps, MA Rodger?
Thank you for highlighting my typo – “Note the table in that report is Table 2.3 not Table 3.2.”
You refer to the NOAA Feb 2022 report statement:
A GMSL increase of 2.5 m by 2100 is thus viewed as less plausible, and the associated scenario has been removed from this report.
It may well be considered “less plausible” by NOAA at this time, but that does not mean it’s IMPOSSIBLE. The paleo-record indicates it has been possible in the past, per my reference to the Hansen et al. (2016) paper. I’d suggest it would be very foolish to ignore history. This suggests to me NOAA is perhaps engaging in “scholarly reticence.”
Professor Jason Box says in the YouTube video from time interval 0:01:50 (bold text my emphasis:
“Now if climate continues warming, which is more than likely, then the loss commitment grows. My best guess, if I had to put out numbers; so by 2050, 40 centimetres above 2000 levels; and then by the year 2100, 150 centimetres, or 1.5 metres above the 2000 level, which is something like four feet. Those numbers follow the dashed-red curve on the IPCC’s 6th Assessment, which represents the upper 5-percentile of the model calculations, because the model calculations don’t deliver ice as quickly as is observed. If you take the last two decades of observations, the models don’t even reproduce that until 40 years from now.” https://www.youtube.com/watch?v=8jpPXcqNXpE
Ice loss observations are well in advance of what most of the modelling suggests.
Per the WMO’s State of the Global Climate 2023, on page 6:
* From Jan 1993 to Dec 2002, the average rate of SLR was 2.13 mm/y;
* From Jan 2003 to Dec 2012, the average rate of SLR was 3.33 mm/y; and
* From Jan 2014 to Dec 2023, the average rate of SLR was 4.77 mm/y. https://wmo.int/publication-series/state-of-global-climate-2023
Thus global mean sea levels since the beginning of year-2000 to the end of year-2023 have risen:
(3 x 2.13 mm) + (10 x 3.33 mm) + (10 x 4.77 mm) = 87.39 mm
For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 156.7 mm (or 244.1 mm SLR relative to the Jan 2000 level)
2050: 383.0 mm (or 470.4 mm SLR relative to the Jan 2000 level)
2060: 835.7 mm (or 923.1 mm SLR relative to the Jan 2000 level)
2070: 1741.0 mm (or 1828.4 mm SLR relative to the Jan 2000 level)
For a 13-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 134.7 mm (or 222.1 mm SLR relative to the Jan 2000 level)
2050: 293.9 mm (or 381.3 mm SLR relative to the Jan 2000 level)
2060: 565.2 mm (or 652.6 mm SLR relative to the Jan 2000 level)
2070: 1027.6 mm (or 1115.0 mm SLR relative to the Jan 2000 level)
Prof Jason Box’s comments referred above suggests to me that the SLR rate doubling time for the period from now to year-2050 is likely somewhere between 10- and 13-years.
Whether the doubling time process continues through to 2100 remains to be seen. I’d suggest it’s heavily dependent on whether we/humanity can rapidly reduce GHG emissions from now on, or not, and begin large-scale atmospheric carbon drawdown.
I’d suggest what looks increasingly likely is that SLR will exceed well over 1 metre relative to year-2000 levels by year-2100. That will be undeniably catastrophic for many coastal properties and infrastructures. Whether SLR reaches 1.5 m or 2.0 m or significantly more by 2100 is academic – societal chaos has already well and truly ensued.
MA Rodger (at 10 Aug 2024 at 5:16 AM): – “But the exponential ice-loss was looking less evident in GRACE by 2016 and today even more so, with GRACE-FO data showing the average 2002-23 polar ice- loss of 355Gt/yr (= SLR component of +1.0mm/yr) and the recent-years data showing 70% of that ice-loss (80% since GRACE-FO became operational).”
Since the 1970s, thermal expansion of the oceans has accounted for roughly half of measured global sea-level rise. The other half is due to land-based ice melt from ice sheets and glaciers. Together, these make up what is known as “eustatic” sea level.
Sabine,
I actually watched your ‘How I Lost Trust in Scientists’ video a few days back, (and more recently your John Clauser debunking).
I think I was a bit disappointed that the ‘How I Lost Trust in Scientists’ message set the climatology of climate change alongside ESP research and the researches of theoretical physics. So initially I worried where your message was going, especially with it giving the view that financial self-interests (mostly) is what drives the ‘physics’ problem. My experience (in other fields of academia) suggest it is otherwise (not financial), more about a researcher’s reluctance to divert off a slippery slope that has lead them somewhere with its bitter blasting of reality nobody explained existed. Indeed, the public message they probably initially heard-given was likely the opposite. As you later say, the situation is “baked into the current system.”
And this led on to your video stating that climate change is worse than a hoax, which was sounding really ultra-controversial.
But this ‘worseness’ you describe as being climatology underestimating the rate of warming and also underestimating the uncertainty. So I see little controversy, that is unless the ‘rate’ and the ‘uncertainty’ are seen as extreme (like 5m SLR by 2100 – “It seems around 5 m of SLR has previously occurred within a timescale of a century … so I’d suggest it’s not unreasonable to expect a similar accelerating multi-metre SLR within this century.”).
And having myself followed the climate change science for a quarter of a century and been bashing on about it for a lot longer, I would say that the “baked into the current system” problem doesn’t really exist within the climatology. The problem was/is how to turn messages like ’emissions must certainly peak before 2020′ and ‘climate change is a planetary experiment we need to stop’ into the political actions to cut emissions.
Geoff Meill,
NOAA not NASA. My bad!!
But you should know by now why I find Hansen et al (2016) problematic, and should know it is not the same as a ‘complete dismissal.’ As I have been saying for many a year, a potential multi-metre SLR by 2100 comes down to ice dynamics. So I do pay attention to the likes of Jason Box as well as GRACE-FO data.
Your stopping your up-thread SLR projections at +1m and +2m falls into the same trap as IPCC projections stopping at 2100. The rate of SLR will keep going at the same rate for a long time after. To prevent this will require cooling the planet down significantly.
Projecting your 10-yr or 13-yr doubling of SLR from your start-conditions gives a 2100 SLR of +15m and +6m respectively. And with a linear rise adopted past 2070, that would be a 2100 SLR of +6m and +4m respectively.
Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward and in my mind a whole different subject. And additionally, whether we reach global averaged SLR of +2m by 2100, 2200 or 2300 makes it all a bit academic.
In the short-term SLR does indeed result from thermal expansion as the biggest contributor (comprising perhaps 39% of 2006-18 SLR obs according to Slangen et al 2022) with non-polar ice also shown a big player (20%) as is land water (16%). That leaves smaller contributions for Greenland (14%) and Antarctica (11%). But the potential for multi-metre SLR rests solely with the polar ice caps. IPCC AR5 WG1 Fig 13.14 shows a thermal expansion contribution of +0.42m/ºC after 2,000 years, non-polar ice fully melting out with a total potential contribution of perhaps +0.5m and presumably we won’t feel the need to pump out so much of the 44M Gt(H2O) estimated in various aquifers globally by Ferguson et al (2023) (thus with a potential +125m SLR if we managed to pump out the lot). IPCC AR5 puts Antarctica with a contribution of +1.2m/ºC and Greenland perhaps +0.5m/ºC with an added 5m when it becomes unstable and melts down.
So, while “ice loss is not the only contributor to SLR,” it is the overwhelming cause of SLR going multi-metre.
Geoff Miellsays
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “But you should know by now why I find Hansen et al (2016) problematic…”
Jealously perhaps?
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “Your stopping your up-thread SLR projections at +1m and +2m falls into the same trap as IPCC projections stopping at 2100.”
Predicting the longer-term future is a fools errand – far too many variables.
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “The rate of SLR will keep going at the same rate for a long time after.”
Will it? It depends on whether we/humanity can rapidly reduce human-induced GHG emissions AND begin large-scale atmospheric carbon drawdown to start returning the Earth System back to Holocene conditions, or not. Per Jason Box, the current GHG levels commit the Earth System to more than 20 m of SLR. As I stated in an earlier comment:
It depends on how long the atmospheric GHG concentrations stay above Holocene levels.
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward…”
According to sea level rise projections, nearly one billion people will be exposed to much greater risks of flooding by mid-century. Is that not “catastrophic” enough for you, MA Rodger? https://earth.org/sea-level-rise-projections/
Here’s an example. The UAE has almost completed a 4-nuclear reactor project at Barakah, on the shores of the Persian Gulf. Per the IAEA’s PRIS database:
The APR-1400 reactors have a design lifetime of 60 years (per WNISR-2023, page 72), with the possibility of a life extension for a further 20 years. That means it’s possible the Barakah Nuclear Power Plant may still be operational beyond 2100 (if civilisation doesn’t collapse before then). https://www.worldnuclearreport.org/-World-Nuclear-Industry-Status-Report-2023-.html
Per Climate Central’s Coastal Risk Screening Tool, the Barakah Nuclear Power Plant site appears to be at risk of inundation beginning from around 1.0 m of SLR. It gets much worse at 2.0 m SLR, with all four reactors at risk. And most of the site is inundated at 3.0 m of SLR. https://coastal.climatecentral.org/
Some examples at 1.0 m SLR:
* the Mekong River delta is inundated;
* the northern end of the 16R/34L runway of Sydney Airport (SYD) is inundated;
* Bangkok City is inundated;
* Amsterdam City is inundated;
* Ho Chi Minh City is inundated;
* Hamburg City is at risk.
I’d suggest 1 m of SLR is more than enough to cause chaos/catastrophe for many coastal and estuary locations around the world. Add periodic storm surges on top of that and more locations are impacted. That’s likely billions of lives disrupted directly or indirectly.
Piotrsays
MA Rodger 12 Aug “But you should know by now why I find Hansen et al (2016) problematic…”
Geoff Miell 13 Aug : “Jealously perhaps?”
Really? That’s what you understood from MAR posts on the subject???
MA Rodger: “Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward and in my mind a whole different subject”
Geoff Miell According to sea level rise projections, nearly one billion people will be exposed to much greater risks of flooding by mid-century. Is that not “catastrophic” enough for you, MA Rodger?
Have you even read MAR’s sentence before you blew your top, Geoff Miell?
And if _that_ is your response to MAR, I shudder to think how would you treat a guy who called the threat of SLR …. “less pressing”.
“ I’d suggest lethal humid heat and worsening global food security are likely to be critical factors that will be more pressing for most locations (compared with the consequences of accelerating SLR) within the next few decades
Geoff Miell, Aug. 8.
Paul Pukite (@whut),
This was explained by ‘our’ Sabine. Due to “a typo”apparently.
Killiansays
Geoff: Yeah, all the points you made were rather clearly made in the OP. There’s no point in discussing stabilizing the ice sheets if it can’t be done… right? And, clearly, if Greenland has melted out, so will everything else be melting. Common knowledge, so no need to specify.
Yes, SLR of at least 1M+ by 2100 is now concensus. I said it over 15 years ago (at least one meter, two likely, 3 possible. Science says 5 is possibe) so… again… no need to specify/repeat the obvious.
I don’t like writing long posts. Eschewing the obvious helps keep them short.
Nigel: You realize that is about the paper I posted… yes? Clear communication would be, “Here’s an articl about the linked paper.”
Secular Animistsays
Killian wrote: “Anyone ready for a real discussion of regenerative futures”
Please consider discussing your ideas about regenerative futures with those who are in a position to actually do something about it. Arguing about your ideas with the half-dozen people who read this blog is unlikely to accomplish anything.
Thank you for your enhancement. My Journal Gazette article fails to provide links or any info on the scientists (no names), with only a reference of the work coming out of a “Swiss climate research institute.” After checking the reference links you provide, I believe you are spot on that it’s Pfister et al (2024) that the Gazette story is about.
So between the above and the work involving Japanese cherry blossoms you reference, I can learn a bit about the science and methods that allow for the development of this type of proxy. Which I will enjoy!
Oh, almost forgot–if the short music video is a viable cultural form for you, or someone you know, you might be interested in checking this one out. It’s ironically titled–Drill, baby, drill!–uses an (involuntary) audio sample from He Who Shall Not Be Named, and, if I may immodestly say so, has received some praise from early listeners.
Copernicus ERA5 has reported for July with a global anomaly of +0.68ºC, a small increase on the June anomaly (+0.67ºC) [& also a tad above both April (+0.67ºC) & May (+0.65ºC)]
As expected July 2024 did come in below the July 2023 anomaly (+0.72ºC) making an end to the run of thirteen “scorchyisimo!!!” hottest ‘This Month’s on record.
Yet we may be in for another “scorchyisimo!!!” month in August. Copernicus ClimatePulse daily data shows the cooling from the ‘bananas’ anomalies of the last third of 2023 (averaging Sept-Dec +0.87ºC) has been taking a bit of a holiday at the moment. And with the early-days of August averaging +0.78ºC, somewhat higher than the anomaly for August 2023 (+0.71ºC), we could be seeing a “scorchyisimo!!!” August 2024 if the rest of this month averages don’t cool below +0.69ºC.
If the cooling doesn’t resume, maybe calling this pause in the cooling-off “a bit of a holiday” is wrong.
(The Uni of Maine Climate Reanalyser, which appears a few days in arrears of ClimatePulse, shows the Southern Hemisphere has been the cause of recent global “scorchyisimo!!!” days although the NH has been ‘holidaying’ itself. For a nerd-eye’s view, see graphics showing global NH & SH ERA5 5-day traces ‘First Posted 15th Dec 2023’)
And even an extended “holiday” could be enough to see the full calendar year of 2024 make ‘Hottest Year on Record’. The data Jan-Jul shows this would require Aug-Dec 2024 to average above +0.46ºC (Previous years have seen Aug-Dec average 2023 +0.84ºC, 2019 +0.43ºC, 2015 +0.38ºC, 2016 & 2020 +0.37ºC, 2021 +0.36ºC.) and less cooling is starting to look a bit more likely as the cooling in NINO3/4 did itself take a bit of a holiday through July, reducing the strength/likelihood of the coming predicted La Niña, this apparently “a notable difference.” And it would be an arriving La Niña that would be bringing the cooling required to head-off a “scorchyisimo!!!” 2024.
Barry E Finchsays
Lazy Summer cut’n’paste about Science Censorship (which an Expert Googleologist pointed out at me on Realclimate is only caused by my linked adverts to Eaton’s catalogue ladies’ lingerie Section, hey I get a stipend). The following might slip past the Ginormous Realclimate Censorship Bureaucracy caught napping in Summer though. https://www.youtube.com/watch?v=oqu5DjzOBF8 @grindupBaker Well, either this video is my Final Refuge for offering high-quality science assertions for others to comment on, refute with good science, or whatever they want, usually verifiable from me by scientific consensus, or else my own accepted physics & logic, or if not my Final Refuge any more then I have no Refuge for disseminating high-quality science because the old reliable “potholer” has “gone bad” on me, Censoring the Living Crap out of my high-quality science and asking me questions to which my accurate replies are Censored never shown to anybody.
From https://www.youtube.com/watch?v=HhAX42dT09w
@grindupBaker Potholer’s statement at 16:40 to 16:44 is factually incorrect. Here’s assessed science. Ice sheets & vegetation changes albedo-change feedback caused most of the warming, an humongous +ve feedback. The proportions of the things that warmed Earth by 7.45 degrees from the last glaciation period (colloquial “ice age”), warming from 17,300 to 6,000 years ago are:
0.5 +- 1 w/m**2 8% Milankovitch cycles orbital eccentricity, axial tilt & precession of the equinoxes changes
forcing (what pulled the trigger that started it)
3.5 +- 1 w/m**2 53% ice sheets & vegetation changes albedo-change feedback
1.8 +- 0.3 w/m**2 27% CO2 change feedback
0.4 +- 0.1 w/m**2 6% CH4 change feedback
0.4 +- 0.1 w/m**2 6% N2O change feedback
:::::::::::::::::::::::::::::::::::::
6.6 +- 1.5 w/m**2 total
As you see the massive ice sheets & vegetation changes albedo-change feedback was 2.0 times as much effect as the CO2 (and there was also CH4 & N2O effect to consider). That 6.6 w/m**2 of total imbalance plus water vapour & cloud feedbacks is what increased Global Mean Surface Temperature (GMST) by 7.45 degrees from the depths of the glaciation period “Ice Age” 17,300 years ago to the Holocene Optimum 6,000 years ago, which is a factor of 7.45 / 6.6 = 1.13 degrees per w/m**2 whereas I got my 0.97 degrees per w/m**2 over 2,000 years above from 25 separate proxies of the massive PALEOSENS project (not just from 1 de-glaciation).
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@Leafsdude Sources, please.
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@jaykanta4326 Nothing you brought was actual science, no matter what you think.
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@grindupBaker @Leafsdude I’m being massively censored as always since 2022 but I’ll put this reply in my notes and maybe try again some place some time. It is at 8:00 at https://www.youtube.com/watch?v=KTTlAAiwgwM Acknowledge this information.
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@potholer54 @grindupBaker — Thanks for taking the time to lay all this out. But really, I’m not the one you should be talking to. I showed the relevant studies in the video, so perhaps you could talk to the authors.
====================================================================================
You will not see my information “Sources” to @Leafsdude because my comment above is Censor-Deleted by GoogleyTubes (as per >70% for my science comments) or “potholer”.
And I am now in the Kafkaesque situation of being advised by random half wits that “Nothing you brought was actual science” because I quoted a “James Hansen” in talk he gave at American Geophysical Union (AGU). Hilarious.
Barry E Finchsays
If anybody has the knowledge please correct my placeholder “1,500” below or point to something definitive that I ‘d get that from with <3 hours effort (Or tear my entire babble into shreds if you're really challenged to fill the hours in the day).
So-called "greenhouse effect" physics: It happens in Earth's troposphere. The H2O gas & CO2 in Earth's atmosphere manufacture ~1,500 times as much radiation as the Sun's radiation that Earth absorbs (or something of that scale, hundreds of times as much). Taking 1 Unit as the Sun's radiation that Earth absorbs (which is 99.93% of all energy going into the ecosphere, geothermal and all the human nuclear fission and fossil carbon burning are 0.035% each) and the 1,500 times as a workable example (not accurate) to describe the physics concept:
==== Atmosphere energy (as power) Budget ====
Units
0.33 Solar SWR that Earth absorbs into the atmosphere
1,500 LWR manufactured by H2O gas & CO2 molecules in Earth's atmosphere, using up 1500 "heat" Units
1,497.65 LWR absorbed by H2O gas & CO2 molecules in Earth's atmosphere, generating 1,497.64 "heat" Units
0.92 LWR Leaks out the top of Earth's atmosphere and goes to space
1.43 LWR Leaks out the bottom of Earth's atmosphere and goes into the surface
1.57 LWR Leaks out the surface and goes into the bottom of Earth's atmosphere
0.45+x "Heat" (regular+water evaporation latent) rises from the surface into the troposphere at a range of altitudes
x "Heat" (regular+water condensation latent) goes from the troposphere at a range of altitudes into the surface
==== Surface energy (as power) Budget ====
Units
0.67 Solar SWR that Earth absorbs into the surface
1.43 LWR Leaks out the bottom of Earth's atmosphere and goes into the surface
1.57 LWR Leaks out the surface and goes into the bottom of Earth's atmosphere
0.45+x "Heat" (regular+water evaporation latent) rises from the surface into the troposphere at a range of altitudes
x "Heat" (regular+water condensation latent) goes from the troposphere at a range of altitudes into the surface
0.08 LWR Leaks out the surface and goes to space
————–
LWR straight from the surface to space is because H2O gas, CO2, CH4, O3, NOx, CFCs don't absorb those wavelengths
Earth makes LWR & SWR photons from the centre of Earth's core to the top of Earth's atmosphere (it's all various atoms & molecules making it) in an amount of several hundred billion of those Units above, an amount of several hundred billion times as much as the Sun's radiation that Earth absorbs. It can't much get out to space though because practically the exact same amount of photons several hundred billion times as much as the Sun's radiation here also gets absorbed by the same, or other, atoms & molecules by the time it's travelled a few microns in solids & liquids, or travelled metres in troposphere gases, or travelled metres to kilometres in stratosphere gases and higher, being converted when it's absorbed into causing faster atom or molecule speed, kinetic energy (which is what's commonly called "heat").
————–
So there's the balance at the top-of-atmosphere (TOA) with 1 Solar SWR Unit being absorbed below and 0.92+0.08=1 LWR Unit being sent through the TOA to space. The "greenhouse effect" is the fact that only 0.92 leaks out the top of Earth's atmosphere but a larger 1.43 leaks out the bottom of Earth's atmosphere into the surface, because only the leakage to space gets rid of the constant stream of solar SWR energy, not the leakage into the surface. If they were both the same, both 1.175, then there'd still be 2.35 leaking out of Earth's atmosphere but there'd be no "greenhouse effect" (as you see, out of the top of Earth's atmosphere to space has gone up from 0.92 to 1.175 so there's obviously much more cooling). The reason why they are unbalanced with more leaking out the bottom than out the top is simply because Earth's troposphere is usually by far (much) colder at the top than at the bottom and colder gases make less radiation than warmer gases because they collide less frequently and with less force (that's what "colder" means, it's just molecules bashing other molecules less frequently and with less force).
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If more H2O gas & CO2 molecules are added into Earth's troposphere then the 0.92 that leaks out the top of Earth's atmosphere is reduced and the 1.43 that leaks out the bottom of Earth's atmosphere is correspondingly increased. For example, add some ghg molecules for a 0.01 Unit effect and the 0.92:1.43 leakage changes to 0.91:1.44 leakage, so there's more "greenhouse effect". That 0.01 Unit example is a "forcing" of 2.4 w/m**2 which is 60 years of the current ghgs increase and is expected would warm by ~2.4 degrees with the feedbacks.
Barton Paul Levensonsays
BEF: So-called “greenhouse effect” physics: It happens in Earth’s troposphere. The H2O gas & CO2 in Earth’s atmosphere manufacture ~1,500 times as much radiation as the Sun’s radiation that Earth absorbs (or something of that scale, hundreds of times as much).
BPL: No, that doesn’t sound right at all. The greenhouse radiation received at Earth’s surface is about 384 watts per square meter, while the solar illumination at the surface is 188 W/m^2. Around twice as much, not 1500 times as much.
Barry E Finchsays
BPL As clearly indicated in my table the “1,500” approximation, placeholder quantity though it be, does not refer to the relatively-minuscule leakage of LWR from bottom (your quantity) nor from top of atmosphere but to the TOTAL photons manufactured in the troposphere. Obviously, the TOTAL photons manufactured would only be of similar quantity to the leakage if the IR gases absorbed hardly any photons, which I don’t think is the case. In fact I clearly suggested for Scale only that something of order 1,000 times as much photons or photon energy gets manufactured as the portion that gets past other molecules (not absorbed) and makes it out of the top or bottom of the air. I thought it was absolutely crystal clear and not subject to any misinterpretation. I’m quite perplexed as to how I’m misphrasing it because it seems so trivially simple to me. Which is to say that it might be correct, what is happening, or incorrect, not what is happening, but either way it seems to me trivially obvious and crystal clear what I’m asserting (Right or Wrong). I’m at a loss.
Like BPL, I found your formulation not so crystal clear. (And by the way, when I was writing my Doctoral dissertation, I had your experience vis a vis my advisor. It was a painful experience, but it did help my prose, as to this day I try to remember to simplify my sentence structure and make references more explicit, to ease the reader’s mental workload.)
But perhaps I’m starting to get it. Let’s see.
Approaching it by way of the old bathtub analogy, insolation and upwelling LWR (etc.) absorbed by the atmosphere correspond to the water coming from the faucet; LWR emitted to space (etc.) correspond to the water going down the drain; and your placeholder “manufactured photons” correspond to the water sloshing around the tub.
Accurate, or mostly accurate?
Barton Paul Levensonsays
I think my 384 W/m^2 figure is too high. Other sources give 333.
patrick o twentysevensays
I thought B.E. Finch’s comment was clear: he’s referring to the total rate at which energy is being emitted as photons, within the whole volume (or mass) of material. It is a flux that is not directional through space …
(photons are generally emitted equally in all directions (absorption cross sections are generally isotropic in the atmosphere – aside from eg. certain ice crystals which drift with preferred orientations – although perhaps if we count all emissions within the ice and not just those which emerge from surfaces… oh, wait, crystals can have anisotropic properties…)
… but a flux through form (from internal energy (of atoms/molecules/electrons/etc.) to radiant energy (photons)).
We could consider this to be the “gross radiant cooling”, where net radiant cooling is that minus the rate of absorption of photon energy. Aside from variations in temperature, and Planck function (Bν) over the spectrum**, Gross radiant cooling per unit mass is proportional to opacity**** – ie, the mass absorption coefficient = k_a ,– ie, contributions from different materials add linearly, each contribution is proportional to the relative concentration of material (***relative to total mass of a volume).
——————— ———————
**,**** – setting aside stimulated emission. stimulated emission ÷ direct absorption = function of temperature … (assuming LTE, or at least LEDNLIE (Local Equilibrium Distribution of Non-Latent Internal Energy, my own acronym))
… (off the top of my head, I think it’s exp[-E/(kT)] ),
both proportional to ambient radiances, so it’s convenient to combine them into a sort of net absorption (proportional to 1 − exp[-E/(kT)] ), which is what absorption cross sections and absorption coefficients account for: the absorption cross section σ_a is the area which would net-absorb the intensity (= radiance * area facing a direction) that a unit of material absorbs.
Spontaneous emission is still accounted separately, as the emitted intensity (= radiance * area facing a direction) filling the opaque σ_a; this is also proportional to exp[-E/(kT)] … and a function of the spectrum, and (n_{r})²= the square of the real component of the index of refraction (for isotropic materials; idk about anisotropic materials …) – fitting this into the area σ_a gives radiance = Bν https://en.wikipedia.org/wiki/Planck%27s_law
(proportional to
exp[-E/(kT)] ÷ ( 1 − exp[-E/(kT)] )
= 1 ÷ ( exp[+E/(kT)] – 1 )
)
(Given Planck function formulas tend to exclude a factor (n_{r})² because n_{r} = 1 is assumed (at least approx.))
… and so the visualization of (for isotropic absorption) incandescently-glowing perfect opaque blackbody spheres (same radius as circle which has area σ_a) representing absorption and emission per unit material, in average effect.
Gross radiant cooling per unit mass by gases is spectrally concentrated in the line peaks, especially of strong absorption lines, etc., and increases with increasing opacity. Net radiant cooling per unit mass, OTOH, tends to peak in magnitude** at intermediate opacities …
(except at temperature discontinuities over optical depth – eg. TOA (net cooling per unit mass is unbounded) – also at discontinuities in slope of Bν over *****normalized optical depth (net cooling per unit mass approaches a nonzero saturation limit))
…, where there is a significant amount of absorption cross-sectional area per unit total mass, but a significant distance over which photons may travel from emission to absorption – ie., the hotter and colder cross sections can still ‘see each other’ and so there can be net fluxes from hotter to warmer masses.
(**- Net radiant cooling may flip sign (and net fluxes through any horizontal area may flip direction), over the course of doublings of opacity, depending on the shape of the temperature profile (in terms of Bν(normalized optical depth as vertical coordinate)), but in the extreme-end values (transparency, quintuple²⁰ pea soup fog), net radiant cooling or warming …
(between and excepting any bounding ‘surfaces’ ie., Space, surface, clouds’ ‘surfaces’ if you count them separately, etc.)
… goes to 0 (with exceptions noted above).)
*****Normalized optical depth (as vertical coordinate) = height in terms of τ (as vertical coordinate), ÷ total τ of whole column of atmosphere. Uniformly doubling τ (optical depth), ie., doubling k_a (which may vary as a function of vertical mass path), keeps normalized optical depth constant.
Column total Gross radiant cooling (for isotropic absorption) (excluding stimulated emission), per unit horizontal area, = ∫ ∫ 4π sr · Bν dτ · dν
——- ——– ——–
It may seem confusing because many people are accustomed to thinking about fluxes through areas, eg., upward, downward, and net vertical fluxes at various heights.
B.E. Finch: “ Obviously, the TOTAL photons manufactured would only be of similar quantity to the leakage if the IR gases absorbed hardly any photons, which I don’t think is the case.” – perfectly correct, ie., in the limit of zero optical thickness, all absorption cross-sectional area is visible (not hidden by other cross sections) so all the glow emitted escapes the volume.
patrick o twentysevensays
Correction: … the absorption cross section σ_a is the area which would absorb the intensity (= radiance * area facing a direction) that a unit of material net-absorbs. …
patrick o twentysevensays
Clarifications1:
The dependence of blackbody spectral radiance (Bν) on (n_{r,refraction})² is for n_{r,refraction} of the material/space through which the radiance is going. Eg., imaging a glass sphere with n_{r,refraction} = 2 (a bit unrealistic, perhaps, but I want a nice round number), with a perfect antireflection coating; using approx. that n_{r,refraction} = 1 outside it. Embedded concentrically within is a perfect blackbody spherical surface BSS (if necessary, assume its material has n_{r,refraction} ≥ 2). Within the glass, the radiance coming from the BSS is 2² Bν(1) = 4 Bν(1) where Bν(1) is Bν for n_{r,refraction} = 1; BSS looks just as big as it is; let it have radius r_{BSS}. From outside the glass, the radiance coming from BSS is Bν(1); (***I haven’t verified this with computation of the critical angle for Total Internal Refraction (TIR) but I expect that:) if the glass sphere r ≥ 2 r_{BSS} (assuming this avoids TIR of rays from BSS) BSS should appear to have twice the radius and thus 4 times the area that it actually does; the total flux emitted from BSS escapes the glass. If the glass is smaller than there must be TIR for some of the rays coming from BSS; people living on BSS would see a superior mirage.
“I haven’t verified this with computation of the critical angle for Total Internal Refraction (TIR) but I expect that:”…:
Good News – it works! Two right trianges BOG and B’OG, sharing the hypotenuse OG (O = center of spheres; G = point on glass sphere (GS) where ray emitted from B crosses surface); legs BO = r_{BSS} and B’O = r’, and legs from G to a points B (following emitted ray) and B’ (projecting back in direction of refracted ray to where visible edge of BSS would appear from outside GS):
Note: the visible edge of BSS, as would appear from outside GS, is a bit around the backside (from an infinite distance, you would see more than half of BSS at a time); each unit area on BSS is not (generally?) magnified by (n_{r,ref})², but is visible from a wider range of directions.
Note: change in radiance during refraction doesn’t require a curved surface; so long as geometric optics applies (AFAIK), it only depends on n_{ref} – the relation is easily (well, ~) derived for a flat interface, which locally approximates any smooth surface. Thus there is a fundamental difference between magnification of objects behind a lens and of obects within a lens.
Thus, the dependence of blackbody radiance on (n_{r,ref})² is necessary for refraction to not violate the 2nd Law of Thermo. But the only place I’ve seen this dependence on (n_{r,ref})² explicitly stated was in the book “The Physics of Solar Cells” by Jenny A. Nelson:
Clarifications2: https://en.wikipedia.org/wiki/Opacity
…
The above @ https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823793 assumes all atmospheric optical depth is from absorption. Elastic scattering, which (approximately*) conserves photon energy, cannot directly add to emission or absorption but can redirect where absorption occurs (*I presume small changes in energy would be an additional line-broadenning mechanism(?)). Elastic scattering is negligible for LW radiation within the atmosphere AFAIK, though there is some such scattering and reflection at the surface; these are more important for SW photons; although a greenhouse effect could hypothetically be based on scattering. Inelastic scattering … https://en.wikipedia.org/wiki/Inelastic_scattering#Photons (?) AFAIK/AIUI not energetically significant for Earth’s climate, but is important in stars AIUI. https://en.wiktionary.org/wiki/AIUI
Another way to look at fluxes:
The fluxes through an area at a location are composed of contributions from the fluxes, from point of emission to point of absorption, between pairs of volumes. For each such pair, if each volume is sufficiently small as to be approximated as isothermal, yet large enough for the population of molecules/etc. to be statistically significant (– and at LTE/LEDNLIE), the net flux is from higher to lower T (at least if ΔT is larger than sum of approximation errors), but the sizes of the contributions from different pairs vary with changing opacity, so the net flux at a given location can change direction.
(Also, with scattering or reflection, a larger/more area(s) w/could be needed to completely catch the total flux from one volume to another.)
flux density: flux per unit area (through an area)
I intensity: flux per unit solid angle, in a direction
(note the word “intensity” is often used for other things, though)
L radiance: flux density per unit solid angle, in a direction, through an area facing that direction. If you focus at ∞ (infinite distance), then, with some caveats***, radiance corresponds to the brightness you see at a point in your visual field.
spectral ___ – amount of ___ per unit of the spectrum (at a given point in the spectrum). (PS I often leave out the word “spectral”, relying on context.)
…
I forgot to mention that its specific purpose (apart from I think the general description is a logical way) is to (correctly) de-couple by IRRELEVANCE memes regarding the split of surface energies into air into sensible, water-latent, LWR from the actual reality by correctly coupling sensible, water-latent & LWR and attack Junk memes of the variety “(gunf)2nd Law of Thermodyamics(gunf)”, “the surface heats itself”, “the big atmospheric circulation is thermals not LWR which is a minor player!” with a minor local aside (far lesser junky than the preceeding) of our JCM’s discussions of its gut feelings about upwelling, downwelling surface LWR amounts, the complex crinellations and rich Corinthian leather of the turbulent surface layer, and some (not all) aspects of evaporation latent heat. I realized in July 2018 when I took a longer look on the couch (almost an hour I think) at “greenhouse effect” than in 2016 and realized that the nonsense “LWR up from surface gets re-emitted, s0 50% goes back into surface” was an utter boon to Koch Industries, which I’ve definitely seen proved the last 12 years in absurd disinformational videos, and I quick tried a trial balloon to discuss on Realclimate about that nonsense in July 2021 or July 2022 (or in some month of some year) but it got Boreholed,
Barry E Finchsays
Some hyper-advanced mathematics from me to boast my hyper math skills & hyper science skills simultaneously, all novel thought and nothing stolen:
* A 7-year doubling scenario curve exceeds 1 m around 2055 and 2 m around 2061;
* A 10-year doubling scenario curve exceeds 1 m around 2063 and 2 m around 2072;
* A 13-year doubling scenario curve exceeds 1 m around 2070.
* A any-year doubling scenario is totally meaningless because it contains no ice sheet dynamics whatsoever and the ice must get itself below sea level in order to raise sea level.
I’m just plain showing off hyper-advanced mathematics & science
Geoff Miellsays
Barry E Finch: – “A any-year doubling scenario is totally meaningless because it contains no ice sheet dynamics whatsoever and the ice must get itself below sea level in order to raise sea level.”
In the YouTube video titled Ep. 2 | Why is Greenland melting so fast? Ft. @JasonBoxClimate, published 15 Jun 2023, duration 0:09:16, included the following discussion:
06:34 Dr Ella Gilbert:And can we say what we’re already committed to from Greenland?
06:38 Prof Jason Box:Right, we studied the ice loss commitment from Greenland, and the variations from year to year, they actually point squarely at an ice loss commitment that right now stands at at least 27 centimetres of global sea level rise, but that’s if the climate stayed constant up to 2019. Climate will continue warming and so the ice loss commitment grows. In a high emissions scenario, Greenland’s ice loss commitment reaches more than one metre by end of century. So we have some time to get off of that high emissions scenario and basically halve the, the sea level commitment from Greenland to about half a metre by end of century.
07:31 Dr Ella Gilbert:So what would a lower melt, or perhaps more optimistic future path for this century look like in Greenland and how would that differ from a more pessimistic view?
07:44 Prof Jason Box:Say, like the difference between something close to the Paris climate agreement scenario and the high emissions scenario, is about a factor of two for Greenland’s sea level contribution. So there’s a lot of value in finding ways to reduce carbon emissions and get into carbon dioxide removal.
08:08 Dr Ella Gilbert:So, there’s the answer: the biggest loser in the Greenland melt story is surface melt, and a lot of it happens when weather patterns conspire to bring much warmer air up from the south a drive extreme melting events. On the surface of it, that doesn’t sound great, especially given that our atmosphere is heating up extremely rapidly and we’re seeing more and more of those extreme events. However, because temperatures in the atmosphere can change much faster than in the ocean, in some ways it’s a bit of a silver lining because it means that melting can slow down pretty quickly too once we reduce emissions and turn down that dial on the climate heating. Shifting into that lower emissions world that Jason spoke about is still possible and even though it still means some degree of further sea level rise, it’s far preferable to the alternative. But something we REALLY need to steer clear of if we’re going to minimise ice losses from Greenland is tipping points, which – funnily enough – is the subject of our next video. https://www.youtube.com/watch?v=tRtqOTtsCr8
The discussion above is just talking about Greenland’s contributions to SLR:
* circa 0.5 m by 2100 for holding at or below +2.0 °C global warming level;
* circa 1.0 m by 2100 for +4.0 °C global warming level.
Add in the Antarctic’s contributions to SLR and ocean thermal expansion and I’d suggest more than a metre of SLR is inevitable by 2100, unless we/humanity find some way to cool down the planet fast.
The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.
“The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.”
Yes to get above 1 metre SLR this century, and certainly to get above 2 metres, looks like it would indeed need exponential growth of SLR. Exponential growth wont happen at scenarios of 2 – 5 degrees C of warming and from thermal expansion of the oceans, and melting of glaciers from the top down, and current ice sheet dynamics.This is generating a quadratic growth curve over this century. Im not an expert by a long way, but all that is fairly obvious maths and physics.
We have seen short periods of exponential growth in Greenlands surface melting but this even if it continues, looks insufficient to lead to exponential growth in global SLR. MAR posted some histortical numbers on all that. Although its still adding to SLR and the cumulative effects do add up ominously.
To get to exponential SLR and multi metre SLR this century requires a change in ICE SHEET DYNAMICS. A disintegration of the ice sheets in Antarctica and Greenland. My recollection is that James Hansens findings are that above 2 degrees you kind of reach a tipping point where glaciers start to dramatically speed up their flow into the oceans and the face of glaciers start collapsing at a very enhanced rate. This in turn relates to how glaciers are grounded. This process is exponential for a limited period until it stabilises, but hence you get exponential SLR this century and possibly into next century. I think hes very credible on this mechanism in principle. He calculated that 5M SLR is possible this century.
The paleo record has periods of multi metre SLR per century, like meltwater pulse 1a where you had 4M per century, starting rather abruptly and ending quite abruptly after about 5 centuries, and then reverting back to about 0.5M per century for a long time. This abruptness suggests a change in ice sheet dynamics. However there was also more ice sheets back then to melt so its hard to know how much ice sheet dynamics contributed but clearly it was significant because nothing else would easily explain the abruptness of the change.
Its hard to be sure what will happen this century and whether SLR would be as much as 5M, because of knowledge gaps around exactly how glaciers will behave. We know a change in dynamics is very likely but its hard to quantify the rate of change precisely. But I believe we know enough to know rapid multi metre SLR is very possible and only a fool would completely dismiss Hansen.
I think we are heading to 2M SLR this century, all things considered, and if we dont cut emiisions to zero by 2050. But To me quibbling over whether we have 1, 2, or even 5 metres SLR this century may not be the main point. Because anything above 1 metre looks very serious and ;possible, so thats enough to get me worried and reason enough to take action. We simply cannot afford to play Russian Roulette and hope we can do nothing and dodge a bullet because the consequences of rapid multi metre SLR are too large. Just my two cents worth.
Sabinesays
to Nigelj
you say – “He calculated that 5M SLR is possible this century.”
Did he? Can you remember where? Because my memory, and I could be wrong, was in the Ice Melt paper he said 5m slr per century was the fastest rate from historical paleo evidence.
Not that 5m by 2100 was possible or likely. Of course it’s all academic and not that important either way. No one of note seems to be taking his work seriously anymore. Unfortunately.
nigeljsays
Sabine you ask where Hansen calculated SLR could be 5M this century. I just cant recall exactly and a quick google didnt help find it. It was about ten years ago at least and I think it was media commentary on one of Hansens studies, or maybe it was on some BOE calculations.
But I found this commentary from 2016 fyi. Its not what I read, and it seems more recent, but its saying 5M of SLR may happen over a period of 50 years and hes tallking about this potentially happening in our future:
“All Eyes on the Oceans: James Hansen and Sea Level Rise”
By Sasha Wright
“On July 23,(appears to be 2016) James Hansen and 16 co-authors posted a discussion paper on an open-review website about sea level rise and climate change. The article has garnered massive attention around the internet and scientific communities — both for its content and for the unconventional manner in which it waspublished. The authors bring special attention to a particular aspect of global climate change that often isn’t discussed. Namely, global sea level rise. While many of us discuss the catastrophic impacts of droughts, flooding, and dwindling food supply related to climate change, the authors emphasize that up to 5 meters of sea level rise may happen over the course of 50 years, carrying with it the “economic and social cost of losing functionally all coastal cities…” Seeing as the more conservative IPCC report puts this estimate closer to 1 meter by the year 2100, this news is making an impact. ”
(the article then goes onto discuss the SLR mechanism)
The commentary appears to be based on The paper ” Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2◦C global warming is highly dangerous, Hansen and others, 2015″
I just take a general interest in climate change. I just wanted to make the point that the IPCC SLR projection of 1M SLR this century is based on a gradual melting process and follows a quadratic curve, and to get to multi metre SLR as high as 5M within this century, would require some sort of step change process involving ice sheet dymanics, and my recollection is Hansen said it would involve exponential growth. Although as John Pollack points out other curves could also get to multi metre SLR. It intuitively looks to me like it would be quite a steep curve and a fairly abrupt departure from the trend of the last couple of decades.
Geoff Miellsays
Nigelj: – “I think we are heading to 2M SLR this century, all things considered, and if we dont cut emiisions to zero by 2050.”
I’d suggest it requires more than just cutting GHG emissions to zero well before 2050. It also requires atmospheric carbon drawdown, and maintaining Arctic sea ice cover.
It seems +1.6 °C global warming threshold is the best estimate for the tipping point for the Greenland ice sheet. The longer the Earth System stays at or above this threshold the more difficult it would be to avoid the collapse of the Greenland ice sheet. I’d suggest the Earth System will likely be in that territory sometime in the 2030s. https://www.sciencedaily.com/releases/2012/03/120312003232.htm
I’d suggest lethal humid heat and worsening global food security are likely to manifest well within the remainder of the first half of this century as the Earth System continues to warm further, progressively worsening the lives of tens to hundreds of millions to perhaps billions of people, well before SLR likely gets to & above the 1 m level sometime in the second half of this century. https://www.nature.com/articles/s41893-023-01132-6 https://x.com/rahmstorf/status/1661450321766371329
Nigel: The paleo record has periods of multi metre SLR per century, like meltwater pulse 1a where you had 4M per century, starting rather abruptly and ending quite abruptly after about 5 centuries
Nigel, I don’t think this is a good analogy. The “multimeter” meltwater pulses you speak of didn’t come from currently melting ice, but from breaking of the ice dams, letting the meltwater accumulated there during the previous centuries in giant lakes at the edge of the N. American ice sheet. There are no giant lakes that have accumulated the meltwater over many centuries on Greenland or Antarctica. And in the context of the current discussion – those meltwater SLR pulses do not seem to be exponential over their duration of the pulse.
Similarly, the abrupt end of them may not be instructive for near future either
1. the rate of the meltwater supplied to N.Atlantic then – was MUCH higher than today – which may be the difference between shutting down the AMOC, resulting in a period of flat SL then, and possibly only weakening of AMOC now.
2. And even if we have massive melting now – it would be from Antarctica – shutting down local downwelling around Antarctica, which is only a minor contribution comparing to the AMOC downwelling in the N. Atlantic – i.e. the location next to the source of N. American ice sheet during the past meltwater pulses.
To sum up – the mechanism and therefore the RATE of the future SLR almost certainly will be different than those during the meltwater pulses during the deglaciation.
Nigeljsays
Piotr.
You’re right that meltwater pulse 1a (with 4m SLR per century) is not a great anaology for our situation, but I think we can still learn something from it. The wikipedia article on meltwater pulse 1A says there is still uncertainty about whether the principal cause is 1) the laurentide ice sheet and the related mississippi river flood events (ice dams breaking) or 2) the antarctic ice sheet melting or 3) the Fennoscandian and Barents Sea Ice Sheets.
The commentary did mention that theres evidence Antarctica contributed 2M per century due to rapid local warming. This is the reason I said I think 2M SLR per century is a more realistic worse case scenario for our times. Its also a reason to believe a 1 metre prediction of SLR by 2100 is too conservative.
Piotrsays
Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today,
and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.
With two past forcings absent today, and the third likely very different – any extrapolation of the past rates of SLR on the today or future ones – is _extremely_ questionable, if not outright misleading – promising insight from the past where, due to the differences with today, there is none.
Mal Adaptedsays
Tangentially, I enthusiastically recommend the 1992 book by the late E.C. Pielou titled After the Ice Age: The Return of Life to Glaciated North America. The author, a Canadian statistical ecologist, devoted chapters to what was then known about the hydrology and ecosystems of those giant periglacial lakes, up to their catastrophic drainages. The whole book is fascinating, a masterpiece of historical ecology. The woman held a vast store of facts in her brain, and connected them all together into a powerfully explanatory, broadscale narrative. Events may not have proceeded exactly the way she envisioned, but the story is irresistible to anyone who’s ever wondered about how that recent episode of natural climate change played out on the landscape.
John Pollacksays
GM: The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.
Geoff, I’m puzzled as to why you insist on framing SLR in terms of an exponential function. The math is simple, but wrong and misleading. The quote above illustrates part of the problem. Having to choose an AVERAGE doubling time implies that you aren’t really talking about a rise described by a single exponential function. There is a single exponential function with a real, positive exponent that will produce a rise of 1m at 2100. If we were actually on that curve, there would be a particular doubling time, and no need to seek an average.
What we are all really talking about is some sort of SLR that starts out small with the observed values, but comes to increase rapidly before 2100. (Even the 2100 date is arbitrary, because the process will continue for centuries or millennia beyond 2100.) There are an infinity of polynomial functions that will produce this behavior in one way or another. Statistically, starting with a small rise and additional noise means that you wouldn’t be able to pick one over another from the observed data.
On another level, even having a single function to describe SLR is misleading, because the rise depends on both future human behavior for emissions and mitigation, as well as ice dynamics. Any function we pick to fit the available curve will lack predictive skill. In fact, any will be false if extended long enough, so you also need a way to determine when the curve will cease being applicable.
I strongly agree with the overall concern that we and the planet are in big trouble with sea level rise, and setting up for a very rapid rise. This is based on solid evidence from the last interglacial. Sea levels ended up shockingly higher than present values, and at least part of the rise was rapid – starting at levels already about 2m higher than present values. This occurred with CO2 levels no more than 300 ppm, but with a higher obliquity of axial tilt than present values, The higher obliquity resulted in relatively more solar energy incoming in the polar regions, and less in the tropics, than at present. Perhaps this is why we are already seeing coral deaths due to warm tropical oceans, while the ice sheets are just beginning to melt rapidly. In addition, both the meteorology and ocean currents will be at least somewhat different with hotter tropics and cooler poles than last time around, about 120,000 years ago.
Geoff Miellsays
John Pollack: – “Geoff, I’m puzzled as to why you insist on framing SLR in terms of an exponential function.”
Per the Hansen et al. (2023) paper titled Global warming in the pipeline (bold text my emphasis):
Discussion [184] with field glaciologists¹³ 20 years ago revealed frustration with IPCC’s ice sheet assessment. One glaciologist said—about a photo [185] of a moulin (a vertical shaft that carries meltwater to the base of the Greenland ice sheet)—‘the whole ice sheet is going down that damned hole!’ Concern was based on observed ice sheet changes and paleoclimate evidence of sea level rise by several meters in a century, implying that ice sheet collapse is an exponential process. Thus, as an alternative to ice sheet models, we carried out a study described in Ice Melt [13]. In a GCM simulation, we added a growing freshwater flux to the ocean surface mixed layer around Greenland and Antarctica, with the flux in the early 21st century based on estimates from in situ glaciological studies [186] and satellite data on sea level trends near Antarctica [187]. Doubling times of 10 and 20 years were used for the growth of freshwater flux. One merit of our GCM was reduced, more realistic, small-scale ocean mixing, with a result that Antarctic Bottom Water formed close to the Antarctic coast [13], as in the real world. Growth of meltwater and GHG emissions led to shutdown of the North Atlantic and Southern Ocean overturning circulations, amplified warming at the foot of the ice shelves that buttress the ice sheets, and other feedbacks consistent with ‘nonlinearly growing sea level rise, reaching several meters in 50–150 years’ [13]. Shutdown of ocean overturning circulation occurs this century, as early as midcentury. The 50–150-year time scale for multimeter sea level rise is consistent with the 10–20-year range for ice melt doubling time. Real-world ice melt will not follow a smooth curve, but its growth rate is likely to accelerate in coming years due to increasing heat flux into the ocean (Fig. 25).
John Pollack: – “The math is simple, but wrong and misleading. The quote above illustrates part of the problem. Having to choose an AVERAGE doubling time implies that you aren’t really talking about a rise described by a single exponential function.”
I stated on 8 Aug 2024 at 10:12 PM:
Real-world ice melt will not follow a smooth curve.
Please read what I’ve previously stated. That way, there’s perhaps less chance of misunderstanding.
I’d suggest the rate of SLR acceleration will likely to be a composite of multiple doubling times over the coming decades while the energy inputs into the Earth System, and more particularly into the cryosphere and oceans, increase. Various tipping points with the Greenland and Antarctic ice sheets are also likely to vary the doubling times.
The UN Sustainable Development Solutions Network (SDSN) published on 3 Nov 2023 the YouTube video titled An Intimate Conversation with Leading Climate Scientists To Discuss New Research on Global Warming, duration 1:12:23. From time interval 0:17:03, James Hansen said:
“The 1.5 degree limit is deader than a doornail, and the 2 degree limit can be rescued only with the help of purposeful actions to effect Earth’s Energy Balance. We will need to cool off Earth to save our coastlines, coastal cities worldwide, and lowlands, while also addressing the other problems caused by global warming.”
From time interval 1:04:03, James Hansen on tipping points said (bold text my emphasis):
“Yeah, the most important tipping point is the, the Antarctic ice sheet, and in particular the Thwaites ah, Glacier, which who’s grounding line has been moving inland at a rate of about a kilometre per year, and ha, in another 20 years, it will reach a point where it, it… the, the um, bed ah, is so-called ah, retrograde bed, so it gets deeper. The Antarctic ice sheet sits on bedrock below sea level, but it gets deeper as you go towards the centre of the continent, and it gets… It hits a canyon in about 20-years if we continue at one kilometre ah, per year. When it hits that canyon you’re going to get very rapid disintegration of that glacier, which is basically the cork that’s holding ah, a lot of the West Antarctic ice ah, in the bottle. So we don’t want to get there. And if we want to prevent, to slow down, and even stop the melting of the Antarctic ice sheet we have to cool off the planet. That’s, um… And, and we need to do that because, hah, more than half the large global cities in the world are on coastlines, and there are a lot of lowlands. Ah, so, that, that’s the tipping point which ah, I think dominates. But it so happens that there’s so many other ah, climate impacts that we would be getting to see and it would be much more if we go beyond two degrees, that there are many reasons to want to cool off the planet. If we want to keep a planet that looks more or less like the one that has existed the last ten thousand years, we actually have to cool off the planet back to a Holocene-level temperature, and that’s possible, but it’s not easy.” https://www.youtube.com/watch?v=NXDWpBlPCY8
For the indicative GMST anomalies, the purple coloured areas shown in the gif animation are regions where the mean annual temperature (MAT) is projected to be above 29 °C, which is considered to be no longer habitable for humans (or at least that’s the situation without effective air conditioning). https://x.com/rahmstorf/status/1661450321766371329
Piotrsays
Geoff Miell, quoting Hansen: “ Concern was based on observed ice sheet changes and paleoclimate evidence of sea level rise by several meters in a century, implying that ice sheet collapse is an exponential process ”
The problem is with that “ implying
An extremely complicated phenomenon like sea level rise is NOT LIKELY to be described adequately by a simplistic mathematical formulation ( a straightforward exponential function, i.e. with a fixed exponent).
Further – as pointed out by John Pollack and then me – the pattern and mechanisms of the past rapid SLRs during deglaciations – are very different than those today – hence one can’t extrapolate past situations and the coefficients of the exponential function from the past data, onto the current ones.
Which confines us to the recent data (the last decades) – yet the very nature of the predictions based on the exponential models is that they are hugely sensitive to even small errors in the calculation of the exponential function coefficients from the early data.
Geoff Miellsays
Piotr (at 19 Aug 2024 at 9:02 AM): – “An extremely complicated phenomenon like sea level rise is NOT LIKELY to be described adequately by a simplistic mathematical formulation ( a straightforward exponential function, i.e. with a fixed exponent).”
It seems to me you have demonstrated selective blindness again.
Repeating my earlier comments again:
Real-world ice melt will not follow a smooth curve.
I’d suggest the rate of SLR acceleration will likely to be a composite of multiple doubling times over the coming decades while the energy inputs into the Earth System, and more particularly into the cryosphere and oceans, increase. Various tipping points with the Greenland and Antarctic ice sheets are also likely to vary the doubling times.
It seems to me you persistently demonstrate a habit of ignoring (and/or denigrating) comments that are inconvenient for your narratives.
What is known:
* The long-term rate of sea-level rise has more than doubled since the start of the satellite record, increasing from 2.13 mm/y between 1993 and 2002 to 4.77 mm/y between 2014 and 2023.
* Acceleration: 0.12 ± 0.05 mm/yr²
* The rate of SLR is currently around 5 mm/year.
Figure 6 in the WMO’s State of the Global Climate 2023.
Arguably one of the foremost experts on Greenland ice sheets and glaciology, Prof Jason Box, suggests for global mean SLR levels:
I think it would be foolish to ignore/dismiss the warnings from multiple credible sources that SLR is accelerating and will be relentless for centuries to come, unless we/humanity take steps and begin to cool planet Earth back to Holocene levels within the next few decades.
Piotr (at 19 Aug 2024 at 9:02 AM): – “Which confines us to the recent data (the last decades)”
Nope. It also includes all available data including the paleo-historical record. What has happen in the past should inform future possible outcomes. As Professor Schellnhuber put it in response to a question by Jørgen Randers after Schellnhuber’s 2018 Aurelio Peccei Lecture: “…simply because this is our reality lab, ja?” https://youtu.be/QK2XLeGmHtE?t=2781
It seems to me you (among some others here at this blog) are cherry-picking some data to support your ideological narrative and ignoring/denigrating other data that’s inconvenient.
John Pollacksays
Okay, I believe I get it now, Geoff. There’s a precise mathematical/scientific definition of an exponentially rising curve. Then, there’s a much looser colloquial concept of an “exponential rise” with a doubling time that may or may not be consistent or relevant, and which may or may not contain tipping points, etc. You prefer the colloquial usage to inform us in this scientific blog. If we find it imprecise or confusing, we can just read all about your intended meaning.
I feel rather like when I go to a store to pick up a particular item. However, I don’t find it in the accustomed section. I can look all over the store for it, and probably find it still. Perhaps the prolonged search was the intended purpose of moving it around. Or, it may not be there at all. I will keep the experience in mind when deciding whether to visit the store in the future.
So be it.
Piotrsays
Geoff Miell: It seems to me you have demonstrated selective blindness again. Repeating my earlier comments again: “Real-world ice melt will not follow a smooth curve”.
How to eat cake and lecture others on being “selectively blind” for seeing you … chomping down the cake…
Geoff Miell, eating the cake – quoting Hansen:
“ Concern was based on observed ice sheet changes and paleoclimate evidence of sea level rise by several meters in a century, implying that ice sheet collapse is an exponential process ”
“Exponential” means f(t)= f(o)*e^(rt). As such, it has a SINGLE doubling time. To quote Geoff Miell lecturing others: “That’s simple mathematics and logic”
The exponential formulation may be a useful where there is only a single process dominating – such as an exponential growth of population, or exponential decay of radioisotopes. Where there are many important interactions – exponential formulation is useless, or outright – misleading – promising insight, where there is none, and resulting in INFLATION of a given process over time – the exponential function for r>0 it produces MASSIVE increases over time – hence it is a function of choice for those who are invested in as large SLR as possible, for instance:
==== Geoff Miell : For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 156.7 mm (or 244.1 mm SLR relative to the Jan 2000 level)
2050: 383.0 mm (or 470.4 mm SLR relative to the Jan 2000 level)
2060: 835.7 mm (or 923.1 mm SLR relative to the Jan 2000 level)
2070: 1741.0 mm (or 1828.4 mm SLR relative to the Jan 2000 level)
By 2100, voila – 14 metres!
=====
And no – you don’t account for the multiple complicated interactions determining real-world SLR by simply … repeating the same exponential calculation, but a with a slightly different coef. r, as in:
Geoff Miell : For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024: …. For a 13-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024: ….
All you have done – was to calculate two separate scenarios for two slightly different values of r. Doing so does NOT mean that you used “ a composite of multiple doubling times.
In fact have you used VARIABLE r – it would not longer be “exponential process” (Hansen).
So, in the light of the above – who of us two has “demonstrated selective blindness again, Mr. Miell ?
Nigeljsays
Piotr. I normally like your clear, persuasive comments, but your post replying to GM is a bit hard to follow. For example Hansen did mention he thought the past collapse of the Antarctic ice sheets was an exponential process. Im assuming you accept this but are arguing that it would not cause exponential SLR because of all the other factors contributing to SLR. Which sounds correct. Hope I have that right. It would however obviously cause an acceleration in SLR .
The exponential process might have been due to how glaciers move towards the oceans and potentially speed up. Some geological processes do have exponential growth for example how landslides develop as below. So its not confined to things like population growth or financial processes (not that you said that). So Hansen could be right. Refer:
You previously talked about melwater pulse 1a (causing 4M SLR per century) and mentioned circumstances were different back then so we cant assume we will get 4M or more SLR in our futures and I accept youre right overall. There was far more ice back then for a start.
However you also mentioned MWP 1a was caused by ice dams breaking. Please note that the Wikipedia entry on meltwater pulse 1a (4M SLR per century) says there is still controversy over the main cause. The commentary says it could be ice dams breaking related to the laurentide ice sheet, or the Antarctic ice sheet disintegrating or other ice sheets disintegrating.
The commentary also said that there is evidence the Antarctic caused 2M of SLR per century back then. I think this is an important point buried in the commentary. It might be the thing we should pay a lot of attention to. It suggests we could have 2M SLR per century, perhaps this century, especially when you factor in ice loss from other regions and causes. I’m a bit sceptical of claims we could have 4-5 M SLR this century.
Piotrsays
Re Nigel Aug 22:
As for your other question, on the meltwater pulse 1a – I answered it in the post to you
send on the same day (Aug 22) (that’s probably why you didn’t see it).
So here it is again:
====
“Piotr Aug 22:
Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today, and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.
With two past forcings absent today, and the third likely very different – any extrapolation of the past rates of SLR on the today or future ones – is _extremely_ questionable, if not outright misleading – promising insight from the past where, due to the differences with today, there is none.
=====
Nigeljsays
Piotr
“Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today, and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.”
I agree that we dont have the huge laurentide, fennoscandian and Barrents sea ice sheets today. I do actually realise conditions were generally different back then, which is why I never suggested in any comments we would be seriously likely get 4M SLR / century like meltwater pulse 1a, and that it would more likely be something like 2M.
However you are presuming all or part of the Antarctic ice sheet easy to melt are long gone. Im not sure what is meant by easy to melt. We can be reasonably sure the ice sheets and glaciers were more extensive but Its not clear why that would make them easier to melt.
All I’m saying is it appears that MWP1a had a rapid onset and multimetre SLR per century of 4M and that it looks like the Antractic may have contributed about 2M of this SLR. Something triggered that rapid Antarctic melting process and its been suggested it was warming Antarctic oceans and speeding up of glaciers moving towards those oceans. Such conditions look like they exist today and increasingly so in our futures if we dont cut emissions. Plenty of studies on all that. We cant be sure it would generate exactly 2M SLR, but for me its a WARNING that we may be on the verge of triggering rapid and substantial SLR.
Piotrsays
Nigel Aug.27: “You are presuming all or part of the Antarctic ice sheet easy to melt are long gone. Im not sure what is meant by easy to melt.
Those which at the edges – iceshelves and glaciers along the shore – that are most exposed to the outside changes, particularly ocean water – they are last to grow during the glaciation and first to melt during the deglaciation stage.
Thus in the late stage of natural deglaciations (as we would have been if not for our HGH emissions) – there is not much left to be easily melting – melting kms-thick ice cap on land (i.e. not exposed to the ocean waters which melt ice much easier than air) and having 100s of 1000s of km to go horizontally before being able to add to the SLR by calving – won’t be as easy/quick.
NIgel: “ Something triggered that rapid Antarctic melting process and its been suggested it was warming Antarctic oceans and speeding up of glaciers moving towards those oceans. Such conditions look like they exist today and increasingly so in our futures if we dont cut emissions.
Nigel, my point is that the conditions TODAY are nothing like those in the early stages of deglaciation (14ky ): since today you don’t huge amount of easily=quickly meltable ice the way you had early in deglaciation 14ky => you should not expect anything comparable in term SLR RATES.
See also my 24 Aug 2024 at 7:31 PM post (near the end of this monthly thread) –
“Still warm ( 21 Aug 2024): “The West Antarctic Ice Sheet may not be vulnerable to marine ice cliff instability during the 21st century ‘ Morlighem et al.”
Past is a good predictor of the future only if the future conditions/patterns are like those in the past.
Again, I appreciate your explanations of the differences between present situation and situation before meltwater impulses. I think that all arguments you brought against the threat of a quick multi-metre SLR during 21st century sound reasonably and are quite persuasive.
In case that you could be willing to cease your fire and seriously deal with a question from a sentenced denialist like me, I have one, regarding the longer-term perspective of the Antarctic ice sheet.
On one hand, there are concerns (please correct me, if I am wrong) that already the present atmospheric concentrations of GHGs can – provided that they should persist for thousands of years – may cause a global temperature increase substantially exceeding 2K against preindustrial level. It seems obvious that such a warming may cause substantial thawing of the Antarctic ice sheet, and it seems even more obvious that the thawing should be even stronger if the present GHG forcing further increases.
On the other hand, it was mentioned several times in discussions herein on RC that (at least during polar winter), the GHG effect in fact cools Antarctica. If so, I would like to ask if this fact may suggest that thawing of the majority of the Antarctic ice sheet – whereby I mean the part which is not in direct contact with ocean – may not be a such straightforward consequence of the increased greenhouse effect as it might have looked on the first sight?
Are there already detailed studies that assess how various mechanisms contributing to ice deposition and/or thawing in Antarctica may change as a result of the increased greenhouse effect itself and of its feedbacks like global ocean warming and possible changes in ocean streams?
Greetings
Tomáš
Piotrsays
re: John Pollack Aug. 17
Great points, John, both on problems with using an exponential function to describe future SLR, and on the difference between the current melting and the one in the last interglacial – the latter triggered by orbital warming of the Arctic (in summer), the current one seeing much more “diffused” warming from surplus CO2. In addition:
– there was also much more “disposable” ice then (worth of 135m SLR), only < half of that left now in Greenland and Antarctica
– as I already indicated to Nigel – SLR may be modified by shutting down the downwelling in N. Atlantic that drives AMOC. You CAN do it when most of the meltwater comes from N. America (then), not when most of it is to come from Antarctica
– the past deglaciations started with much more of sea ice in N. high lats than we have today – hence the ice albedo -T feedback in the past have much more seaice-area to work with than it has today.
One can't walk into the same river (here: the same SLR mechanisms, ice patterns, and thus SLR rates) twice.
John Pollacksays
Piotr, I agree that the situation is different from the last interglacial (LIG), for the reasons you highlighted and others – especially the difference in GHG levels and causes.
For clarity, I was referring to the warm period after the LIG had already begun. My thinking is heavily influenced by : O’Leary, M., Hearty, P., Thompson, W. et al. Ice sheet collapse following a prolonged period of stable sea level during the last interglacial. Nature Geosci 6, 796–800 (2013). https://doi.org/10.1038/ngeo1890
The title of the paper and the abstract provide a decent summary. After a period of interglacial warmth, in which the SL was fairly stable – already about 3m higher than current values – there was an additional rapid rise to around +9m. This clearly required more melt than at present even at the beginning of the LIG, followed after a long interval by a fairly abrupt further disintegration of ice sheets.
As Killian noted upthread, the ultimate rise required near complete melting of the Greenland Ice Sheet, and also around the periphery of Antarctica. There is at least one mechanism that can operate to produce rapid further melting even during a warm interglacial. I suspect we’re on track to find out what it is by experience before we succeed in arresting the process. There are several candidates, but I’m not aware that any has emerged as the culprit in the LIG.
Piotrsays
John Pollack: As Killian noted upthread, the ultimate rise required near complete melting of the Greenland Ice Sheet
Thanks for the correction, Piotr. It was also the 416k event that Killian was referring to upthread.
However, I still think that most of the Greenland Ice Sheet would have to melt to get to +9m SLR, as well as some chunks off the Antarctic Ice Sheet.
Killiansays
Piotr, their data *must* be incorrect. The new paper discussed in the article I linked found a complete or nearly-complete melt of Greenland 416k years ago. That’s 6 to 7 meters of SLR.
SL levels for that interglacial will need to be recalibrated – or the latest paper found to be flawed. Both cannot be true.
Piotrsays
John Pollack “ Thanks for the correction, Piotr. It was also the 416k event that Killian was referring to upthread. However, I still think that most of the Greenland Ice Sheet would have to melt to get to +9m SLR
which opens the door to even more questions – why no ice-free Greenland in the subsequent interglacials, even though they seems to have HIGHER SL than 416k???
In fact, it looks like the melted greenland 416k seems to have … approx. todays SL
– while you “+9m SLR” is likely to apply to the last interglacial. (LIG) i.e. period WITHOUT major de-icing of Greenland.
Stranger still for the current extrapolation of deglacation rates onto the near future – the slope of SLR is steeper at LIG with ice on Greenland, than at 416k with ~ ice-free Greenland.
Obviously deglaciation of Greenland was NOT the reason for those 2m/century rates at LIG.
Another surprising to me thing on this graph is that (with somewhat of an exception for last Ice Maximum) – the maximum drops in SL during ice maxima preceding deglaciations – gets …. shallower and shallower with each cycle. meaning that there is more ice. Thus I would expect much more complete de-icing of Greenland in LIG – since having started from much higher SL it would have more time to melt Greenland ice, before the factors terminating interglacial kicked in, than the 416ky had.
All this is to say that during each deglaciation the factors affecting SLR may have been in different combination – so one should be very careful when extrapolation past RATES onto the future in which the drivers of change are very different than in the past.
Sabinesays
Dear Barry,
about your issues “because my comment above is Censor-Deleted by GoogleyTubes (as per >70% for my science comments) ”
Look a while back I too was having my comments delayed on youtube videos. I was baffled. I rarely comment at all. I kept trying different things, and then something stuck me – it was the comments I made that included URLs in my comments.
See, I was making a comment and sharing good references for others to follow. But that in itself was the cause to have my comments deleted. I don’t know when Youtube changed their system to block such things, because in the past I don;t recall it ever being an issue.
Try it yourself – make two comments the same but include a website or youtube url in one, and see what happens when you post them.
Geoff Miellsays
Sabine: – “Look a while back I too was having my comments delayed on youtube videos.”
Ditto. And also some comments simply deleted almost instantaneously.
‘Clean’ YouTube URLs seem to be okay but not too many in the single comment. “Clean’ URLs mean non-referred, shortest possible YouTube URLs.
Other URLs can be problematic. Some work; many don’t. I’ve found if one needs to refer to a paper then just quote the publication, date, author, title/headline, and don’t include the URL. If it’s a reference to a website, quote the website name, date, etc.
Twitter/X URLs seem to be a no-no.
Some people are loath to click on any links.
Piotrsays
Tomas Kalisz: “I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes”
On its own – not; in the context of your and JCM activity on this forum – it is:
Your never accepting answers that don’t fit your deniers narrative (“Anything but GHGs”) , your cherry-picking only those parts of answers that you can misrepresent as supporting your claims, and your incessant sealioning (“ a type of trolling [by] pursuing people with relentless requests for evidence, often tangential or previously addressed, while maintaining a pretense of civility and sincerity (“Thank you for your reply.”). It has been likened to a denial-of-service attack targeted at human beings – are all characteristics of a troll..
And since you. Tomas Kalisz, have been trying for more than a year to seed doubt in climate science, and distract the attention from the urgency of the reduction of GHGs – you are either a paid troll, or “ a useful idiot of fossil fuel oligarchy, and tyrannies that depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad: by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.“..
By their fruits, not their protestations, you shall know them. Particularly that the lady doth protest too much.
I think that, based on your repeated statement, I can now summarize the discussion as follows.
You believe that
1) my questions asked on this forum discredit climate science,
2) for this reason, joining my request to the hosts of this website would have enhanced the destructive effect of my questions and should be therefore avoided, even in case that the request perhaps could be relevant per se.
Please correct me if I misinterpreted your replies.
For the sake of clarity, I would like to summarize my position as well.
As I wrote in my previous reply, I believe that a sound, healthy science has to be aware of existing knowledge gaps, and strive to direct research thereto. I do not think that admitting the existence of knowledge gaps is a sign of weakness of an individual, an institution, or a discipline, and that it might undermine credibility thereof.
Rather oppositely – I see as quite suspicious, if someone perceives questions as a threat. In such cases, I will take any advice from this person and/or institution with a decent portion of caution.
I think we can close our exchange now, because there seems to be no common basis on which we could discuss. If I understood you correctly, there is no need for a continuation.
Best regards
Tomáš
Davidsays
Tomáš, in reply to your response to me on 10 August:
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823654
.
You wrote: “As regards your question why I do not resolve my question(s) myself by my own research, I must reply that as a chemist, I do not have the necessary training for climate modeling. And, more importantly, I am afraid that doing any research of this kind is in fact beyond my capabilities.”
I owe you an apology. I was operating under an incorrect assumption regarding your motives as your statement to me that “your open question” is seeking an answer from “climate science professionals,” of which I am not, makes clear to me. You don’t understand why Real Climate’s (RC) haven’t responded to your pleas for addressing your “open question if there still may be a knowledge gap regarding the relationship between water availability for evaporation on one hand and climate sensitivity towards other forcings on the other hand…”
Your subsequent comments to Piotr and Radge Havers regarding your expectations of a reply from RC’s hosts are illuminating. As they both correctly point out, the hosts are under no obligations to offer replies to yours, mine, or any other commentators questions, pleas, or laments. Our hosts make no such claim that they will answer any or all inquiries. RC is a valuable and useful asset as is (including the monthly U.V.’s) and all the hosts have professional lives that keep them quite busy I would guess.
With this in mind, why you keep asking for a reply and expressing your dissatisfaction at not receiving one, and worse using a lack of a reply to make naked assumptions about the attitudes of RC’s hosts, other commentators here (if they won’t join your pleas), and the field of climate science in general, is patently unfair in my opinion.
As there are literally thousands of climate science professionals of one type or another around this old globe, I admit I’m curious to know if you have or are planning to put your questions to any others in the field? If so, please share your results when you receive such.
And if you’re not planning to ask your queries of others now or in the future, why is that?
If I unintentionally expressed my dissatisfaction with absence of a reply to my questions from the hosts of this website, I have to apologize. I do not think I have a right to assess them or their motives. Moreover, I have to say that I appreciate replies provided by other readers, even in case they disagree with me.
The were several reasons why I tried to to get answers repeatedly. Mostly it was a new knowledge that changed my view and led me to reformulation of my question, sometimes it was just a reaction to a repeated criticism directed to me.
As regards asking my questions elsewhere: I several times mentioned my previous attempts which I originally made on local level (Czech Republic, Slovakia). This way, I found out that some leading local climate science educators (presenting themselves as climate scientists) genuinely believe that latent heat flux cannot play a role in global average surface temperature regulation. Other local climate scientists that I approached stopped their exchange with me when I asked them if they could correct their colleagues in spreading misleading information to the public.
Two internationally notable climate scientists (of a few that I tried to approach) were, however, willing to reply my questions asked in this respect. One of them even confirmed that there is “lot of misunderstanding” among climate science educators as regards water cycle and latent heat flux role in global climate. I think that it was helpful that one of them is author of a standard physical climatology textbook which, although very briefly, expressly mentions the role of “turbulent fluxes” in global mean surface temperature regulation.
I think that I could now exploit the experience collected herein on Real Climate and try to approach these scientists again, with my yet open questions regarding the knowledge gaps that seem to exist e.g. with respect to relationship between water availability for evaporation and climate sensitivity.
I cannot promise, however, that they will reply, and even less I can promise that I will be able to share their personal views if they will be willing to provide them.
Greetings
Tomáš
Davidsays
Tomáš,
Thank you for enlightening me re your previous attempts at conversing with local and regional climate educators and scientists and sharing that experience here at RC. If that sharing happened this year then I guess I missed it or saw it and subsequently forgot. It sucks to get old ;-) But thank you for taking the time and reiterating above.
I’ve relied on RC as a reference site and of course the hosts’ articles for quite some time. However, I only began to read the comments this year.
GISTEMP has reported for July with an anomaly of +1.21ºC, this a small drop on June’s +1.25ºC (but this only because June was adjusted up from the earlier published +1.21ºC).
And July 2024 becomes the 14th “scorchyisimo!!” month in-a-row, last July being slightly cooler at +1.19ºC. And with August 2023 also with an anomaly of +1.19ºC, a 15th “scorchyisimo!!” month in-a-row could be on the cards. (The daily ERA5 reanalysis at ClimatePulse have been showing the early August anomalies running up a bit.) Previous runs of “scorchyisimo!!” month in-a-row managed seven in 2015/16 and six in 1997/98. NOAA has also posted for July (although the link is proving a bit lazy at present).
For the full calendar year 2024 to end up with a lower average than 2023, the Aug-Dec average anomaly would have to drop below +1.02ºC. In the times before the 2023 “bananas” anomalies, the warmest Aug-Dec were 2015 & 2019 at +0.99ºC.
But perhaps the level of cooling is more the measure of it.
Relative to the Jan-Jul average (+1.28ºC) that would be a drop of 0.26ºC. Past years have seen drops of 0.25ºC (2008), 0.20ºC (1998), 0.16ºC (2016), 0.15ºC (2006 & 2020) & 0.14ºC (2002).
Of relative to the Jan-Apr average (+1.34ºC) that would be a drop of 0.32ºC. Past tears have seen drops of 0.32ºC (2016) & 0.22ºC ( 2006, 2017 & 2020).
But in this post-‘bananas’ climate, pre-2023 years may not be good indicators of what to expect.
Pete bestsays
Where are we regarding accelerating climate change? Still evaluating or is the rate of warming increasing.
Pete, Gavin posted on the apparent acceleration of the GMST trend last April. MA Rodger, a numbers guy for sure, contributed comments. I re-posted Tamino’s announcement on the July thread because I had the same question you do, after Gavin’s conclusion in April (emphasis his):
Or, to put it another way, everybody is (or should be) expecting an acceleration of climate warming (in the absence of dramatic cuts in GHG emissions) (CarbonBrief has a similar analysis), even if we might differ on whether it is yet detectable.
So, I’ve been expecting a showing of statistical detection. My last Statistics course was 40 years ago, so while Tamino’s posts always impress me with their thoroughness, attention to detail, and humility, I don’t try to follow his application of specific procedures. His plots are always crystal-clear, however. If he says
My conclusion is that recent acceleration of global warming isn’t just likely, it’s confirmed.
then I’m inclined to accept that as fact, albeit tentatively and provisionally, per scientific philosophy, culture, and practice. OTOH, I’ll happily defer to people such as MA Rodger, who is more qualified than I. Last month his comment was “I don’t see anything immediately new in the Tamino post.” I’m aware that theory predicts acceleration; it was the statistical confirmation of the prediction that was news to me. But Tamino himself finished his post with accustomed humility:
There is still room for doubt, if you doubt that the adjusted data represent things correctly then the recent apparent acceleration may be just random accident. All told, I find that too unlikely.
I’m left with a tentative, provisional increment of alarm that global warming has, in fact, accelerated, while watching for a consensus of Gavin’s and Tamino’s peers to form, and exhorting my fellow Americans to vote Democratic.
Pete bestsays
El Niño was over in May I believe and now it’s a neutral phase but 2024 is still warmer than 2023 so far. Could be the hottest year – should it be.? 2024 should be slightly cooler than 2023 which was peak El Niño.
It’s a close run thing but El Niño temporarily spikes global temps and then it should fall back slightly but even if it is int falling back as much as expected ?
That’s my angle
Ray Ladburysays
My own analysis supports the nonlinear increase of temperature over time. The past year’s result does influence the trend, but it’s significant even if you only include the past decade and not this past year.
I note however, that if you plot temperature vs. ln[CO2], the trend is still linear. This is not surprising, since the increase in CO2 is nonlinear (quadratic gives an excellent fit.). This suggests to me that we aren’t seen a fundamental change to the physics or feedbacks. [CO2] is still driving the show. However, this is not to say that at least some of the nonlinearity in [CO2] increase could not be the result of natural feedbacks. We know fires, melting permafrost, etc. are increasing, while the increasingly warm oceans are likely not as effective a sink as they once were.
Oh, and for the benefit of Weaktor et al., the R-squared for T vs. ln[CO2] exceeds 0.92.
Yes or no question: Is “global warming” defined as GMST??? Is “climate change”???
If the goal is to educate “the public” and counteract the obfuscation from the usual suspects like the vaporheads, isn’t it time to offer a more disciplined and complete presentation?
Davidsays
Propublica is out with yet another top-drawer piece of reporting, this time concerning training videos being used in furthering preparations towards implementing the various goals outlined in Heritage Foundation’s Project 2025.
One involves the disgusting anti-science, anti-democracy, and anti-humanity approach underpinning their plan for Trump and his incoming team to target all research and government action on climate change and to scrub the subject everywhere in the government.
Time to work on “Mercury Rising,” in my case. But thanks for sharing, and I hope the cocktail was a good one.
Mal Adaptedsays
Wow, that’s pretty arrogant, Sabine. You sound like a couple of long-time RC regulars who are never content just to be right, they have to be the only ones who are! I, for one, am not worried about Project 2025, any more than I was about Agenda 21 in 2016. Both inspired conspiracist ideation, on the left and the right respectively. I personally have no problem with grandiose, aspirational proposals to remake the USA and the world. Talk is cheap, and our constitutional checks and balances have so far prevented outright dictatorship (more about that later). I’m not looking for a total program from decarbonization advocates, of which I’m one: I’ll settle for incremental collective interventions in the energy market, to take more and more of the profit out of selling fossil fuels until nobody’s investing in them any more because carbon-neutral energy is ubiquitous and cheap, whereupon the cumulative cost of global warming will be capped. If the rest of humanity’s impacts on the biosphere continue unabated, at least it will be in a stable climate!
I’m a little more disturbed by Trump’s assurances to Christian conservative supporters that they’ll never have to vote again if they vote for him this November. Sounds like dictatorial ambition to me! It’s infuriating, even if he isn’t actually capable of following through. The Democrats aren’t saints, and have their own historical collaboration with Big Carbon to answer for, but they’re clearly the lesser evil in this election! We’ll never get the government we really want, because our system isn’t designed that way; and whom can we trust to lead a change without making things worse?
As for your contemptuous declarations that the rest of us are all naive dupes of carbon capital: The decades-long investment by fossil fuel producers and investors in propaganda and undue political influence, to thwart collective intervention in their profit streams, is common knowledge on RC. What makes you think you know something the rest of us don’t? You do understand that the IRA of 2022 was the first federal policy enacted to begin decarbonizing the US economy since Jim Hansen’s Congressional appearance in 1998, don’t you? The IRA is hardly going to bankrupt the Koch club by itself, but its symbolic importance is huge IMO. It passed on the slimmest of Democratic majorities. A Republican victory this fall threatens to reverse even that baby step. A Democratic victory offers hope for strengthening and extending our collective decarbonization policy. But politics is the art of the possible. We should all be doing whatever we can to undermine the petro-plutocracy, but we can’t expect to win that war in one fell swoop, because $trillions in annual profits can buy a lot of votes. Casting ours for Harris/Walz is literally the least we can do!
Sabine: “all the Democrats are doing is rearranging the life boats on the Titanic.”
Too dogmatic, IMHO. What Democrats are doing is more like trying to slow down the Titanic before it hits the iceberg, while a loud group of Republican officers and passengers keeps shouting “What iceberg? Full speed ahead!”, and a handful of leftists tries to grab the wheel. Gotta love metaphor. With more moderate Democratic hands on the levers of power, the ship just might make it to shore before it sinks. The passengers won’t ever get back to where they came from, but at least they’ll be alive. Perfect is the enemy of survival!
I respectfully request that you view yourself from our perspective. You’re not the only one thinking hard about this. If what you want is to cap the cost of global warming at the lowest possible total in money and tragedy, well, most of us want that too. We all know who the actual denialists here are when we see them. Let’s reserve our enmity for them.
It is truly hard to imagine denying or actively minimizing [that “trace gas cuts will never be enough because systems are changing for numerous compounding reasons”], due to an artificial fixation on trace gas.
Well, I find it hard to imagine that, too. But apparently you don’t, because you are apparently under the misapprehension that somebody here actually is saying that. That’s not correct, unless I’m deeply mistaken.
What many, including me, have said is that:
1) It is imperative to stop the increase in GMST;
2) That to do that it is imperative to stop the increase in what you persist in calling “trace gas” (GHG) concentrations.*
We have NOT said that this will address all ecological problems. We do NOT oppose conservation of wetlands, old-growth forests, native grasslands, peatlands, or any other ecosystems you might care to name. In fact, quite the contrary.
On the other side of the ledger–and going back to point #2 above–we do say that on present evidence it seems highly unlikely that trying to stop increasing GMST by conserving wetlands is going to be effective. It may be–I would say very definitely IS–desirable on its own terms. We do indeed have an extinction crisis, and it has multiple drivers, not the least of which is straight-up habitat loss. But that case is best made on its own terms–not using the justification of slowing global warming, which is likely quite specious.
(And, be it noted, also thereby muddying the waters as far as messaging the public.)
JCMsays
Thanks McKinney. I agree the most pronounced co-benefit of conservation stewardship from a climate perspective is reduced hydrological and temperature extremes. Across different forums, particularly in person at farm stewardship workshops, I don’t make any mention of GMST. There the most sought after subject is nutrient management and sediment export. However, on these pages, I was told some time ago that the key values of interest to participants are GMST (or GSAT or similar) and global policy recommendations. So, I try to align my contributions with that framework here. Cheers.
Mal Adaptedsays
Thank you, Kevin. You ably represent the climate-science consensus supporters among RC’s commenters, who understand that global warming has multiple, hierarchical causes from ultimate to proximate, arising from the overlapping knowledge domains of physical science, ecology and evolution, economics, anthropology, psychology, sociology, political science, and above all, human history. We focus on the anthropogenic physical causes, primarily but not limited to “trace gases”, because that’s the announced topic of this blog, and it’s where RC’s authors and many regular commenters have some training and expertise! Many of us have definite ideas about the ultimate causes of all the ancient insults and injustices humans have inflicted on the biosphere and each other. Many of us also have definite ideas regarding What Is to Be Done about it all. We do occasionally discuss those ideas here, but tend to shy away from them because they are highly subjective, and tend to provoke weeks of pointless off-topic drama! In addition, few of us have enough exposure to everything that’s known about the diverse causes of global warming and the uniquely contingent history thereof, to expose ourselves to ridicule by other RC regulars: a sort of informal peer review!
OTOH, the warrant for RC’s monthly UV thread is broad. JCM, and Sabine (surname unknown) represent people who view the long history of our unsustainable behavior toward the earth and each other from a passionately humanistic perspective. Both appear incompletely informed on certain scientific aspects of our global predicament, but their passion is the underlying message in their comments. The heck with scientific reticence and the principle of least drama! They have strong moral opinions about the way people ought to behave “sustainably” by their subjective definitions. Everyone is an expert on their personal morality. However, collective action to reduce our “environmental” impacts as a population is within the domains of the behavioral sciences, about which I presume few of us are experts. Both JCM and several-comment Sabine claim to know crucial facts we don’t, and seem angry that we don’t explicitly recognize their superior knowledge and endorse their prescriptive solutions, forsaking much we’ve been at great pains to learn. The pair are almost certainly wrong about the efficacy of their preferred remedies, but at least they’re confident!
Yet neither JCM nor surly Sabine are climate-change deniers, unlike so many of the antagonistic pseudo-skeptics who show up here. It’s a novel experience for me, at least. I’ve actually learned a few things, from JCM especially, despite his rejection of both the CO2 greenhouse effect and the principle of least drama. Both of them are mitigation alarmists, although not obvious lukewarmers; I for one find their mitigation proposals rather alarming, however. I’m reasonably confident neither has the wherewithal to implement their programs, because they don’t appear to recognize that “Politics is the art of the possible, the attainable — the art of the next best” (Otto von Bismarck), or that perfect is the enemy of better-than-it-is-now! It’s uncertain that incremental, targeted collective action to take the profit out of selling fossil fuels can fully decarbonize the global economy, in the time we have left for collective action on a scale larger than a fortified town; nonetheless, I have no doubt that global heat content will rise until we accomplish it. Nor am I happy about the environmental impacts of producing carbon-neutral energy for 8 billion people. But I’m convinced that without capping the 300-year anthropogenic upward trend of trace gases in the atmosphere, no other collective action to mitigate multiple tragedies of the commons can succeed for long, and will eventually be impossible. Of course Democrats aren’t pure of heart, for “Out of the crooked timber of humanity, no straight thing was ever made”(Immanuel Kant). They are, however, clearly the lesser evil here and now!
But here we have people who should know better participating in rhetorical word games with the last desperate vaporhead denialist types, the pages filled with the same nonsense repeated over and over.
And in the real world, real people are accumulating their own data… breathing the smoke from fires, and drowning in downpours, and succumbing to excess heat. But I’m sure they really care about the statistical nuances of GMST, a variable which has no effect on anything.
Time to move on.
Barton Paul Levensonsays
z: But I’m sure they really care about the statistical nuances of GMST, a variable which has no effect on anything.
BPL: The variable “your weight” has no effect on anything, either, but the medical condition it suggests can have profound meaning. Don’t confuse the measurement with what it’s measuring.
zebrasays
BPL
“The variable “your weight” has no effect on anything, either, but the medical condition it suggests can have profound meaning. ”
???
No, not even close as an analogy, and incorrect as well, physics-wise.
“Don’t confuse the measurement with what it’s measuring.”
That’s the point of what I said to Kevin!
And I would wager 98% of the public that accepts the concept of climate change is doing exactly that, because of sloppy communication even by the professionals.
The real point is illustrated by the reference I gave… did you at least scan it?
GMST has obviously been useful as a proxy for increasing overall system energy, but now we can determine that directly, as well as for sub-systems. Seems to me the “climate blog by climate scientists” should, as I said, be moving on.
jgnfldsays
Bit of a nit, but needs clarity given all the stats BS we see here from some: While things can get rather more complex with such techniques as path and mediating variable analysis (of old), various autocorrelations from feedbacks/feedforwards, machine learning, etc of today, one thing should be pretty clear: Observations of final dependent measures actually should either (1) NOT have effects on the input variables or (2) HAVE measurable and partitionable feedback parameters.
zebrasays
“It is imperative to stop the increase in GMST.”
No Kevin, it isn’t. It is imperative to stop the increase in climate system energy, as quickly as possible. That means achieving a balance in incoming and outgoing radiation.
But I guess if you said it that way, you couldn’t keep these inane, repetitive, pretend-science discussions going, on and on and on.
Speaking of inane, repetitive, pretend-science… spiced with inane, repetitive, and highly pretentious Language Cop nonsense…
Mal Adaptedsays
Huh. Looks like the comment of surly Sabine’s I responded to has been deleted.
alansays
Yes, and quite annoying for readers (like me) who have to go back and forth trying to figure out WTF you are responding to.
Moderators: for the love of God, if you want to censor/delete posts, fine; do so BEFORE YOU ALLOW THEM TO BE POSTED. Thank you.
Susan Andersonsays
@alan – I can’t help with the Sabine, though you can get a flavor from her (his?) other comments, which on the whole are a waste of time and energy. However, here’s the ProPublica, and you can see that a number of us find it one of the best research/public service information resources around. I know the outrage factor seems over the top, but there’s an awful lot to be outraged about, and their work is reliable. Main site -> https://www.propublica.org/
Item in question: https://www.propublica.org/article/inside-project-2025-secret-training-videos-trump-election
I put myself on their mailing list long ago, have to admit there’s so much ‘bad’ news there I had to go back to my inbox to find the relevant item.
As for strictures on moderation, my impression is that they’re overworked and have day jobs, so in general not much moderation occurs. If I were to guess, the community’s outraged reaction and perhaps some rare over the top disinformation caused this unusual post facto deletion.
As ‘for the love of god’ – note that this comment section is full of good, bad, and indifferent material, and endless arguments therefrom, so I wouldn’t invest my emotional (or spiritual) well being in knowing who’s talking about what.
Mal Adaptedsays
Susan:
As ‘for the love of god’ – note that this comment section is full of good, bad, and indifferent material, and endless arguments therefrom, so I wouldn’t invest my emotional (or spiritual) well being in knowing who’s talking about what.
Nice. With apologies to everyone including Gordon Lightfoot, I can’t resist:
Does anyone know where the love of God goes
When the [trolls] turn the minutes to hours?
The insult-filled response from Sabine contains multitudes in the matter of contradictions, peculiar and inconsistent. Though S claims we don’t read, she appears not to have read the ProPublica article, which is much shorter than Project 2025’s many pages (an earlier version was 887 pp and other lengths are cited).
As long as I’m here, another superb Jeff Masters review: The U.S. is nowhere near ready for climate change: Despite recent investments in adaptation, the U.S. remains woefully unprepared for the coming extreme storms and floods. – https://yaleclimateconnections.org/2024/06/the-u-s-is-nowhere-near-ready-for-climate-change/ … One can acknowledge we’re not doing enough without making things worse by making an an excuse to replace those who are trying with those eager to deceive, cheat, profit, and blame victims.
Yes, the current Democratic administration has terrible stats on actual cutbacks of fossil fuel extraction and use. Their compromises are driven by the realities of democracy in action where doing the least bad is all that’s available. That is no excuse for electing the worst. It should be a driving force to get rid of all corrupt liars in our legislatures and courts, and to get a majority large enough to reform SCOTUS.
Spewing bile about our hosts here at RC and those trying to do what they can is both contemptible and wasteful.
Sabine would do better to absorb Jane Mayer’s Dark Money (also the earlier Chris Mooney’s Republican War on Science). Rachel Maddow’s Blowout is superb on the influence games of the extraction industry. Anything from ProPublica is likely to be well researched and reliable, as is Inside Climate News.
I have a feeling that the content published by Sabine and even more her style remarkably resemble the person who was very active on this forum under a nick “Ned Kelly” and then suddenly disappeared.
Best regards
Tomáš Kalisz
Susan Andersonsays
TK: No. NK’s style and content were different. There are plenty of other bores and cranks in a variety of flavors here (and, as is sometimes noted, arguing here is a substitute for doing something real in most cases), but I’m guessing our collective complaints about NK’s massive body of work overwhelming any reasonable back and forth here were heeded.
K McK (and others): The relevant Sabine comment does appear to have been removed. That’s interesting. Perhaps some more active removal of some of the more extreme provocations happened. [I checked both crank shaft and bore hole and they’re not there. I guess there comes a time when timewasting is simply not worth it any more.]
After all, we do have community guidelines and if we don’t follow ’em, it’s not surprising if there are consequences. AFAICT it’s not about the links, it’s about the obnoxity.
Radge Haverssays
Thank you, SA.
Looks like there’s yet another troll sock puppet on the loose.
Actually, I find that the Borehole seems now to exist only in some archives, while I found no trace of the Crankshaft at all. Unless, of course, I stopped looking too soon, which is not impossible.
Nigeljsays
Kevin. Go to the list of archvives by category. The bore hole and crank shaft are right at the end of the list. If you click on them and get a largely blank page, click on the title bore hole or crank shaft on the blank page a second time and the comments appear.
Nothing in there by Sabine. Her comment just seemed to get deleted.
Nigel, thanks. I can find the categories where you describe them, but click as I might, no actual post appears. I did get to the Bore Hole via a search result, and saw some items from as recently as last year, but nothing since.
But really, no matter AFAIAC. I was pursuing it for mere idle curiosity.
Mal Adaptedsays
I thought I was the only one puzzled by the missing provocation from Sabine (the one who isn’t Dr. Hossenfelder). Yeah, David’s mention of ProPublica set her off. Her truculent reaction was here for a couple of days, but no longer appears, leaving our subsequent replies without a challenge to reply to! The removal was presumably intentional, as many (all?) of her previous comments are still in place. They evince her growing resentment, but none were quite as unhinged as the missing one. I expect we’ll never know, however.
Both the Borehole and the Crankshaft are now just empty bit buckets, AFAICT. Once again, my sympathies are with the moderators.
Silvia Leahu-Aluassays
Yes, Susan, I completely agree. There should be no hesitation in electing the social-democrats/liberals/center/progressives, a.k.a.the D party, as opposed to the reactionaries. The upcoming Democratic administration will be more progressive, as this is where their base and the majority of voters are. I am convinced that we will see more of the Green New Deal implemented.
Hopefully, voters will decide on policy and the politics of delivery for the common good, not of theatrics, no matter how much the media, in all forms, stay trapped in the latter, with few exceptions. ProPublica is one exceptional exception; “Investigative Journalism in the Public Interest”
alansays
I want to read the “insult-filled response from Sabine” because I want to know what the hell is going on here, and what Susan Anderson is replying to.
For example, Anderson writes that Sabine “appears not to have read the ProPublica article”. WHAT ProPublica article? One cited by Sabine? How can I find it? How can I read Sabine’s post?
This *post hoc* deletion (after the fact deletion of posts; pun not intended) is extremely annoying.
Radge Haverssays
This is still a moderated site, even though the hosts are busy with other things. Cut them some slack.
FWIW, it appears that, in order to get a comment deleted here, you have to troll pretty hard and succeed in being disruptive. Add to that that Sabine was likely a sock puppet of a previous troll who had already wasted an inordinate amount of space and time here being a jerk for the sake of being a jerk.
IMO there’s no point giving someone like that oxygen, and frankly you’re not missing anything from what’s been deleted– especially since there are more interesting things here to focus on.
If you’re curious, note that although the borehole and crankshaft seem to have been relegated to inactive archives, you can still check them out to get a sense of the kind of stuff that has historically been considered too ridiculous for adults to waste time on.
Mal Adaptedsays
This is why it’s wise to lurk on a blog for a time before putting one’s 2¢ in. If it’s any consolation, this is the first time I can recall that happening without explanation on this blog in years, if ever. The rare removals of comments have always been preceded by warnings. Like multiple otters (but not sea lions), I reacted negatively to singly-named Sabine’s attack on ProPublica and our collective credulity. Her comment was childishly offensive [Hey, I resemble that remark! MA], but I didn’t think it was that bad, at worst nothing legally actionable. We’ve all seen worse here from time to time, and sometimes have managed to expel certain intolerable irritants decisively, but none of us but the moderators have the ability to delete comments! AFAICT that’s the only one of her multiple comments that’s no longer accessible. I did notice that all comments by “Bok” are missing, from last month’s UV thread as well as this one. Again, AFAICT they weren’t offensive at all. The puzzle waxes!
I’m baffled too, but I’m pretty sure if Gavin and colleagues had anything to do with it, they’d tell us. If not, they’ve all got better things to do anyway. Lurk and learn.
Sabinesays
@MA Rodger says
12 Aug 2024 at 8:07 AM
I am not that Sabine. A typo may have sent you astray. I read your comment, and am none the wiser. I recommend you review her commentary more closely:
eg
“So whom can you trust? Trust no one. What you can trust for the most
part is: data, maths, and logic. At least in the physical sciences,
and I count climate science as physics, it’s incredibly rare for data to be wrong
or fraudulent, and for that to remain undiscovered. It happens, but it’s rare.
It’s likewise rare that maths or statistical analysis is just wrong, and for that not to be
criticised or corrected. Indeed, the problem in the foundations of physis is not that the data
or maths is wrong, it’s that they have no data, and the maths isn’t about anything in particular.
And finally, there’s logic. Logic is your friend. Trust arguments, not people. ”
imo too many people (scientists) are focusing on minutia, like monthly and yearly data and anomalies and statistical graphs, when the real science about global warming, global temperatures, massive changes in the climate and SLR are actually about DEEP TIME on a planetary scale. And too much data is missing and not being considered logically.
So it’s not really about acceleration over a short period of time, or net zero by 2050 or anything like that, or this months anomalies or this years Global Mean Surface Temperatures, or who wins the US election in November.
No one (sane) has said SLR will increase by +5 metres by 2100. Or 2025 to 2125. Or 200 to 2150. 2100 is NOT Deep Time either. Nor is a century. The current warming rate is multiple times faster than any of the last warming of post glacial periods over millennia. Hansen is right iow, or at least more right because he uses better data and logic.
Watch Sabine’s video again, I believe you missed all her key points of what really matters re the Science and Scientists and why none of them should be trusted or believed. See quote above again. Good luck.
Sabine,
Regarding the video of your namesake, I clearly remember the quote you provide & am not sure what a would be gained if I “review her commentary more closely.” And if I did miss “all her key points” (which would be a surprise) perhaps you could set them out. What I do struggle-with is what you mean by “DEEP TIME on a planetary scale” and I do not understand what it is you mean specifically by “too much data is missing and not being considered logically.”
This “deep time” appears to concern periods far longer than a century (which is too-long a period for action to cut emissions to Net Zero) although such a timescale is applicable for consideration of SLR which takes eventually millenia to run its course.
The idea of +5m SLR by 2100 should not be seen as entirely insane without some initial consideration and indeed has been projected in published papers. (So not “no one” although it is not quite the same as them saying “SLR will increase by +5 metres by 2100”).
Specific to ‘+5m SLR by 2100’:-
A decade-plus ago, the various SLR analyses were always calculating a limit to 2100 SLR at roughly 1m.
But then an outlier appeared with a 2100 5m projection. Hansen (2007) ‘Scientific reticence and sea level rise’
Sudden SLR rise has been seen in paleoclimate studies (Meltwater Pulse 1a saw multi-metre SLR per century or multi-centimetre SLR/yr, this in a world with a lot more ice) and that leads to the worry that Antarctica could suddenly begin quickly shedding ice with just modest levels of AGW. But this proposed idea of decadal doubling-times continuing for a century appears unsustainable. The 1mm/yr SLR polar ice component of SLR would become 512mm/yr by 2100 with a 10yr doubling-time. The energy requirements to melt 180,000 cu km of ice per year would be 100% of the forcing from a doubling of CO2. So, while not an entirely-insane energy requirement, this energy does somehow need directing to the ice (or the ice to it).
A partial exploration of such a process was eventually set out in Hansen et al (2016) ‘Ice melt, sea level rise and superstorms’. However it only assumed various doublings (including annual multi-decimetre SLR) so as to then model the climatic implications. What is missing is any substantial basis for annual multi-decimetre SLR. A multi-metre SLR over millenia resulting from a +2ºC warming is not contraversial. (IPCC AR5 Fig13.14 shows an equilibrium SLR of +4.2m/ºC plus +5m from Greenland melting down which is the expected equilibrium result for AGW less than +2ºC.) Hansen et al (2016) admits the doubling profile cannot be properly inferred from recent data and thus the idea that such ice melt/calving could be achieved is solely supported (I consider mistakenly) by Pollard et al (2015) which only shows +30mm/yr SLR resulting from Antarctic melt/calving (from +2ºC SST = roughly +4ºC SAT) which is nowhere near annual multi-decimetre SLR. Another reference (Hansen et al 1984) appears to be suggesting it is temperature rise which is unstable due to interactng feedbacks, and that this in turn drives massive SLR. But that is a whole different argument.
Tomáš Kaliszsays
A question in Re to MA Rodger, 15 Aug 2024 at 1:14 PM,
It appears that the crucial point that may be decisive for the assessment if the rapid multi-metre sea level rise till the end of this century may or may not be physically possible are the following questions:
1) Is there a sufficient energy source (or, perhaps, a sufficiernt energy reserve already stored in the system – e.g. in form of heat already accumulated in ocean) that could enable the considered melting of the necessary amount of ice?
2) Is there a mechanism how this amount of energy could be distributed quickly enough to the available ice to enable the assumed ice melting?
From your reference to the Meltwater Pulse 1a, it can be construed that under different circumstances (lower greenhouse effect, different insolation distribution over the globe, higher amount of available ice), a such rapid ice melting already happened.
Are there some studies that clarified the mechanisms which enabled this impressive melting / SLR speed during the Meltwater Pulse 1a? If so, I think their approach could provide a clue to the question if a such rapid melting is possible nowadays as well. If not, then I think that focusing scientific effort in this direction might be quite desirable.
This +5m SLR by 2100 idea has usually been attached to Hansen’s notion of doubling the net polar ice-melt multiple times. Thus the present-day +1mm/year SLR from polar-ice melt could grow to become multi-decimetres/yr by 2100 – upward of 300mm/yr to approach that +5m SLR by 2100. So that would be [ 300 x 361 =] 108.300 cu km of ice per year requiring 33Zj to melt. Globally, that is 2W/m^2, equal to half the global forcing of double CO2.
You asked “Is there a sufficient energy source?” There’s masses of energy flying round planet Earth. For instance, there is the 160Wm^-2 absorbed by the surface from the sun. But such energy needs to be diverted from where it goes today and applied to melting ice. One of the ways of finding 33Zj/yr is by cooling the planet and increasing the Earth’s Energy Imbalance. This is what was modelled by Hansen et al (2016) when they impose the 5-yr, 10-yr and 20-yr doubling times to ice-melt and showed a 3.5ºC drop in global temperature and a +2.5Wm^-2 increase in the EEI. But that was modelling the effect not the cause.
Hansen et al say, “A sea level rise of 5 m in a century is about the most extreme in the paleo-record (Fairbanks, 1989; Deschamps et al., 2012), but the assumed 21st century climate forcing is also more rapidly growing than any known natural forcing.”
Those “most extreme” SLR in the references work out as 40mm/yr (Fairbank’s “maximum rates of 14,000 km^2/yr”) and a meaty 180mm/yr (18m in a century) is described as “extreme but possible” by Deschamps et al but also with 50mm/yr presented supported by other evidence. And these SLR rates being measures of Melt Water Pulse 1A, the relative level of forcing back 14kya is surely immaterial.
In the absence of 14,000km^2 (or multiples thereof) waiting to discharge into the oceans, I would suggest the mechanism we need to fear is a truly massive discharge of icebergs which can then float off to melt at warmer latitudes. However I don’t so far see any work projecting such a doomsday scenario.
Of course, the equilibrium SLR from AGW is already multi-metre (over millennia) so reducing GHG levels will be required if we are not to drown a significant portion of human real estate.
mentions breaking giant ice dams and quick release of huge amounts of melt water accumulated over centuries in giant lakes behind these dams into the ocean as the mechanism of the very rapid Meltwater Pulse 1a.
This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR. I would appreciate your kind comment anyway.
Apologies for the overlooked typo in your name.
Piotrsays
Tomas Kalisz – “ Dear MA Rodger, Piotr, mentions breaking giant ice dams and quick release of huge amounts of melt water accumulated over centuries in giant lakes behind these dams into the ocean as the mechanism of the very rapid Meltwater Pulse 1a.
This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.
Aga-baga? Don’t you understand ANYTHING your read, Tomas??? My argument argues the very OPPOSITE to what you claim it does! Specifically:
I said that multimeter SLR in the past, are not a good model for the potential future SLR rates – because they were caused by the specific conditions that are ABSENT today: by the collapse of ice dams, which released the meltwater accumulated on land over centuries. Today, NEITHER Greenland nor Antarctica has such giant lakes, waiting to break through the ice and add rapidly to the SLR. This makes the likelihood of “the rapid multi-metre SLR” in the near future LESS, NOT “more” likely, as you claim.
Don’t you have some remedial reading courses in Czechia?
I accept your objection, although I think it rather fits my writing skills than my reading.
In my original sentence
“the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR” ,
I strived to express my satisfaction that the present situation significantly differs from the situation that led to the very rapid multi-metre sea level rise in the intergalcial, and that in this view, the threat of a such rapid multi-metre SLR till the end of this century may be in fact not as bad / as serious as some regular Real Climate readers, e.g. Geoff Miell, are afraid.
I am sorry for drafting my sentence the way that confused you.
Greetings
Tomáš
Piotrsays
TK: “I accept your objection, although I think it rather fits my writing skills than my reading”
No, your writing, even though pretentious. meandering, and avoiding answering the direct questions is one thing – the fact you often COMPLETELY misrepresent post you read , and you “answer” is rarely if ever on a subject – indicates your inability to read / comprehend the texts you comment. In the above case – after my cautioning against extrapolation past SLR onto a very different future – you “understood” as =my supporting such extrapolation (“ suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.
In other words – you could NOT HAVE MISUNDERSTOOD my text more. Hence:
“Don’t you have some remedial reading courses in Czechia?“
I have explained that I understood your post exactly as you meant it.
If you are not a telepat, please be so kind and desist from asserting what other people read or misread.
Best regards
Tomáš
Piotrsays
Re: Tomas Kalisz Au.25:
No, Mr. Kalisz, I does not take a “ telepat” to be able to read what you wrote and notice that IN YOUR WRITING you completely misrepresent my argument. As I wrote it in the post to which you reply:
===
P, Aug. 23 – “I cautioned against extrapolation past SLR onto a very different future
– you present it as … my supporting such extrapolation (“suggest that the situation might be more favourable now [for] the rapid multi-metre SLR“)
==
Then, I gave you the benefit of the doubt – that you didn’t understand my argument. But since NOW you insist that you “ understood your post exactly as [I] meant it“, then it means that you KNOWINGLY mispresented my arguments as OPPOSITE to what you KNEW they were.
In other words, that you, Tomas Kalisz, are a LIAR who DELIBERATELY misrepresents other people arguments.
And no, your pathetic attempts at legalese (“desist from asserting“) won’t stop me for calling you what you’ve proven with your posts to be.
“This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.”
Are you sure that your transcription of my sentence,
“This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
which you take as a basis for your objections, is equivalent to my original?
I have a feeling that, for example, the word “threat” that in my opinion plays relatively important role in my sentence, got somehow lost in your translation :-)
Greetings
Tomáš
Piotrsays
Kalisz Aug. 27: Are you sure that your transcription of my sentence,
– “This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.” [as]
– “This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
which you take as a basis for your objections, is equivalent to my original?
Yes, I am sure – “at least as regards the discussed threat” is just a chaff that changes nothing. As attested by the fact – that my response:
====
“Aga-baga? Don’t you understand ANYTHING your read, Tomas??? My argument argues the very OPPOSITE to what you claim it does! Specifically: I said that multimeter SLR in the past, are not a good model for the potential future SLR rates – because they were caused by the specific conditions that are ABSENT today”
===
applies EQUALLY WELL to your “original” as to the cleaned-up summary of it by me.
Your English is much better than mine, so you also have to know better if my sentence and your transcript are equivalent or not.
Unfortunately, I have a bitter feeling that when you fight a perceived enemy, you are, with a clear consciousness, able to assert that sentences “Milost, nelze popravit.” and “Milost nelze, popravit.” are equivalent too, because the comma is just a chaff and changes nothing…
Greetings
Tomáš
Piotrsays
Re Tomas Kalisz Aug.29.
Dishonest analogy – in your example, the change in the position of a comma changed everything, In my post – my replacing the highlighted words with “for”:
– “This seems to indeed suggest that the situation might be more favourable now [ at least as regards the discussed threat of ] [for] the rapid multi-metre SLR.”
changes NOTHING, other than making your (false) claim it less meandering. Hence your insinuation of my misrepresenting your words is, as usually with your insinuations, baseless.
And your littering your sentences with words that contribute nothing to your argument – is not a problem of your English, but of clarity of your thinking/writing. I’d bet your Czech is as intellectually undisciplined, pretentious, and lacking self-awareness as is your English.
You can tell a lot about people by the language they use.
My Czech example was only to explain how I perceive your arguments – I doubt that anyone else read it except you.
I’m happy to admit that my originall sentence was ambiguous, but I’m still reluctant to believe your claim that it meant the exact opposite of what you wrote in your post (and what I intended to confirm / to agree with).
Anyway, I think that we can and should close this exchange now.
Greetings
Tomáš
Piotrsays
Tomas Kalisz Aug. 30 – I’m happy to admit that my originall sentence was ambiguous
It wasn’t ambiguous – it was poorly written, loaded with chaff that adds NOTHING to your point, thus a product of undisciplined, sloppy, mind. But we already know it about you – so it that wasn’t my objection – I objected to your insinuation that my quote distorted the meaning of your words:
>> original – “This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.”
>> my shortened version: – “This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
I asked you to put your money where your mouth is – to demonstrate HOW the omission of the highlighted words – significantly CHANGED the point you were making. You didn’t, nor did you apologize for the insinuation you were not able to prove.
Until you honestly own up for your actions – I don’t see the point of answering your subsequent questions as if nothing has happened.
If your transcription of my sentence is correct, I apologize that I have not believed you that my sentence has in fact an opposite meaning as I thought and that I suspected you from a deliberate manipulation with my words.
Greetings
Tomáš
JCMsays
To Tomas,
Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”.
Obviously this directly opposes the bizarre distortions on display by respondents. Global landscape hydrology is a huge known information gap which is increasingly recognized. When detractors say things like “both of you REFUSE to acknowledge the conclusions” it doesn’t make any sense at all. They have it totally backwards. The so-called answers are completely fabricated and unsupported. Additionally, regressing back into arguments such as “given how small human impact is compared to the volume of global water cycle, and how short the residence time of water vapour in the atm is (~ week)” suggests detractors have not yet understood the idea at all. How is that even possible?
I recommend to avoid getting sucked into an endless vortex of nonsense if at all possible. Repeatedly pointing out the same falsehoods over and over again is usless. It should be time to move forward as Lague was initially introduced simply on the request to supply a quantitative analysis why Piotr and co were totally wrong to imagine that catchment stability is inversely related to climate stability. Ongoing uninformed and butchered attempts to rationalize a fixed ideological opposition to terrestrial biogeophysical process considerations to realclimate observables is misguided
For clarity, the suggestion that support for the values of landscape appreciation and research automatically means opposition to trace gas abatement is totally false. As previously mentioned, even Johan Rockström @ Potsdam is saying trace gas cuts will never be enough because systems are changing for numerous compounding reasons. This is so simple to understand and non-threatening. It is truly hard to imagine denying or actively minimizing this due to an artificial fixation on trace gas.
For instance, it is increasingly recognized that the significant declines in the resilience of systems like the Amazon are not primarily caused by trace gases: ‘Observation-inferred resilience loss of the Amazon rainforest’ (https://esd.copernicus.org/articles/15/913/2024/) states, ‘the results presented here suggest that [GHG], as a major historical and future forcing in models, plays a minor role in the observed rapid decline in rainforest extent. Mitigation strategies to limit future rainforest loss could therefore be most effective when focusing on other, human-induced stress factors.’
Can you believe it? Recent complex models in July 2024 have re-discovered that stopping direct ecological destruction is an effective way to prevent ecological destruction. The recent defacto hypothesis that dramatic changes should be abated exclusively with trace gas abatement is misconceived.
There are other references as well: ‘Agricultural expansion dominates climate changes in southeastern Amazonia: the overlooked non-GHG forcing’ (Environ. Res. Lett., 10, 104015, https://doi.org/10.1088/1748-9326/10/10/104015).
The literature has long acknowledged what is obvious to many: trace gas reduction is essential for achieving stability, but it alone will not stop the change. Lague’s work demonstrates that the CESM can produce a global response from terrestrial change alone. This is encouraging for the value of ESM-style models and is especially exciting given the disproportionate emphasis placed on global-scale computational analysis for globally significant policy advice.
The message is simple using current-generation models: climates will change with major and minor trace gas emission, and they will change even more with direct biogeophysical destruction. This is so simple to understand.
I suspect that the rigid opposition might be a collateral effect of misinterpretations and an inability to appropriately contextualize teachings like Genevieve Guenther’s ‘The Language of Climate Politics – Fossil Fuel Propaganda and How to Fight It’ or Mann’s ‘The New Climate War.’ I doubt these authors intended for uninformed extremists to take up this fight in the way some are doing. Frankly, actively opposing landscape stewardship is just plain foolish. Alternatively, perhaps these critics are innocent victims in the crossfire of a fight they don’t fully understand, somewhat unaware of their surroundings. It’s the only way I can make sense of it. I’d appreciate any insights you might have on what’s going on here.
I’m currently using WiFi at a gathering on a colleague’s luxurious ranch on Devil’s Gulch Road in upland Colorado. I’ve discussed examples of these interactions and many are aghast. The sense is that amateur GHG enthusiasts and phony-environmentalists are losing their way.
Sabinesays
to JCM
Kudos!
It’s unfortunate the phoneys and unhinged extremists are everywhere.
They are on all sides of the global warming ‘argument’.
Sabinesays
to JCM
I think you are an excellent communicator and writer. I’d recommend you create a Substack space or similar and share these kinds of issues more broadly. There are many good publishers on the topic on substack already who may help to spread your information. And getting an X twitter account and the alt bluesocial account (where some climate scientists are emigrating) to promote your new articles or data could be useful and effective for you.
Your quality insights, clear communication and knowledge are really wasted here on RC. It truly is an inactive backwater and very much a broken record of rhetoric with a very narrow (myopic) focus and troll-like behaviours from the resident groupies.
imho you deserve much better
JCMsays
thanks Sabine. I must admit however, that writing/publishing and academic-style pursuit are not my primary interests. Additionally, I’ll leave social media banter to the cyber pros as I’m not familiar with the most effective tactics. My interests are specifically in applied science, practical implementation, and engaging with communities. Personally I find this to be much more fulfilling.
Piotrsays
JCM to his Robin, July 13:
“ To Tomas,
Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. Obviously this directly opposes the bizarre distortions on display by respondents.
The key word here: “extreme”, as in the difference between all non-iced land being a desert and all non-iced land being a swamp – even for such a EXTREME difference (all desert – all swamp), the global T increased only by 8K. The real Earth does not undergo such extreme swings – consequently – the difference in global T for LESS EXTREME cases (“low – high resistance to evaporation”) is about … 1K.
Furthermore – humans can affect only a fraction of that 1K – since human CHANGES to fluxes of H2O are tiny compared to the natural fluxes, and the residence time of water vapour in the atmosphere is measured in DAYS, as opposed to GHGs – where human emissions are much larger compared to the natural fluxes, and the residence time of human perturbation of GHGs is measured in DECADES ,not DAYS.
As a result of these two factors – the current global concentration of CO2 is about 50% above the preindustrial, CH4 200% above preindustrial, while water vapour can be affected by humans in any appreciable way only through warming by GHGs via Clapeyron Clausius equation. Therefore, if you want to reduce warming caused by reduced clouds – you do it by reducing the temperature by reduction of GHGs concentrations. Water cycle is a feedback, not a driver, and as such it amplifies the effects of our action or inaction on GHGs.
To quote you: “Obviously this directly opposes the bizarre distortions on display by respondents.” Specifically:
– respondent JCM: calls the effects of human (direct) changes to evaporation on global T – “mindboggling” and blames world desertification and ecosystems destruction on … science’s “artificial fixation on trace gas”
“ It is truly hard to imagine denying or actively minimizing this due to an artificial fixation on trace gas” (c) JCM
– respondent Kalisz first calculates how much water we’d need to evaporate to cancel out the radiative forcing of ALL GHG gases, then inspired by JCM’s reading of Lague et al. – formulates a “modest proposal” of increasing the global desalination … at least 1000-FOLD, and spreading the produced water over 5mln km2 of Sahara, with the hope that after 100s of years – the scheme may approach 0.3K cooling.
(Conveniently neglects the warming from massive GHG emissions of constructing and running such a scheme for 100s of years)
JCM: “ Piotr and co were totally wrong to imagine that catchment stability is inversely related to climate stability.”
The Piotr you speak of must be living in your brain, JCM, The _real_ Piotr didn’t “imagine” anything of the sort -my argument does not need any relationship, inverse or not, between catchment stability and climate stability, In fact, the word “catchment” DOES NOT APPEAR in any of my posts on the subject. Nor the word “catchment” exists in your source, Lague et al (2023).
I’d suggest less discussion of the figments of your imagination – and more addressing the falsifiable replies of your opponents to your claims. Like those above, and in the many posts before this.
It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Water vapour concentration in atmosphere is basically independent from water cycle intensity. Residence time of water vapour in atmosphere is a variable that has an extreme broad range,.. just a few remarks that show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.
Best regards
Tomáš
Piotrsays
Tomas Kalisz Aug.14: It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
That’s the problem: your “understanding” ;-) Hint: nobody argued that Lague et al. didn’t use constant GHGs conc.. (Excluding the effect of GHGs was to JCM conflating
the direct effects of evaporation with the effects of GHGs)
TK: “ I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Lague’s comparing an EXTREME and HYPOTHETICAL case of all land covered with deserts, with an EXTEREME and HYPOTHETICAL case of all land being a swamp, SAYS NOTHING about the magnitude of the HUMAN effect on global T via human changes in global evaporation.
So who of us two “ sounds like he has not read Lague 2023 at all >, and has the <b> hutzpah to lecture others based on his own ignorance (inability to understand what he reads) and his intellectual dishonesty (ignoring tens (?) of post where I have already explained to you where your misrepresentation of Lague’s paper lies) ?
TK Residence time of water vapour in atmosphere is a variable that has an extreme broad range
Irrelevant to the discussion at hand: all your “ extreme broad range variability ” gets INTERGATED over the AGW time- (“decades”) and space- (“global”) scales. And when you integrate – the transient/local fluctuations are AVERAGED OUT and therefore of no further consequence. The best example are the results of your Lague et al 2023 – who integrated all those “extreme” local differences to produce a SINGLE average value for all land and another SINGLE average value for all oceans. Which brings us to the reason why we talk about you
And in both cases – these numbers are in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs.
Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
Thus your and JCM narrative trying to minimize the importance of GHGs to AGW, and
trying to dissuade the world from getting off the fossil fuels by implying that we can counter GHGs effects with evaporation geoengineering schemes – remains a denier’s wet dream.
“[opponents] remarks show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.”
and yet you have commented incessantly on Lague et al – even though you the very opposite of “a climate science professional” – you have commented on Lague’s paper in dozens of threads, and used them as a support for your claims – even though have not taken any climate courses, didn’t bother to read any climate textbooks, and even few months ago didn’t understand the differences between fluxes and reservoir size. “ Do as I tell you not as I do”?
Piotrsays
** Please ignore the previous version that went off before the final edit.- Piotr
Tomas Kalisz Aug.14: It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
That’s the problem: your “understanding” ;-) Hint: nobody argued that Lague et al. didn’t use constant GHGs conc.. (Excluding the effect of GHGs was addressed to JCM who has conflated the direct effects of evaporation with the effects of GHGs)
TK: “ I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Lague’s compared an EXTREME and HYPOTHETICAL case of all land covered with deserts, with an EXTEREME and HYPOTHETICAL case of all land being a swamp. This SAYS NOTHING about the magnitude of the HUMAN effect on global T via human changes in global evaporation.
So who of us two: “ sounds like he has not read Lague 2023 at all ?
And who has the hutzpah to lecture others based on his own ignorance (inability to understand what he reads) and his intellectual dishonesty (ignoring tens (?) of posts that has shown your misrepresentation of Lague’s paper) ?
TK Residence time of water vapour in atmosphere is a variable that has an extreme broad range
Irrelevant to the discussion at hand: all your “ extreme broad range variability ” gets INTERGATED over the AGW time- (“decades”) and space- (“global”) scales. And when you integrate – the transient/local fluctuations are AVERAGED OUT and, therefore, of no further consequence. An you have already seen it in your own source: Lague et al 2023 integrated all those “extreme” local differences to produce a SINGLE average value for all land and another SINGLE average value for all oceans.
And in both cases – these numbers are in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs. Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
Thus your and JCM narrative trying to minimize the importance of GHGs to AGW, and
trying to dissuade the world from getting off the fossil fuels by implying that we can counter GHGs effects with evaporation geoengineering schemes – remains a denier’s wet dream.
TK: “ [opponents] remarks show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals. ”
writes … Tomas Kalisz, who have posted for months on Lague et al., EVEN THOUGH he has not taken any climate courses, wasn’t interested in reading climate textbooks, even few months ago didn’t understand such basic concepts as the differences between fluxes and reservoir size,
“ Do as I lecture you, not as I do “?
And to make thing better, demands that the top climate scientists in the world explain things to him, when he didn’t bother to do his damn homework. And bitterly complains when they don’t.
I hope that I already know the relationship between reservoir size (atmosphere volume above a selected surface area multiplied with the average absolute air humidity therein), flux (average annual precipitation over the selected surface area) and residence time (reservoir size divided by flux), I do not understand how you from a short (in global average) water vapour residence time derived your conclusion that the direct effects of anthropogenic changes in evaporation “disappear after days”.
I would rather expect that if we changed e.g. the water availability for evaporation, the respective changes in water cycle intensity and/or air humidity may persist until the water availability for evaporation changes again.
Are you indeed sure that your comparison of residence time of water and CO2 has any predictive value for relative importance of the respective anthropogenic changes for Earth climate?
Greetings
Tomáš
Piotrsays
Toams Kalisz: I hope that I already know the relationship between reservoir size (atmosphere volume above a selected surface area multiplied with the average absolute air humidity therein), flux (average annual precipitation over the selected surface area) and residence time (reservoir size divided by flux),
That you can repeat their definitions, does not mean that you understand “the relationship between these three” nor their implications to the schemes you promote here. As is obvious from your next sentence:
TK: “ I do not understand how you from a short (in global average) water vapour residence time derived your conclusion that the direct effects of anthropogenic changes in evaporation “disappear after days” ”
The water vapour residence time of 2-10 days MEANS that if you ADD water vapour to the atmosphere – it will be GONE from there by 2-10days – hence your extra vapor affected the climate only for the same 2-10 days.
As opposed to CO2 where the residence time of our human perturbation is in many DECADES, and therefore removal of GHGs now will continue to affect the climate for DECADES.
So only somebody who has no idea of the MEANING of even such a basic concept as the residence time – would push for diverting the research and AGW mitigation efforts from reduction of GHGs (effects lasting for decades) to increasing evaporation (effects lasting for 2-10 days).
And only somebody completely full of himself would assume that he, must be really really smart if despite knowing next to nothing about climate science – he, Tomas Kalisz, just invented a feasible solution to the AGW that all the climate scientists in the world working on those issues for decades – MISSED!
Thank you for confirming that we use the same residence time definition.
As regards your assumption that the average residence time of water vapour (about ca 8-10 days) in Earth atmosphere can imply that any human interference with water cycle (or, more generally, any change in water cycle) has a negligible influence on Earth climate, because its effect must disappear within this short time, I must, however, respectfully disagree.
It is because these interactions do not comprise the water vapour atmospheric concentration only. I think that Lague 2023 is a valuable asset especially because it quite clearly showed that although dramatic changes in water availability for evaporation from the land have small effect on water vapour concentration (because absolute air humidity spreads from the oceans over land even in case that there comes no water vapour from the land at all), the changes in latent heat flux, and, furthermore, the changes in cloudiness, both resulting from this “forcing”, can be very significant.
Lague 2023 suggests that an increase in evaporation from the land can, counter-intuitively, result in a decrease in mean absolute air humidity, due to higher global latent heat flux, higher global cloudiness and lowering of of global mean surface temperature. These effects are not expected to disappear after 10 days, oppositely, they are expected to persist as long as the higher water availability for evaporation from the land persists.
That is why I think that your assertion about negligible influence of changes in land hydrology on global climate, construed from the short residence time of water vapour in Earth atmosphere, may be in fact incorrect and misleading.
Greetings
Tomáš
Piotrsays
T. Kalisz.: Dear Piotr, Thank you for confirming that we use the same residence time definition.
Definition of the residence time has not been the subject discussion since that time I had to explain to you the difference between a flux and reservoir size. Here the point is that you parroting the words of the definition without the slightest ideas what it means to your lunatic irrigation schemes.
P: [the residence of WV in atm is in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs. Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
TK: “I would rather expect that if we changed e.g. the water availability for evaporation, the respective changes in water cycle intensity and/or air humidity may persist until the water availability for evaporation changes again”
No – when after a WEEK – the VW you added to the system is gone – no cloud for cooling – no surplus warming from increased VW concentration the heat reradiated into space of the ground – YOU HAVE TO START again – and week and a week after and a week after. Compared that with removal of CO2 that does not have to be repeated by many DECADES.
Kg per kg water vapour is BY FAR LEAST effective greenhouse gas – its 100-year GPW (Global Warming Potential,) compared to 1 kg of CO2) is = -0.001 to 0.0005.
Which means that to have any measurable effect not only you have repeat evaporating week after week after weak, but each time you have to evaporate MASSIVE amounts of water vapour – which to make it worse – is NOT available on the deserts – the only source being 1000-FOLD increase in desalination – with its astronomic cost and energy-use – hence GHG-generate by the massive desalination and transport over 5 mln km2 over MANY CENTURIES.
In other words if there was an Ig-Nobel Award – for the MOST IDIOTC, MOST COST-INEFFECTIVE, way to mitigate the AGW – you and your JCM would have been the laureates.
I agreed to that if the effect of human interference with water cycle has to be observable, it must persist.
You are therefore correct that in case of an artificial increase of water availability for evaporation from arid areas such as Sahara, it is hardly imaginable without a steady supply of the required water.
Past human interferences with land hydrology, however, might have had rather the opposite effect. There are authors, like Makarieva et al, who suppose that deforestation and/or unsuitable agricultural practices might have impaired rain recycling over entire continents,
Speculations that through a feedback loop, these changes might have finally resulted in substantial decrease of water availability in entire regions thus significantly contribute to their desertification, are difficult to prove or disprove, because it seems that our knowledge regarding past global precipitation and its geographic distribution are still extremely limited.
Furthermore, there seems to be still a knowledge gap with respect to the relationship between water availability for evaporation from land and global climate sensitivity towards other forcings.
It is, however, clear that if above described human activities like land deforestation indeed changed continental water regimes, the respective changes in water availability for evaporation persist. In this sense, your argument based on short mean residence time of water vapour in Earth atmosphere may be completely irrelevant.
For all these reasons, I still think that your claims about negligible influence of human interferences with land hydrology on global climate are too bold.
Greetings
Tomáš
Piotrsays
Tomas Kalisz: Aug. 25 “ There are authors, like Makarieva et al, who suppose that deforestation and/or unsuitable agricultural practices might have impaired rain recycling over entire continents”
One could “speculatively suppose might have” ANYTHING. It counts whether one can support quantitively their speculations – here by calculating that significant part of AGW was caused by deforestation. Neither Makarieva, nor you, did.
TK if above described human activities like land deforestation indeed changed continental water regimes, the respective changes in water availability for evaporation persist. In this sense, your argument based on short mean residence time of water vapour in Earth atmosphere may be completely irrelevant.
Neither you nor your Makarieva did quantify the effects of deforestation on global T.
But what you failed I could try with the help of your another source Lague et al 2023:
– EVEN if we assumed that all agricultural land has been created by deforestation, that there is no irrigation of the fields, and the Lague’s 8K difference between all land being swamp, and all land having zero evaporation – the maximum effect would be warming by ~ 1K.
But in REALITY it would be only a tiny fraction of that ~ 1K:
1. we need to reduce the area of the agricultural land by fraction of cropland that hasn’t been created by deforestation (Eurasian Steppe, Prairies, Pampas, Savannas, most of agricultural land in Australia, irrigated semideserts (Central Asia, River Nile etc)
2. neither croplands have zero evaporation, nor many forests have the evaporation of a swampland, hence the actual effect on global T is only a fraction of the max. difference calculated by the difference between a swamp and zero evaporation
3. the reduction in evaporation due conversion to cropland may be compensated by irrigation, used precisely in the places where the evaporation is otherwise limited.
Therefore, instead of 1K warming – we have a fraction, of a fraction of 1K, that may be further offset by the increase in evaporation due to irrigation.
So to borrow your phrase – it is you, Mr. Kalisz, who “ may be completely irrelevant” here.
provide, from very different perspective than Lague et al, another hint in the same direction.
I understand their article similarly as Lague 2023 – the way that anthropogenic changes in terrestrial hydrology indeed might have contributed to the observed AGW.
I recommend reading the fulltext, it is also an open access article. If you do so, you will find out that not only Lague but also Makarieva et al in fact tried to provide a quantitative esstimate for this anthropogenic effect:
“Historical deforestation affected about 13% of land area Sl=1.5×108 km2 (or 3.8% of planetary surface SE=5.1×108 km2) (Figure 1). With the global mean latent flux of FL = 80 W m−2, if deforestation has reduced this flux by thirty per cent (ΔFL ~ −0.3FL), this could increase the surface radiation by −0.038ΔFLΔτ ~ 0.9 W m−2 (cf. Figures 3D, E, Δτ = 1) or twice that number (cf. Figures 3D, F, Δτ = 2), Table 1. Given an equilibrium climate sensitivity ε ~ 1 K/(W m−2) (Zelinka et al., 2020), the latter case corresponds to a warming of about two degrees Kelvin (Table 1).”
I do not overemphasize the accuracy of both estimations (by Lague and Makarieva), because it is obvious that quantitatively, they substantially differ from each other. What I see potentially important, however, is the circumstance that despite of very different approach, both estimations qualitatively point in the same direction.
Greetings
Tomáš
Piotrsays
Tomáš Kalisz 27 Aug
“Makarieva et al provide, from very different perspective than Lague et al, another hint in the same direction.”
The role of papers in climate science is NOT to provide wishy-washy “speculations” and “hints” on what “ supposedly might have” been the case, but quantitative evaluation of the speculations. Neither you nor your Makarieva delivered it – since neither of you quantified the effects of deforestation on global T.
That’s IN CONTRAST’s with Lague et al. – who provided NUMBERS for the global effects on T of two extreme cases, which then in turn allows us to put QUNATITATIVE constraints on the effects of deforestation on global T.
Which as I have shown, in the post to which your “reply”, to be:
“ a fraction, of a fraction of 1K, that may be further offset by the increase in evaporation due to irrigation ” – for details see my post from Aug.26 you are supposedly replying to.
So, my dear Kalisz, your claim that Makarieva results were “ in the same direction ” as the analysis based on Lague et al – is a LIE,
And so much for your? Makarieva? effects of what “might have impaired rain recycling over entire continents” on global T.
TK: “I recommend reading the fulltext”
says the guy who can’t understand even simple post on RC, not even the implications of his OWN posts …
The onus of proving YOUR claims is not on the reader, but on its author – YOU have find the quotes in Makarieva in which she quantifies the effect of changes in water cycle by deforestation – as being MUCH bigger than “a fraction, of a fraction of 1K globally, that may be further offset by irrigation ” – based on the quantitative results of Lague et al.
Nigeljsays
Tomas Kalisz:
“It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.”
This sounds weird. How can the concentration water vapour, a greenhouse gas increase and yet concentration of greenhouse gases remain constant?
“I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.”
No more vague than your statement: “Residence time of water vapour in atmosphere is a variable that has an extreme broad range”
I have not followed the endless debate between you and Piotr in detail, but his point seems to be that you have this desert land and swamp land scenario and a certain temperature differential and when you look at what humans have done and could practically do to shift earth from one extreme to another it looks like it would fall far short of the calculated temperature differential. His comments are a sort of first approximation but his quantitative reasoning looks good. You havent even provided a first approximation to defend your own argument.
“Residence time of water vapour in atmosphere is a variable that has an extreme broad range”
From the study “The residence time of water vapour in the atmosphere”…”The time water spends in the atmosphere, or WVRT, is a fundamental diagnostic of the climate system. WVRT varies widely, ranging from less than 2 days over the subtropical oceans to more than 10 days at high latitudes, reflecting regional differences in precipitation-generating mechanisms.”
Is 2-10 days extremely broad? I dont think so but its hard to define what extremely broad means. However 2 – 10 days does not come even remotely close to the residence time of CO2 in the atmosphere. which is measured in centuries. This is the point Piotr made and its irrefutable.
“just a few remarks that show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.”
Yet you are not a climate science professional and you have posted numerous comments on Lague. So you are practicing double standards.
Its a public forum so anyone will comment on anything. Deal with it! I think its best to focus on the content of what people say, and not worry too much about their qualifications.
As regards the residence time of water vapour in the atmosphere, if we take the simplest definition thereof as the ratio of the annual sum of precipitation over certain area to the average overall amount water comprised in the air column above this area, and assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year. Taking into account that there are desert areas with a significantly lower annual sum of precipitation, you can roughly estimate that water vapour retention time on present Earth may vary in the range from single days to tens of years. I am not sure if comparing this parameter for water and non-condensing gases makes any sense.
As regards Piotr’s calculations of the cumulative effect of forest conversion into cropland by humanity, I offered a much simpler example of conversion of ca 5 million square km of wetland into desert (or vice versa), with a similar direct effect on mean global surface temperature about 0.3 K. I think that a discussion, systematically restricted by Piotr just to a question if such direct effect of 0.3 K is significant or negligible, makes little sense without a broader context which I tried to address e.g. in my post of 4 Aug 2024 at 7:57 AM,
As regards the content of my “comments” on Lague in their entirety, I do not think that I apply a double standard. I believe that if you read them, you would rather say that I just asked questions inspired by the article and/or expressed my doubts if bold conclusions derived therefrom by Piotr (in the sense that “human interference with terrestrial water cycle has a negligible influence on Earth climate”) are indeed justified.
I still think that these doubts were not addressed in comments provided by Piotr, at least not the way that would help to resolve them or to clarity that they may be indeed relevant. If they were addressed, I would spare my calls if someone else could perhaps do so.
A specific example: My attempt to suggest that there may still be an open question what is the influence of water availability for evaporation on climate sensitivity – which could influence earth climate significantly even in case that the direct effects thereof were indeed negligible – was simply dismissed by saying “your suspicions and feelings are irrelevant”.
Of course this is also a possible way how to discuss. I just think it is not the most productive one.
Greetings
Tomáš
Barton Paul Levensonsays
TK: if we take the simplest definition thereof as the ratio of the annual sum of precipitation over certain area to the average overall amount water comprised in the air column above this area, and assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year.
BPL: You’re assuming no moisture-bearing winds in or out of the area.
The average residence time of water vapor in the atmosphere is 8.9 days.
Tomas, you should read Nigel’s citation. Your definition is clearly idiosyncratic at best.
And given that it arrives at a radically different value than given in a review article, there’s good reason to think it is completely wrong.
Piotrsays
Tomas Kalisz “ I offered a much simpler example of conversion of ca 5 million square km of wetland into desert (or vice versa), with a similar direct effect on mean global surface temperature about 0.3 K.
For some reason you forgot mention that your “simple” scheme would also:
– require increasing the current global desalination ~ 1000-FOLD,
– pumping huge volumes of desalinated water over 1000s of km of pipes to spread it over over 5 mln km2
– have to be maintained for at least THOUSANDS of YEARS to even approach that 0.3K cooling – the 0.3K assumes formation of the swamp vegetation over half of the Sahara. vegetation requires, among other, soil; formation of 1 cm of soil takes ~ 200 years)
– the amount of GHGs emitted to the atmosphere to do the desalination and distribution of the water over THOUSANDS OF YEARS – would cancel most, or even reverse, that 0.3K cooling.
In other words, your modest proposal is to spend trillions of dollars year after year over 1000s of years to achieve …. a miniscule cooling or even a net warming.
With modest proposal like yours – who needs J. Swift?
The reference provided by Nigel is very interesting, however, not easy for me as a layman and I will need time to grasp the message (if I will be able to grasp it at all).
Nevertheless, I think that the definition of water vapour residence time which used in my example is in accordance with the reference provided by Barton Paul. Please note the end of the first paragraph in the right column on the first page of this article, which reads:
“All of these examples estimate the global average residence time of atmospheric moisture based on the size of the atmospheric reservoir divided by the incoming or outgoing
flux and as such arrive at estimates in the range of 0.022–0.027 years or 8–10 days.”
I no way disprove this mean value, nor the conclusions made in the more recent article cited by Nigel. I do not think they are in a discrepancy with my example, which does not speak about averages over a range of latitudes but about a more granular view on geographic regions with specific hydrological regimes. The purpose of this example was to show that at regional level, the variability of water vapour residence time is much bigger than the range derived from averaging it globally or over a range of latitudes.
Dear Barton Paul,
Thank you for the reference.
As regards your objection, I think that the absolute humidities about 5 g water in 1 m3 air observed over hot deserts like Sahara have to be indeed explained by long-range water vapour transport.
If I considered that the water vapour above my exemplary desert with annual sum of precipitation 50 mm came solely from local evaporation, then, assuming the residence time about 0.03 year, its mean atmospheric concentration would have been as low as 0.15 g/m3.
In such case, the corresponding mean relative humidity in this region would have been close zero, in discrepancy with mean relative humidities observed in desert regions like Sahara, which are to my best knowledge somewhere in the range 20-30 %.
I therefore still suppose that my example considered the reality of the long-range water vapour transport properly and that the long residence time of water vapour over hot desert regions of Earth is in fact a direct consequence of this long-range transport.
Greetings
Tomáš
Piotrsays
Kalisz: if assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year.
BPL: You’re assuming no moisture-bearing winds in or out of the area.The average residence time of water vapor in the atmosphere is 8.9 days.
Kalisz is like Trump – makes poorly formulated and different statements, so when questioned he can choose the one that fits the moment.
– in this post, to inflate the residence time of water vapour from days to “1 year” – he “assumed” no horizontal movement of air with moisture
– in another post – his compliments Lague et al. on showing …. the importance of the said horizontal movement or air with moisture from the ocean onto a desert.
By making two opposite assumptions he is bound to be always right … ;-)
knows it – because he was lecturing others for not reading Lague et al who show that even with zero evaporation from land – there is water vapour over it
I tried to draw a preliminary conclusion from our debate.
Let us see if someone will dissent with Piotr’s view.
Greetings
Tomáš
Piotrsays
Tomas Kalisz: “Dear JCM, Welcome back from your vacation.”
What, no flowers?
TK: I am not completely sure yet if Piotr indeed does represent everybody on this website, including the hosts.
What a …weird thing to say, given that I never claimed that I represent anybody but myself, and my arguments rely on logic and facts, not on “representation”. Fighting your strawmen often, Mr. Kalisz?
TK: Let us see if someone will dissent with Piotr’s view.
What for? You have ignored the criticisms of the same claims by others before, so what would be different now?
Of course that you write for yourself. I just tried to express my feeling that the majority of discussion participants herein shares your views.
I asked my question if someone’s view perhaps differs from yours because the present question – if others share also the view that my questions can undermine the reputation of climate science – is important for me.
Greetings
Tomáš
Piotrsays
Tomas Kalisz: “if others share also the view that my questions can undermine the reputation of climate science ”
To “undermine the reputation of climate science” you would have to know something about the science.
Your capability as an uneducated in it denier are much more limited -because the deniers don’t need to refute the climate science with a better alternative explanations – all they need is to “seed the doubt” and spread it via Internet, where every opinion is equally valid, a post from Gavin has to the general public the same weight, as a post from Tomas Kalisz, JCM, or other Mr. Know it Alls.
And once the doubt has been spread and seeded – it can be used for plausible deniability by the politicians to block action on the GHG reduction and continue trillion dollars subsidies to the fossil fuel interests – if:
– “The science is not settled”;
– “There are major knowledge gaps”
– the science does not want to address them,
– ” it is hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
– human changes of the water cycles have “ mindboggling ” effect on AGW
changes in the water cycle] due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
– the climate science is “ artificially fixated and overemphasize the role of trace gases” while resulting in the global desertification
then – let’s not rock the boat until the science is settled, let’s redirect the research and money from GHG mitigation to the non-GHG geoengineering. And in the meantime lets continue the corporate welfare for the fossil fuel industrial complex:
“ Globally, fossil fuel subsidies were $7 trillion or 7.1 percent of GDP in 2022,” (source: IMF)
Even though your role in this is that of a small cog in a machine – it is irrelevant to the ethical evaluation of your actions as an individual – you are what you support. Whether you support it as a paid troll, or more likely, as a “useful idiot” of the fossil fuel interests – does not make much difference. By their fruits you shall know them.
Barton Paul Levensonsays
JCM: Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. . . . Obviously this directly opposes the bizarre distortions on display by respondents. Global landscape hydrology is a huge known information gap which is increasingly recognized. When detractors say things like “both of you REFUSE to acknowledge the conclusions” it doesn’t make any sense at all.
BPL: Why don’t you write to Dr. Lague and ask him what he meant?
Piotrsays
JCM: “Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. . . . Obviously this directly opposes the bizarre distortions on display by respondents.
BPL: Why don’t you write to Dr. Lague and ask him what he meant?
Well, it’s her (“Larysa”). But the more important point that the authors are rarely the objective judges of the importance of their own work. ;-) So a more informing question would be
====
what % of Delta T= 8K between the two EXTREMES (all continents a desert minus all continents a swamp) could possibly be attributed to the net (direct) changes in evaporation by humans (e.g. reduction due to deforestation minus increase due to irrigation).
In other words – whether the human ALTERATION of the natural evaporative fluxes is, has indeed a “mindboggling” and is “profound forcing of AGW, and therefore her paper supports JCM attacks on the existing climate models – where he blames “ the planet’s land degradation and loss of native ecologies on the climate models being “ artificially fixated and overemphasizing [ the role of GHGs in global T changes] :
“ UNCCD reports up to 40 % of the planet’s land is degraded and annual net loss of native ecologies continues unabated at >100 million ha / decade. This is a profound forcing to climates and puts our communities at risk. It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases ” (c) JCM
It might be interesting to see whether Dr. Lague agrees with JCM’s use of her name and her work.
Russell Seitzsays
BPL : You rang ? Sen the contact info you requested weeks ago.
Barton Paul Levensonsays
RS,
I was looking over our long conversation about nuclear winter/autumn five years ago, and I realized I used very intemperate language and even swore at you a couple of times. I’m ashamed now that I acted that way and I would like to apologize. I should apologize, as well, for waiting so long to do this.
JCMsays
Thanks BPL. Although I think the meaning of Lague’s remark is only ambiguous to those who want it to be. It simply opens the door for future research. I noticed she is now in partnership with Gordon Bonan who’s career has focused on human disturbance to forest systems specifically. Their next article in press is Reimagining Earth in the Earth System. at Journal of Advances in Modeling Earth Systems (2024).
Human and natural changes to the land is the obvious trajectory of her career, including interesting stuff about continental configuration. These biogeophysical and biogeochemical effects are complementary the early simpler geophysical perspective focused on fluid dynamics and radiative forcing in GCM.
Lague’s specific article here only makes reference to a linear change to evaporative resistance in units s/m. As I previously mentioned long ago, the proportional analysis introduced by Patrick o is slightly misleading because for 1 unit change in resistance has the same response regardless of the initial condition. She clarifies in lecture that other unexplored factors may not be linear, such changes to surface roughness. In other works specific to forests, Bonan is interested in BVOC and aerosol changes related to forest change. Lague’s ET is just piece of the puzzle. Personally I am most interested in soils.
cheers
Piotrsays
Re: JCM Aug 15.
Your (JCM’s) saying that Lague’s paper: “ simply opens the door for future research. ” is cop-out AFTER you quoted her statement: “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change”
In support of your claim about “mindboggling” importance of the human changes in water cycle to AGW, and in support of your blaming the climate models for: the planet’s land degradation and loss of native ecologies [due to] an artificial fixation and overemphasis on the outputs of trace gases ”. (c) JCM
For THAT – you, or YOUR SOURCES has to answer a question I have already posed to you:
– ” what % of Delta T= 8K from Lague et al 2023 between the two EXTREMES (all continents a desert minus all continents a swamp) could possibly be attributed to the net (direct) changes in evaporation by humans (e.g. reduction due to deforestation minus increase due to irrigation).”
– and to show that the result (= % * 8K) is significantly LARGER than the increase in T caused by the increases GHGs,
“ Simply opens the door for future research. ” doesn’t deliver either.
Your perpetual repetition of your cropland example does not resolve anything, and you already have to know it.
Besides the circumstance that your example is speculatively parametrized and thus prone to endless discussions if this or that arbitrarily set value is really suitable and reflecting reality or not, I am afraid that your arguments suffer from further severe deficiencies:
1) You seem to take the quantitative estimations of Lague 2023 as given, whereas it is quite clear that they can be even lower (in this case supporting your “delta t less than 0.3 K” claim even stronger), but equally well they can be significantly higher, thus making your claim weaker.
2) Even in case that your “delta t” claim was fully justified and strongly supported with undisputable data showing that the direct influence of changes in water availability for evaporation indeed have a negligible influence on global mean surface temperature, I insist in my opinion that your conclusion speaking about “influence on global climate” is an unjustified generalization.
Global climate is not the same as global mean surface temperature, and if something can have an influence on temperature, we have to ask if perhaps its influence on precipitation (amount thereof, and distribution thereof) is also (un)important. Lague 2023 seems to suggest very moderate influence of dramatic changes in water availability for evaporation to precipitation patterns, whereas reality of Earth’s deserts suggests that this influence might be very strong.
3) Moreover, so far we spoke about direct effects only. It still remains, however, completely open if changes in water availability for evaporation can or cannot have very pronounced indirect effects on global climate, through possible influence thereof on climate sensitivity.
For all these reasons, I would be personally quite cautious in drawing bold conclusions like “human interferences with water availability for evaporation have negligible influence on global climate”.
Greetings
Tomáš
Piotrsays
T. Kalisz Aug.21 Your perpetual repetition of your cropland example does not resolve anything, and you already have to know it.
That’s because your hero, JCM, as a part of his denier’s agenda “Anything by GHGs” have used Lague et al as a proof of “mindboggling” (JCM) potential of mitigation of GHG by human changes by humans water fluxes, and that “mindboggling potential” presented as a proof of climate science’s “ artificial fixation and overemphasizing [the role] of trace gases”.
To which I just remind him that even the largest human impact on the water cycle agriculture – based on the data of his Lague et al. – produced LAUGHABLE small effect on global T – “ a fraction of a fraction of a 0.3K”
The only OTHER proposal on the table to alter global T via human intervention in the water cycle – was Tomas Kalisz LUNATIC idea of watering Sahara into a swamp by increasing the present global desalination 1000_FOLD and maintaining it for many HUNDREDS/THOUSANDS OF years to even approach 0.3K colling, an effect that is likely to be cancelled by all the emissions of GHGs over the HUNDREDS/THOUSANDS of years of operating your scheme.
JCMsays
Every now and then, I feel it’s important to reiterate that I have never claimed any miraculous potential to compensate fossil fuel emissions through landscape stabilization.
I recently realized that this misunderstanding might stem from arbitrarily placing these concepts within a geoengineering framework. However, I strongly disagree with labeling the stabilization of functional ecologies as geoengineering, in the same way that solar radiation management, strategic tree planting for carbon drawdown, or artificial irrigation schemes are classified. The geoengineering perspective overlooks the fact that the loss of ecosystem function has already directly contributed to regional, and potentially global, climate change, in addition to the atmospheric radiative forcing caused by fossil fuel pollution. The forcing and feedback mechanisms at play are distinct from those associated with trace gases. Ecological stabilization is fundamentally different from deploying an engineered compensation scheme because the loss of functional ecosystems is itself a historical forcing.
That being said, ongoing deliberate distortions, misrepresentations, and twisting of words is clearly being done in bad faith regardless of whatever misunderstandings persist. Taking phrases out of context and rearranging them to completely alter the message is, in my opinion, a particularly low tactic. I once again request that participants cease this behavior. If these actions are not intentional but instead stem from deeply ingrained biases, I encourage you to reflect on this. Consider taking into account how the destruction of functional ecosystems might contribute to anomalous hydrological and temperature extremes. This includes, but is not limited to, drainage and channelization of landscapes, chemical biocide application, soil desiccation, loss of biodiversity, and impaired watershed function.
While the most acute erosion to rockflour might occur on a subsidized cash-crop parcel, the effects are present throughout our communities and beyond, ranging from the forested hills to the central valley. We are witnessing a widespread, ongoing, and unrelenting deterioration of landscapes across the vast majority of the Earth.
It appears that you prefer dealing solely with direct effect of changes in water availability for evaporation on global mean temperature.
In this point, I agree to you that the estimates made in Lague 2023 suggest that this direct effect is small. If you are not going to address other points that I have raised, I think we should stop this exchange because it does not bring anything new.
Greetings
Tomáš
Piotrsays
JCM 24 Aug 2024 “ Every now and then, I feel it’s important to reiterate that I have never claimed any miraculous potential to compensate fossil fuel emissions through landscape stabilization
Every now and then, I feel it’s important to confront your declarations with your actual words, e.g.:
====
JCM, June 5 “Join me in celebrating world environment day today June 5th 2024! This year focuses on land restoration, halting desertification and building drought resilience under the slogan “Our land. Our future”. UNCCD reports up to 40 percent of the planet’s land is degraded and annual net loss of native ecologies continues unabated at >100 million ha / decade. This is a profound forcing to climates and puts our communities at risk. It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gas and aerosol forced model estimates.”
===
So, HOW ELSE do you explain your contrasting “ profound forcing to climates” by the human alteration to water cycle, with “an artificial fixation and overemphasis” on GHGs, IF NOT that we should therefore DIVERT the attention and money from “trace gas” mitigation toward changes in the water cycle that provide profound forcing to climates” ?
HOW ELSE do you explain your INSISTENCE on calling GHGs “trace gas”, even though
the term is scientifically sloppy – not properly defined (the analytical chemistry’s definition of “trace” is <100 ppm, i.e. well BELOW the CO2 conc.) and open to manipulation (e.g. to imply that "trace gas" may have only "trace" influence).
All of the above fits well with:
– the main denier's narrative " Anything but GHGs”
– the denier’s standard attacks on the credibility of climate science (“an artificial fixation and overemphasis”)
– describing the terrible consequences of heeding the advice of science on reductions to GHGs:
“40 %of the planet’s land degraded” just before: “ It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gas and aerosol forced model estimates.”
By their fruits, not their declarations about themselves, you shall know them.
Global climate is not the same as global mean surface temperature…
Correct, and this is precisely why ARs discuss at chapter length other aspects of climate. Not sure why I have to reiterate this point.
….and if something can have an influence on temperature, we have to ask if perhaps its influence on precipitation (amount thereof, and distribution thereof) is also (un)important.
Not sure what the “something” is supposed to be here. But in any case, the interplay of temperature and precipitation is already the subject of considerable study. So I don’t think we “have to ask”; this question has already been asked, and continues to be investigated. In fact, I think there are already some answers. (E.g., AR chapters dealing with precipitation, soil moisture, drought and the like.)
Lague 2023 seems to suggest very moderate influence of dramatic changes in water availability for evaporation to precipitation patterns, whereas reality of Earth’s deserts suggests that this influence might be very strong.
Globally–our concern here–rather than locally? How so?
Moreover, so far we spoke about direct effects only. It still remains, however, completely open if changes in water availability for evaporation can or cannot have very pronounced indirect effects on global climate, through possible influence thereof on climate sensitivity.
Just as it remains completely open whether or not there is a chocolate cake orbiting Jupiter. You haven’t answered any of the fundamental questions as to how your proposed “indirect effect” might work in reality.
–How could ‘water availability for evaporation’ possibly change on a global scale possibly change drastically, given that 70% or so of the planet is ocean, and that despite humanity’s proven ability to degrade ecosystems there are very real practical limits on our ability to fundamentally transform hydrology on the remaining 30%?
–If you propose, as you seem to, that such transformation is presently altering the climate–again, our concern on this site–then where is the evidence? We have been monitoring and studying atmospheric water vapor, in part because we know it’s an important radiative feedback. Is there one single study out there presenting evidence that the rise in absolute humidity is causing observed warming, rather than (as we know from solidly-established theory should be the case) being caused by that warming?
–If you provided a mechanism by which a “possible influence on climate sensitivity” could exist on this planet, I missed it. It’s clear that you have an *expectation* that such an effect should exist, but it’s unclear to me, at least, why that would be. It’s particularly unclear to me why such an effect might be *larger* than the “direct effect.”
(In this respect, I’m returning to my old thought experiment about Arrakis, Frank Herbert’s implausible but enticing imaginary desert world. Clearly–and contrary to my initial thoughts–climate sensitivity on Arrakis should be low, because important feedbacks that exist on Earth are extremely limited on Arrakis. There’s not much water vapor feedback because there’s very little water anywhere on the surface; there is no ice to melt and thereby change albedo; and there’s very little vegetation to affect albedo, either. (That’s the most implausible thing about Arrakis, IMO; where’s the primary production to support those giant sandworms?) So there, doubling CO2 would not increase temperature much beyond the direct radiative effect. But there’s no way–thank God!–to turn Earth into Arrakis, short of exporting most of our water off-world. We aren’t limited by the availability of water; and in fact, the sheer abundance of it on a global scale makes it very challenging to explain why local anthropogenic changes in water availability wouldn’t effectively be swamped by the global warming-driven increase in specific humidity.)
I am not sure if you noted that the disputed article Lague 2023
(open access under https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1/pdf ) suggests that an increase in water availability for evaporation may in fact DECREASE the mean global temperature and global mean absolute humidity, while the global latent heat flux increases. This is why I asked if the generally accepted view that “water vapour feedback” must any time augment GHG forcing is indeed as general as assumed. Are you sure that the magnitude of this feedback (and, possibly, also its sign) is/are independent from water availability for evaporation?
In view of Lague 2023 who provided an opposite estimation than previous discussions on this website (wherein majority of participants asserted that improving land hydrology / intensifying water cycle by providing more water for evaporation from the land must warm the climate (“because of water vapour feedback”)), I can well imagine that the present “water vapour feedback rule” was derived for the present Earth with its present level of soil humidity, terrestrial vegetation and precipitation distribution, and nobody has ever asked how this “rule” looked like for the Earth 200, 500, 1000, 2000 and 5000 years ago.
Maybe that the results achieved by Lague 2023 came from peculiarities of her climate model – that is why I am curious how her experiment would have looked like using other models. Nevertheless, if her results indeed suggest that higher water availability for evaporation in fact DECREASES global mean surface temperature, then I think that my suggestion to look if good water availability for evaporation might perhaps rather stabilize the climate against other forcings than destabilize it (as generally assumed on teh basis of the “water vapour feedback” estimated for present Earth) may be more relevant than a suggestion to investigate if there is a chocolate cake on Jupiter orbit.
I think so because results of Lague 2023 suggest that even though we have a planet with 70 % ocean, it may not be a guarantee against continental desertification. I can well imagine that we could arrive at hot continents with lot of water vapour on a clear sky thereabove, as described in Lagues “desert land” scenario. And, contrary to the results achieved by Lague 2023 which do not suggest any dramatic change in precipitation, I am afraid that the situation of “continental heat islands” might in fact result in a significant decrease of terrestrial precipitation, and in real desertification of entire continents.
That is why I share JCM’s concerns that by poor agricultural practices and further human activities, causing soil degradation, we may start a feedback loop that can bring us dangerously close to a such Arrakis-Earth.
Greetings
Tomáš
Piotrsays
Tomas Kalisz: “It appears that you prefer dealing solely with direct effect of changes in water availability for evaporation on global mean temperature.”
What are you trying to say? What are these … “ indirect effects” which are NOT small, but I for some, presumably nefarious reason, try to avoid discussing?
And why do you imply that these “indirect effects” – have NOT been ALREADY
accounted for in Lague’s by using quite a complex climate model?
After all, it was your guru JCM who brought and promoted the Lague’s paper, while you used it as proof to that your stupid Sahara irrigation schemes have indeed merit?
Aren’t you trying to snatch victory from the jaws of the defeat – by portraying my holding JCM and you to account for your claims, as … “insisting” on talking about things nobody discussed here. And trying to make virtue out of your attempt to change the original subject of the discussion, under the threat of you proudly walking away?
TK If you are not going to address other points that I have raised, I think we should stop this exchange because it does not bring anything new.
When the going gets tough, the tough get going ? ;-)
Piotrsays
Tomas: Global climate is not the same as global mean surface temperature…
Kevin: “ Correct, and this is precisely why ARs discuss at chapter length other aspects of climate. Not sure why I have to reiterate this point.”
Because the “anything but GHGs” deniers, having failed to prove that humans can compensate for the entire, or at least substantial part of, warming by the GHGs by increasing evaporation, change the subject by lecturing opponents that
“ Global climate is not the same as global mean surface temperature“.
That sentence has also another undertone – it detracts the attention from the fact that most of the global climate change is driven by AGW (global increase in T), and most of the AGW is driven by increased GHGs. There the most feasible, the most long-term, and the most cost-effective to mitigate global climate change – is to mitigate GHGs.
Which is anathema to the deniers, minimize the role of GHFs by saying: it is “only 0.04%” of atmosphere, or by calling them a “trace gas” (with the implication that a “trace” gas must have only a “trace” influence), and who blame global desertification and destruction of ecosystems on the climate science’s “ artificial fixation and overemphasis” on the role of GHGs. As our JCM put it:
“ hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the [role of “trace gases”] “
The next point of you feedback I would like to address are your questions about the mechanism of the hypothetical indirect effect of water availability for evaporation from the land, which, as I suggested, might consist in dependency of climate sensitivity towards other forcings to this parameter (i.e., water availability for evaporation).
In the previous part of my reply, I tried to show that Lague 2023 can be understood as a hint that do called water “vapour feedback” and “cloud feedback” may be much more complex mechanisms than considered so far, and that they may both depend on water availability for evaporation from the land. If you have not read Lague 2023 yet, I recommend to do so. It could make my explanations easier.
The above mentioned hint arises in my opinion particularly from comparison of Lague 2023 with another scenario studied previously using another model which included water vapour and latent heat flux only but not clouds. I think that this comparison justifies my question if the “cloud response” to GHG forcing, now considered as a positive feedback enhancing the GHG effect, must be really the same in other Earth configurations. To avoid recycling the argument that we cannot water present deserts, let us just look back. Are we sure that the clod feedback to GHG forcing was the same (as today) 200 years ago, 500 years ago, 1000 years ago or 2000 years ago, when continental hydrology possibly was quite different from its current state?
As regards my objection that quantitative estimations of Lague 2023 should be taken cautiously, because even her present model may not reproduce real precipitation patterns well: I took these patterns from the global perspective of precipitation partition between land and ocean. If Lague 2023 suggests that eater availability for evaporation from the land may, by combined feedbacks from latent heat flux, from the change in water vapour GH effect, and from the change in clouds, influence the global mean surface temperature, I think our primary concern should be the question if (and if so, how much) it can influence also this land-ocean precipitation partition. And, because precipitation can definitely play very important role in water availability for evaporation, if there can be a threat of negative feedback loop, by which anthropogenic changes in continental hydrology might cause desertification of originally humid and habitable regions.
The reason, why we should ask if water availability for evaporation can influence climate sensitivity towards other forcings, is in my opinion simple: If there are two or more identified forcings, wherein each of them may influence Earth climate alone, we should ask how the act in mutual interplay. And, from the historical perspective, as well as for the sake of shaping climate policies properly, I believe that asking my question if anthropogenic changes in continental hydrology perhaps might have prepared the stage for present GHG global warming, may be justified too.
Best regards
Tomáš
JCMsays
Very interesting, Piotr.
I’ve seen this meme “anything but GHG”. To clarify, my focus is on the importance of landscape stabilization, not just any arbitrary issue. Climate is just one aspect of the multiple co-benefits.
This contrasts with those ideologically opposed to the notion of human interference with Earth systems, as they try to find any excuse to avoid acknowledging the required remediation. Perhaps they feel humanity is too insignificant or that natural factors dominate. Whatever the case might be, obviously this is not my view at all. If you continue to associate me with denialists, it’s evident that you’re either not paying attention or deliberately misunderstanding. Are you aware of this?
No amount of effort to create a toxic or hostile atmosphere will push me away. You serve as a prime example of the fixation I mentioned. It is a serious societal issue and is widespread among governance boards, committees, and teaching at all levels. Although well-intentioned and passionate, many self-proclaimed environmentalists operate with a narrow, half-baked perspective, fueled by a strong sense of personal virtue and confidence. Our interaction is providing me with deeper insights into how this bias functions, the extent of the knowledge gaps, and the tactics used to enforce these views. I find this particularly valuable, as you seem to be a remarkable textbook example.
If additional funds are needed for monitoring and research to better formulate the realities outside, and improve both teaching and policy advice, then it should be sought immediately. That should be academic. Many thousands are involved in community conservation initiatives ongoing, but the grass-roots is no match for the scale of the issue. The distorted perspective you have chosen to enforce is unfortunately common nowadays, and in my opinion, it’s extremely counterproductive to our shared goal of Earth system stabilization.
Rediscovering landscapes does not undermine the validity of policy advice related to the CO2-enhanced greenhouse effect. Your argument exemplifies the classic zero-sum fallacy. I suspect your disregard for significant human impacts stems from the belief that acknowledging the profound deterioration of landscapes is inconvenient and much more challenging to quantify than the direct radiative forcing from fossil fuel emissions. No amount of hand-waving or speculative quantification schemes embedded in extreme ideological rhetoric will convince me otherwise. I think this should be obvious.
Piotrsays
JCM 27 Aug Very interesting, Piotr.
I doubt the sincerity of this: your very interest … completely evaporated before my proof how “anything but GHGs” applies to you. No wonder that you think that it may apply only to …. others:
JCM: “ I’ve seen this meme “anything but GHGs” .
As for the rest of your production – I am not interested in your declarations about yourself nor your opinions about others – by their fruits you shall know them – whether “ anything but GHG ” applies to you or not – can be falsifiable tested using your own words and logic. Which I have done in my “very interesting” post:
=== Piotr Aug.26: =========
“So, HOW ELSE do you explain your CONTRASTING “profound forcing to climates ” by the human alteration tof water cycle, WITH “ an artificial fixation and overemphasis” on GHGs?
How else, if not “ Anything (here: the water cycle) but GHGs“?
HOW ELSE do you explain your INSISTENCE on calling GHGs “trace gas”, even though you were shown that the term is scientifically sloppy – not properly defined (the analytical chemistry’s definition of “trace” is <100 ppm, i.e. well BELOW the CO2 conc.) and open to manipulation (implying that "trace gas" may have only "trace" influence).
========
I tried to explain why I think that so called “water vapour feedback” and “cloud feedback” may not be fixed parameters but rather functions of the actual Earth configuration, in which values of some important variables, e.g. the water availability for evaporation from land (studied as a climate forcing perhaps for the first time in Lague 2023), may change quickly and may be also substantially influenced by human activities.
If these feedbacks are in fact functions depending among other variables also on water availability for evaporation, then also climate sensitivvity towards concentration of non-condensing GHG may depend on water availability for evaporation.
I have not noted any reaction from you yet, so I would like to ask if my explanations were understandable and if you are satisfied therewith.
Thank you in advance and greetings
Tomáš
Piotrsays
Tomas Kalisz Aug. 30: “If these feedbacks are in fact functions depending among other variables also on water availability for evaporation, then also climate sensitivvity towards concentration of non-condensing GHG may depend on water availability for evaporation.
Because as it has been explained to you MANY TIMES ALREADY – humans CAN’T CHANGE your “water availability” ENOUGH to make a difference. If they could – changes in water cycle would have been a forcing, not a feedback.
And therefore to mitigate AGW – we need to reduce the FORCING – GHGs, and the effect of GHG reductions will be amplified by the changes in water cycle resulting from changes in GHG forcing.
I thought I’d looked at it, but it appears to be a different Lague opus than the one I had read earlier, so thanks for linking. Continuing:
I asked if the generally accepted view that “water vapour feedback” must any time augment GHG forcing is indeed as general as assumed.
Yes, the view is practically universal. That is because water vapor is, as has been well-known since 1860, a powerful GHG, and because warmer air can sustain more water vapor. More water vapor in the atmosphere cannot cool; and more warming will always enable higher potential specific humidity.
Are you sure that the magnitude of this feedback (and, possibly, also its sign) is/are independent from water availability for evaporation?
No, of course not. As the Arrakis discussion should have made plain, one can imagine (and Frank Herbert did imagine, more or less) a situation in which water constraint held the water vapor feedback to a very low value. What I question is whether there is any plausible scenario under which such a situation could arise on this planet. More on that later.
However, in the meantime I note that you seem to be suffering from a confusion. Your remarks seem to indicate that you think Lague (2023) somehow undercuts the general view of the water vapor feedback. In fact, the paper completely supports that view.
Here’s how it works in Lague.
1) They artificially constrain surface hydrology in the model. It takes pretty heroic parameters to do so:
In DesertLand, the first of our extreme simulations, the capacity of the land to hold water is reduced to 20 mm everywhere (compared to a typical value of ≈200 mm), and the resistance to evaporation is set to 100 000 s m−1 (compared to a typical value of ≈100 s m−1); this effectively turns off evaporation from the land surface, regardless of precipitation
or the atmospheric demand for water. DesertLand can physically be thought of as land free of vegetation with extremely well draining soils, such that all precipitation that falls on the land is quickly transferred into below ground aquifers or sub-surface run-off and returned to the oceans. In SwampLand, the second extreme simulation, the land surface is forced
to be fully saturated with water at every time step. Land always has 200 mm of water available for evaporation, regardless of the precipitation or evaporation rates at each point. SwampLand can be thought of as land with a high water table and unlimited
ground water supply. Physically, this is comparable to swampy regions on the modern land surface, but in this idealized simulation, these swamps are imposed over the entire non-glaciated land surface, regardless of elevation, slope, or distance from a water
body.
Unrealistic, of course, but this is a sophisticated ‘thought experiment’, and doesn’t need to be realistic.
2) They then run the model for 20 virtual years of ‘spin-up,’ and examine the steady state climates that result in each case.
Those results can be seen in their Figure 1. And what do the top panels of that figure show?
Desertland: water vapor increases because atmospheric residence times increase ~50%, due to reduced water retention on land, increased terrestrial temperatures, and those comparatively cloud-free skies you mentioned. As atmospheric water vapor increases, so does temperature: by about 2.5 C over land, but more than 3 C over the ocean. (The opposite happens for Swampland.)
So, what we have is a great demonstration of precisely the water vapor feedback: more water vapor in the atmosphere means more warming. So, no challenge in Lague (2023) to the water vapor feedback. On the contrary, their results rely on that phenomenon.
So, what about your “fear”? Specifically, that:
…we could arrive at hot continents with lot of water vapour on a clear sky thereabove, as described in Lagues “desert land” scenario. And, contrary to the results achieved by Lague 2023 which do not suggest any dramatic change in precipitation, I am afraid that the situation of “continental heat islands” might in fact result in a significant decrease of terrestrial precipitation, and in real desertification of entire continents.
Well, we’re already achieving something of the first effect by radiative forcing: while precipitation patterns are complex, and trends can be either positive or negative in different locations, we certainly do seem to be seeing a robust intensification of the hydrological cycle–both more intense precipitation, and enhanced evaporation.
However, with regard to the second concern you express, why would you expect that anything we could or will do could approach the state of the terrestrial surface prescribed in Lague? You seem to suggest, without quite saying, that you think some sort of runaway feedback process leading to that result could be possible. But what might that process be? I can’t imagine one, to speak only for myself. Yes, we can make city surfaces largely impermeable, fill or drain wetlands, and channelize rivers, and none of that is hydrologically good. But it doesn’t create Desertland–or Arrakis–on a continental scale, and it doesn’t by itself propagate. I really think you can relax a bit about land use, or at least the global magnitude of its effects, and perhaps worry a bit more about the radiative forcing issue, which is what really seems to be driving change today.
Davidsays
Kevin, your 30 Aug 2:52 pm reply to Tomáš was excellent.
JCMsays
“Yes, we can make city surfaces largely impermeable, fill or drain wetlands, and channelize rivers, and none of that is hydrologically good.”
precisely. Today, landscapes are impaired 40% compared to nature.
Repeated arguments by assertion which place humanity as insignificant demonstrate nothing. Those who make such claims might believe they’re presenting a real argument, but they actually offer nothing.
In reality, CMIP6 has no relation to ERA5L, lapse rate, nor TOA SW and LW observation whatsoever. They do not match at all.
No amount of total nonsense assertion provides any value on these pages whatsoever. Extreme desiccation of landscape warms climates, enhances SW absorption, and intensifies warming even more through WV feedbacks. Are y’all even being serious? It’s insane.
Unfortunately, I do not understand your interpretation of the Figure 1 in the cited article.
a) You speak about water vapour increase, however, Figures 1c and 1d show latent heat flux development of the tested models in time. Could you clarify?
b) You ascribe the course of the depicted time curves to the water vapour feedback, although there is no such commentary accompanying Fig. 1. The discussion of results provided by authors is, however, based mostly on results shown in Fidures 3 to 9, and seems to give a more complex picture, I think.
c) Figures 3 to 9 depict differences between swamp land and desert land. I have not noted any other reference system throughout the article. Could you specify where you found the information that in the desert land, water vapour concentration increased commensurately to the water vapour residence time increase which is about 50 %? What was the baseline for this estimation?
I think that I understand the view defended by our opponents:
There is hardly any reliable evidence that human activities during anthropocene led to continental desiccation. Although there may be hints from your practical observations of nature, it appears that there are no reliable precipitation records longer than ca 100 years, nor proxy data that could replace them.
Furthermore, it appears that there are no studies yet that tried to find out by computational modelling if (and if so, how) precipitation distribution between land and ocean could have changed as a result of human activities in the preindustrial era.
I am afraid that we have to wait and hope that such methods and/or studies emerge soon. Until it happens, our concerns that anthropogenic interferences with terrestrial hydrology might have contributed to climate changes observed during anthropocene, including the industrial era, will be taken as mere unsupported speculations.
in this context – degradation, desiccation, desertification, destruction, depletion of natural capital, erosion, or whatever you prefer – this represents the capacity for ecologies to maintain consistent moisture levels.
Although monitoring is extremely scarce and diminishing, climate science offers the opportunity to deduce these effects through its focus on the atmosphere. One approach is to critically examine and compare CMIP, which primarily emphasizes atmospheric radiative forcing and fluid Earth dynamics, against other sources of information and intermodel consistency.
Recall, climate science is no longer a study of the physics of the atmosphere and oceans, but also the ecology of Earth. This is the promise of Earth system science: to transcend disciplines to enable study of the interacting physics, chemistry, and biology of the planet. There is a real concern that trace gas enthusiasts will try to define the ecology of the Earth system by monopolizing so-called Earth System models.
On model consistency –
terrestrial latent heat flux varies widely across CMIP ESMs, from 35 to 65 W m-2. This significant variation suggests that the ensemble is ill-suited to detect perturbations on the order of 2-4 W m-2. Nevertheless, CMIP is often cited as evidence that large-scale land degradation has minimal biogeophysical impact on climates.
Furthermore, the change in carbon cycling through land is not known better than a range of zero (0) GtC to over 300 GtC in the recent decades across ESMs. Since changes in terrestrial organic carbon are closely linked to moisture stability, it’s almost impossible to draw meaningful conclusions about the impact of land degradation based on CMIP information. Yet this is often done.
Comparing to other information –
as previously discussed, reanalysis products deduce a decrease of ET over the recent decades according to the rigid requirements of simulating atmospheric states. In contrast, CMIP suspects a relentless increase of ET through it’s unconstrained scheme. Given that continents are inherently moisture-limited – a critical factor in their faster warming rate compared to oceans – a fair bit of caution should be used when drawing conclusions using the products of ESMs. Remember, a healthy soil is the wilderness beneath our feet. ESMs have nothing at all to say about that.
Additionally, in a paper you previously shared, it was demonstrated how the lapse rate effect is changing with the incorrect sign in CMIP compared to observed reality. Other works, including Schmidt’s 2023 CERESMIP-related paper, highlight significant discrepancies at the top of the atmosphere (TOA), particularly the unusual decrease in shortwave radiation (SW-out). Today, the Earth’s energy imbalance (EEI) is deviating outside almost all CMIP members and scenarios.
It’s worthwhile to re-consider the ecological aspects of ESMs when a wide variety indicators each suggest similar biases and unknowns related to biogeophysical effects. This input, supported by a variety of literature over many threads, goes well beyond mere assertions.
cheers
Barton Paul Levensonsays
TK: , our concerns that anthropogenic interferences with terrestrial hydrology might have contributed to climate changes observed during anthropocene, including the industrial era, will be taken as mere unsupported speculations.
BPL: Climate scientists found decades ago that land use was important to global warming. It is, however, a minor effect compared to that of greenhouse gases. The idea that it is being ignored is not true; please read the IPCC reports.
While the 1920s the 1950s and the 1970s and 1980s were the Age of Idiot Millionaires.
You think politics and the media wasn’t manipulated and BS back then?
The people may have changed, the issues might appear a little different, but nothing has changed here. The elites of America have been extreme belligerents and a dire threat to the world and humanity for well over 100 years already. Be they a Howard Hughes type or a news / media owner or a funder of elected officials. The Climate issue is the least of your problems in America. One of a hundred symptoms that are now out of control and impacting the entire world negatively.
Myopia affects people in both time and place.
Piotrsays
Sabine: “ While the 1920s the 1950s and the 1970s and 1980s were the Age of Idiot Millionaires”
Equivalence fallacy. First, in the 1920s-1950s even science didn’t know much about AGW.
Even 1970s-1980s both scientific understanding and public awareness of the AGW are nowhere those today.
Second, the Idiot Millionaires of the 1970s-80s, held less money and therefore less power, than the todays Idiot Billionaires:
– ” the share of wealth held by the top 1 % from 30 % in 1989 to 39 % in 2016, while the share held by the bottom 90% fell from 33 %to 23 %.”
– “the gap between the richest and the poorest in the U.S. more than doubled between 1982 and 2016.”
So no – it’s not the same.
Secular Animistsays
With all due respect your reply is boilerplate rhetoric devoid of any actual content, beginning with telling me what I think, and concluding with a generic insult that has exactly nothing to do with anything I have ever written or posted here. It’s a textbook example of pointless trolling.
Susan Andersonsays
Thank you, precisely correct.
Axe grinding, hypocritical intolerance all too often to the fore, as finding people to blame is so much easier than doing something real to make things better.
We have one job, to do the best we can with what we are given. [me: guilty as charged]
Piotrsays
Secular Animist to Sabine: “ your reply is boilerplate rhetoric devoid of any actual content, beginning with telling me what I think, and concluding with a generic insult that has exactly nothing to do with anything I have ever written or posted here”
Precisely. And quite representative of the “fundamentalists” here – Sabine, Ned Kelly, and to an extent – Geoff Miell or Killian:
1. despite little or no background in climate science, or because of that – are full of contempt toward climate science and scientists (Sabine: “none of the [Science and Scientists] should be trusted or believed “)
2. the reason for that – if the top scientists in the world failed to see what I, a lay person, did, then I must be really, really, smart.
3. they may use a scientist (say, Hansen) but only if they can cherry-pick their words to present as the confirmation of their narrative (“I have been telling you that for years, but you never listen“)
4, they are fundamentalists: either you are with them or against the truth
5. they are maximalists – it’s “all or nothing”; for them “the good is the enemy of [their] perfect”
6. by setting the goal impossibly high (nothing short of a complete change of the current social structure and economy, and altering human nature) they assure failure by breeding resignation and apathy: “since there is no way to get there – I may just as well give up, enjoy things while I can, and “After us – Deluge!”.
7. because of that, they often end up in bed with … deniers – because their results are the same – the apathy towards getting away from the fossil fuels
8. “ Les extrèmes touchant – while she has a seething contempt toward scientists “(none of the [Science and Scientists] should be trusted or believed“) Sabine goes all gaga over our (“anything but GHGs”) denier, JCM:
JCM blames “ the planet’s land degradation and loss of native ecologies” on “ artificial fixation and overemphasizing [the role of GHGs in global T changes]”
Sabine enchanted: – “JCM , What you say is great to hear and it has the ring of truth.
– To JCM. I think you are an excellent communicator and writer. Your quality insights, clear communication and knowledge are really wasted here on RC.
and fiercely protective: To JCM: Kudos! It’s unfortunate the phoneys and unhinged extremists are everywhere.
-+ Imho you deserve much better. t”
And their ignorance walks hand in hand with their arrogant conviction of being right even about things they know nothing about:
Sabine “ fair and targeted rational legislation and regulation within a Socialist market economy such as operates in China and Russia where the People come first ”
The tens of millions of the “People” who perished in “the People come first” Soviet Union and Communist China, might beg to differ with Sabine and her glorification of their killers.
Mal Adaptedsays
Piotr:
“8. “ Les extrèmes touchant – while she has a seething contempt toward scientists “(none of the [Science and Scientists] should be trusted or believed“) Sabine goes all gaga over our (“anything but GHGs”) denier, JCM:”
I just want to make sure you know that it was the video posted by Sabine Hossenfelder, who commented only once, that’s the source of “none of the [Science and Scientists] should be trusted or believed” quote by multi-posting, singly-named Sabine. I vehemently agree with your comment otherwise.
I, for one, think Dr. Hossenfelder is a skillful but problematic science communicator. With a career as a physicist, she’s uncommonly capable of understanding the physical science behind the consensus of climate-focussed scientists for rapid anthropogenic global warming. I get that she’s convinced by the data that the upward trend of GMST has departed from the more linear slope of the late 20th century, which means the ramifying impacts of warming are ahead of earlier projections. Yet her claim not to trust or believe unspecified scientists is disingenuous, because she stands on the shoulders of giants in her own discipline. Her warnings sound a little paranoid, and are forthrightly arrogant. [G]get back to Logic and the actual Data is all well and good, but Google Galileos rarely have the training and discipline to distinguish truth from deliberate deception, and are all too easily led astray by specious denialism! This is where scientific metaliteracy really makes a difference.
Her video isn’t denialism, to be sure. Her claim not to trust scientists doesn’t mean she thinks they’re exaggerating climate change for some mysterious agenda. She does trust the 200-year history of accumulating, verifiable evidence supporting the scientific consensus that global warming is happening and it’s anthropogenic. But she’s frustrated with scientific reticence and the principle of least drama, because she thinks climate experts should be speaking to decision makers and the public with greater urgency than they have been. I, for one, believe the principle of least drama is central to sustaining science’s epistemic authority, and the whole scientific profession loses by this professional scientist’s glib distrust. And while her suggestion that some scientists are motivated by the quest for grant money may seem reasonable to laypeople, she omits the fact that the majority of the scientists contributing to the consensus can just as easily do research without political consequences. Then there’s her implied false equivalency with denialists directly supported by carbon capital. Pretty freakin’ outrageous, really!.
IMHO anthropogenic climate change is already sufficiently urgent that scientists shouting greater alarm isn’t going to bring many voters along sooner. Dr. Hossenfelder is entitled to her dramatic opinion, and I think she’s pretty sly with the confident alarmism in her videos, but I speak only for myself.
Sabine H is good friends with Tim Palmer, he the Oxford climate physicist who recently published a book on the science of uncertainty called “The Primacy of Doubt”. Palmer is heavy into chaos, which is not a great prospect for prediction, but also associated with ECMWF . Haven’t read the book yet, but perusing it, he has some odd ideas on scientific computing — a la errors in numerics due to low-power quiescent-point digital circuitry that may help with climate simulations that he says can consume “10 of megawatts” of power per supercomputer. That gets to my comment up in the thread (search for “100 MEGA watts of power”). Yet, bizarre that he thinks errors in digital computers are benign, and that he doesn’t comprehend that there are parity checks, etc that nip the errors in the bud in any case. Could look into fuzzy logic instead, or NN even.
Desperately need a breakthrough here as throwing more computing cycles at a problem similar to climate dynamics rarely solves anything. I should rewatch the YouTube video of Tim and Sabine discussing climate science topics. Perhaps her outlook is swayed by Tim Palmer’s views.
Susan Andersonsays
Mal A (and others) Due to layering, I can’t reply directly.
Please note the ‘sabine’ here is not Sabine Hossenfelder. SH is a skilled communicator whose perspective, while it can be a mite (only a mite) annoying, never departs far from evidence and real science. In fact, she can be quite good, though when she wades into climate science she doesn’t quite get how engaged and distracting the verbal wars about climate can be, and how hard people like our hosts have worked to dispel the fog of ignorance; her efforts come across as more naive than wrong.
The rest of you have produced reams and reams of argument which make it nearly impossible to find the nuggets of value amongst all the dross.
Piotrsays
Mal – “ I just want to make sure you know that it was the video posted by Sabine Hossenfelder,
Yes, I know. This is why I was directing my 8 points to “our” Sabine – if you promote somebody’s else claims, then they represent your views, as well as those of the author.
Some of these points obviously do not apply to Sabine H. – obviously she is not attacking science from the position of ignorance (pp. 1-3), I don’t know whether she went all gaga over a specific denier, the way our Sabine went over JCM (so no p. 8 either) – nor she is responsible for our Sabine’s that the Communism in Russia and China, responsible for killing 10s of millions of people, are systems “where the People come first ”
That said Sabine H. “none of the [Science and Scientists] should be trusted or believed” combined with her use of half-truth and false equivalency between scientists and the deniers – suggest that p.4-7 do apply to her too:
==
4, they are fundamentalists: either you are with them or against the truth
5. they are maximalists – it’s “all or nothing”; for them “the good is the enemy of [their] perfect”
6. by setting the goal impossibly high (nothing short of a complete change of the current social structure and economy, and altering human nature) they assure failure by breeding resignation and apathy: “since there is no way to get there – I may just as well give up, enjoy things while I can, and “After us – Deluge!”.
7. because of that, they often end up in bed with … deniers – because their results are the same – the apathy towards getting away from the fossil fuels
====
Mal: Her video isn’t denialism, to be sure
That’s what my pp. 4-7 are about – you don’t have to set out to write a denialist piece to have your opinions help the denialists. The road to hell is paved with good intentions.
Mal: And while her suggestion that some scientists are motivated by the quest for grant money may seem reasonable to laypeople, she omits the fact that the majority of the scientists contributing to the consensus can just as easily do research without political consequences. Then there’s her implied false equivalency with denialists directly supported by carbon capital
This argument is straight from the denier’s writing guidelines – and you pointed to some of the problems – I would add that in most countries the research in government institutions is not funded from external grants, in fact – if anything, during Trump administration or in Russia – Gavin’s position would have been much more secure if he were denying the human cause of climate change.
Furthermore, if follw Sabine H. in her claim that scientists are corrupt – then they must be also idiots for going after pennies from the stingy government coffers, instead for billions available from the fossil fuel industrial complex: if Gavin could convincingly argue that the increase in GHGs is not the main cause of the climate change oil multinationals, Russia and Saudi Arabia would pay him his weight in gold – what’s $ 8 mln (assuming conservatively 100 kg of Gavin) reward compared to the TRILLIONS of dollars in oil profits on the line – you couldn’t dream of a better return on investment.
Sp much for the implied equivalency of climate scientists with the deniers funded by the fossil fuel interests and/or petro-states.
—
P.S. I wonder – has Sabine Hossenfelder included herself among the “none of the [Science and Scientists] should be trusted or believed “ – or the insinuation that scientist betray their ethics and instead prostitute themselves for grant money – applies only to OTHERS?
Mal Adaptedsays
Piotr:
Furthermore, if follw Sabine H. in her claim that scientists are corrupt – then they must be also idiots for going after pennies from the stingy government coffers, instead for billions available from the fossil fuel industrial complex: if Gavin could convincingly argue that the increase in GHGs is not the main cause of the climate change oil multinationals, Russia and Saudi Arabia would pay him his weight in gold – what’s $ 8 mln (assuming conservatively 100 kg of Gavin) reward compared to the TRILLIONS of dollars in oil profits on the line – you couldn’t dream of a better return on investment.
Sp much for the implied equivalency of climate scientists with the deniers funded by the fossil fuel interests and/or petro-states.
Whatever you do, do not watch or listen to what Sabine says. 10 minutes is far too much a waste of your precious time when it’s far better spent attacking climate denying tilting windmills and making it all up as you go. Trump Speak seems to have taken over the whole climate science community here where Facts Data Reason and Logic no longer are needed.
Do a Trump and say whatever pops into your head instead. Weird. The end times are definitely upon us – the people going mad was one of the signs apparently
And definitely do not watch to the end. She is clearly an ‘evil climate science denier shill paid for by the fossil fuels industry and the UK GWPF. I think you should all report her to YouTube and get her Cancelled forthwith. The Biden Administration to Sanction her and ban her from traveling and spreading her evil ways.
Some one should be nominating this site for the annual 2024 Skeptics Anonymous Award
Mal Adaptedsays
Susan:
Mal A (and others) Due to layering, I can’t reply directly.
…
The rest of you have produced reams and reams of argument which make it nearly impossible to find the nuggets of value amongst all the dross.
Aw, Susan, now I feel singled out. I’ll own my dross, but do you really feel that way about Piotr, Radge, Kevin, et al., and even yourself? If so, I’ll try not to take it personally!
We’ve talked about this. “Unforced Variation” includes forced responses to unforced variations of ill-informed scientific arguments and ill-conceived policy proposals. Anyone can simply scroll past the dross, and someone else can be counted on to pick out the rare nuggets and comment on them, whereupon one can go back to the original dross. Verbose challenges to any bad idea, not just outright climate-change denialism, are in the class of forced responses! Since that bi-monthly thread went away some time ago, we climate-science proponents have only this one to satisfy our personal joneses for dialogue.
Nonetheless, your plea for smaller reams of argument is well taken! I, for one, usually reach a point where I simply stop responding to further provocation by a tiresome source. There’s no reason to, when we’re all invisible, virtual identities, and physical violence isn’t a threat even for those who post under their real-life names (though cyber attacks might be, which is why I don’t). IMHO, the most satisfying response to sea-lions is to leave them wondering where you went!
Which reminds me: Bok made some constructive contributions last month, which can be revisited at will on that archived thread. He made several more good comments this month, but all of them are now missing. WTF? The mystery deepens. While my sympathies are with the harried moderators, I do wish they’d enlighten us!
Mal Adaptedsays
Paul Pukite:
Sabine H is good friends with Tim Palmer, he the Oxford climate physicist who recently published a book on the science of uncertainty called “The Primacy of Doubt”. Palmer is heavy into chaos, which is not a great prospect for prediction, but also associated with ECMWF . Haven’t read the book yet, but perusing it, he has some odd ideas on scientific computing — a la errors in numerics due to low-power quiescent-point digital circuitry that may help with climate simulations that he says can consume “10 of megawatts” of power per supercomputer.
Heh. Paul will recall “David Young”, a glib, confident denialist who showed up here five years ago. Young was eager to flaunt an opinion piece in PNAS by Tim Palmer and Bjorn Stevens, that he thought supported his claim that the CMIP ensembles used by the IPCC weren’t “fit for purpose”. Hilarity ensued, as others of us read the PNAS Perspective item and found it didn’t say what Mr. Young thought it did. Indeed the authors took pains to assure us they were confident (within published limits) in the GCMs consulted by the IPCC, and warned of those who “misrepresent doubt about anything to insinuate doubt about everything“. The piece was really about the need for models that make useful projections of local and regional climate change, as an aide to policy makers at less-than-global scales. The authors’ take-home message was a plea for funding of more computing power, to run higher-resolution, regional-scale simulations. Most of us were for that, of course, but agreed that global scale models were already plenty fit to inform the urgency of collective decarbonization.
Based on clues in his further comments, it seemed David Young’s denialism resulted from his ideological fear of collective action. He told himself climate change was a liberal preoccupation, merely a stick to beat rich people with. Models? Pfft! Scientists are all liberals committed to a collectivist agenda, and grasping for grants. And the decades long public record of propaganda and undue influence by carbon capitalists on the US government, in order to thwart collective intervention in their profit streams, is manufactured. Come to think of it, I haven’t seen Mr. Young here since then! I might have had something to do with that, in concert with his other antagonists here. No regrets.
Lastly: if it wasn’t already clear, I respect and admire Sabine Hossenfelder. I think she’s a highly effective science communicator, and clever about it. She may help US voters build a secure majority for federal decarbonization policy. I wish she’d go a little easier on climate scientists, who really aren’t in it for the grant money, and are constrained to the principle of least drama by formal training and peer discipline. But I see nothing wrong with emphasizing the upper tail of their uncertainty, if it strengthens public resolve to cap the warming collectively. As GCMs grow more sophisticated, climate realists should continue to defend modal projections regardless. IMHO, they are already quite alarming enough!
“recall “David Young”, a glib, confident denialist “
I do recall Young, who is an aerodynamics PhD at Boeing. His main concern was the pointlessness of trying to do fluid dynamics predictions, as his experience indicates that it all goes to turbulent chaotic flow (as in the flow over a wing, see here). He was also politically very conservative, which was likely the agenda he was trying to push,
OTOH, I don’t believe that ocean and atmospheric dynamics are chaotic and necessarily turbulent at larger scales. Or at least I don’t think anything has been verified one way or another, which means it is still worth researching. Two ideas to consider here (1) the concept of the “inverse energy cascade”, whereby smaller waves will feed larger waves, and thus reverse the direction from ever smaller scales of turbulence to something potentially more ordered, such as standing waves, and (2) external forcing as a means to overcome chaotic tendencies. Too many characteristics of large-scale climate behaviors such as ENSO show order rather than chaos, so the research focus should not be to give up as David Young would suggest everyone do. That’s the typical authoritarian style that seems shared among the political right. Would have appreciated having a scientific/technical discussion with Young, but that rarely turns out positive when politics is the overriding agenda.
Mal Adaptedsays
Paul:
Would have appreciated having a scientific/technical discussion with Young, but that rarely turns out positive when politics is the overriding agenda.
Yep. As my favorite repentant ex-Libertarian professional disinformer Jerry Taylor said:
Ideology = Motivated Cognition
In an interview, Taylor described how he came to realize he’d been peddling motivated denial, saying:
Jon [his friend Jonathan Adler] wrote a very interesting paper in which he argued that even if the skeptic narratives are correct, the old narratives I was telling wasn’t an argument against climate action. Just because the costs and the benefits are more or less going to be a wash, he said, that doesn’t mean that the losers in climate change are just going to have to suck it up so Exxon and Koch Industries can make a good chunk of money.
…
I regret a lot of it. I wish I had taken more care and done more due diligence on the arguments I had been forwarding.
Taylor turned out to be a genuine skeptic after all. Too bad there aren’t more like him.
Nigeljsays
Elon Musk is on record as saying climate change is one of humanities main problems and we need a carbon tax. Now hes flip flopped into a climate denier and fossil fuels proponent. Perhaps hes gone crazy and embracerd idiocy for whatever reason. However I suspect hes being nice to Trump and agreeing with Trumps climate denialism, hoping for a subsidy for his Tesla EV company if Trump is elected and to generally get Trumps support promoting EV’s.. Either way, his statements on climate are very badly informed.
I’m not sure he’s become an actual denier–there was a moment, reportedly, during the Trump interview where he tried to steer the latter toward accepting that there is actually a climate problem. Of course, it was useless.
And as long as he works to get Trump elected, what Musk actually thinks about climate is pretty irrelevant. It does seem as if his contempt for ordinary people, emphatically including his own workers, and his own sense of entitlement are what primarily drive his choices now.
Russellsays
Heinz, Pritzker, Putin, Turner, the list goes on and on
Barry E Finchsays
“The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic”. Well now you are going ambiguous. Is “form of average” an average of the SLR over a fixed doubling time, or some average doubling time? You are nothing if not slippery. To the sensible bloke back then few months ago (you are buried in my notes) I had intended to pin that SLR curve though I’m quite sure that its quadratic (NOT exponential) function pins at the centre month, not the start or end. But that’s a winter thing because I don’t bicycle in winter any more, the road ice is too much.
Sabinesays
While Americans remain extremist in their biased incomprehensible political views and take every criticism or valid comment personally and then get all emotional about any objective observations of their dire straits and dysfunctions and make believe political and economic self-fantasises, the Chinese simply get on with it, well planned, practical and effective and logical: so ho hum they’re boring. It’s what success looks like – but it still will not stop global warming or slow it down or protect ecosystem destruction:
NEW RENEWABLE TARGETS: Regulators published provincial targets for 2024-25 under China’s renewable portfolio standards (RPS) on 2 August, reported China Power. The targets, for the renewable share of electricity supply, increased by more than 3 percentage points year-on-year in most provinces, according to analysis published by financial outlet Yicai, “compared with a 1 to 2 points jump in previous years”.
UPGRADING THE SYSTEM: BJX News reported that China has issued a plan to upgrade its power system to “promote the construction of a new type of power system” between now and 2027. The outlet said the new system should be “safe, stable, cost-effective, flexible” and support the addition of more “clean and low-carbon” resources. A “key effect” of the plan, according to the National Energy Administration, is to improve the transmission of renewable energy from the remote desert bases to cities “at a large scale”, added the outlet.
SOLAR SURGE: Elsewhere, BJX News reported that China added 134 gigawatts (GW) of new renewable capacity in the first six months of 2024, according to the National Energy Administration (NEA) – an increase of 24% year-on-year. It added that solar made up 102GW of the total. (Total US solar capacity stood at 139GW at the end of 2023.)
‘UPHEAVAL’: China’s domestic solar industry is in “upheaval” with wholesale prices falling by another 25% so far this year, after falling by almost half in 2023, the New York Times reported. It quoted Frank Haugwitz, a solar industry consultant, saying efforts by the Chinese government to rein in the industry’s expansion have been “too small to reduce China’s overcapacity”. Bloomberg said that an increasing number of Chinese solar manufacturers “are falling into restructuring or bankruptcy”, adding that “while bigger players like Longi have so far survived billions of yuan in losses by imposing production halts and layoffs, smaller companies have fewer ways to plug financial gaps”.
‘SEVERE OVERCAPACITY’: In a meeting of China’s Politburo at the end of July, state-run newspaper China Daily said, president Xi Jinping called for “strengthening industry self-regulation and preventing ‘involutional’ vicious competition”, adding that China should “strengthen the market mechanisms” to help with “inefficient production capacity”. The outlet did not report that any particular sectors were named during the meeting. Several days earlier, Bloomberg stated that Wang Bohua, head of the China Photovoltaic Industry Association, had called for “struggling solar manufacturers [to be pushed] to exit the market as soon as possible to reduce severe overcapacity”.
The share of sales of “new energy vehicles” (NEVs) 51.1% – which includes both battery electric vehicles and plug-in hybrids – in China in July, according to the China Passenger Car Association. The trade body added that NEV performance beat manufacturers’ expectations, which it attributed to a trade-in policy encouraging consumers to replace old cars.
“The timeline here indicates policymakers still only aim to peak emissions by 2030, despite the clear likelihood that emissions will…peak much sooner,” Yao Zhe, global policy analyst for Greenpeace East Asia, said in a statement, adding that this shows China is still “underpromising”.
Li told Carbon Brief:
“This is the Chinese government rolling up its sleeves and trying to make quite an important switch…Folks have been advocating for China to really reduce its emissions in absolute terms for almost two decades. This is the mechanics of how this will happen – them actually making this switch and trying to make sure this is done in the right way by, for example, disaggregating [targets] to the local level, getting the private sector involved and trying to build up the carbon accounting system from the bottom up.”
Yao said Greenpeace expects that China’s next NDC will include a carbon emission reduction goal for 2035.
Li told Carbon Brief that China’s international pledge will then drive domestic targets, due to “how the timeline works”. He added: “The NDC [target] for 2035 has to be communicated in 2025, [looking] 10 years into the future…The job of the five-year plans for the next two five-year periods [will then be] to align with that international pledge.”
Not very coherent, anti-American bias aside. You tell us that “China is what success looks like,” then devote your two meatiest paragraphs to “upheaval” and “severe overcapacity”.
You are correct that China is the primary driver of the global energy transition, however. Kudos for the progress they have made. (We’ll see if they peak emissions this year or next, as some analysts project–but it seems very likely to happen before the promised date of 2030.)
But their society under Xi has other issues to address–xenophobia, gender inequality, territorial ambition, weak rule of law, and authoritarian rule., to name a few.
Peterbestyville@gmail.comsays
1 in 3 cars sold globally are in China. The electric vehicle revolution is taking place there so for those who are a technology revolution to mitigate emissions then China is the leader.
Politically and economically Europe and the USA are concerned so have put in tariffs/sanctions to make them expensive.
So China has the revolution tech but the wests worry means it’s a slow process.
We need longer to adjust or do we expect to buy electric western build vehicles
Nigeljsays
Sabine says: “While Americans remain extremist in their biased incomprehensible political views and take every criticism or valid comment personally and then get all emotional about any objective observations of their dire straits and dysfunctions and make believe political and economic self-fantasises, the Chinese simply get on with it, well planned, practical and effective and logical: so ho hum they’re boring. It’s what success looks like – but it still will not stop global warming or slow it down or protect ecosystem destruction:”
I think you are trolling there and making some big evidence free assertions about renewables not even slowing down climate change. You come across as just as extremist as the people you call extremists. Its sad because some of your points about American politics are valid. A gentler approach would probably generate better discussion, and on a page like this its not necessary to make such inflammatory comments to get attention.
Anyway I would say the reason China “just gets on with it” (building renewable energy) is because China is a dictatorship and so when the government wants renewable energy thats what happens, regardless of what the public wants or thinks. Dictatorships can be efficient, but personally I do not want to live under a dictatorship, and especially one rather dismissive of human rights and Chinas living standards are well behind Americas. Not even the climate crisis is a good enough reason to adopt a dictatorship system.
The reason Americas climate action seems disorganised is because America is a democracy and so every 4 years you can get a new government that might cancel the climate projects of the last gavovernment. Its an unfortunate situation. New Zealand has gone through a period of infrastructure projetcs getting cancelled in a similar way. The main parties are now looking at forming a bipartisan agreement on major infrastructure projects.
And in a democracy governments are understandably more sensitive to what the public wants (some of the time anyway) and to lobby groups. They have to be if they want to be elected.
In America political support between the two big parties and presidential candidates seems to have been rather evenly split in recent times. This might be partly a feature of it having only two main parties. For example the UK and Australia have the conservatives, Labour and the liberal democrats, so there is more choice. The UK also have bigger swings in the support each party gets. In America party suppor is more fixed and tribal, with election outcomes decided by relatively small numbers of people. Im hugely simplifying but to make a point.
Americans are not likely to choose to have a dictatorship form of government. Of course its just possible that Trump goes completely crazy and makes himself a dictator, and the fools in the Supreme Court and GOP support him. Then people would find dictatorships dont always deliver the outcomes that are good for the environment,
Thats the reality whether we like it or not. Mal Adapted expressed it all very well namely if you want climate action in America its going to be an incremental thing, and the Democrats are strongest on climate action so vote democrats.
Thanks for the copy and paste. Thats interesting.
Sabinesays
to Nigelj
Is there a particular reason why you choose to talk down to me as if I’m your 5 year old granddaughter who knows nothing at all about the world or life? As opposed to someone who has a mature life long and broad knowledge of the world and my very own values and judgments about life. A person who knows and can judge for myself what is real and true versus what is false misguided or mindlessly distorted cultural political propaganda? You must have a reason surely: but you sound like a primary school teacher presenting the socially acceptable school policy.
Mal Adaptedsays
Sabine:
Is there a particular reason why you choose to talk down to me as if I’m your 5 year old granddaughter who knows nothing at all about the world or life? As opposed to someone who has a mature life long and broad knowledge of the world and my very own values and judgments about life. A person who knows and can judge for myself what is real and true versus what is false misguided or mindlessly distorted cultural political propaganda? You must have a reason surely: but you sound like a primary school teacher presenting the socially acceptable school policy.
Well, Sabine, I can’t speak for Nigel, but your reaction (mysteriously missing now) to David’s mention of ProPublica, in which you told us all we were naive dupes of fossil fuel funded propaganda, was justifiably criticized as arrogant and insult-filled, not that of a mature adult.
Neither was this (quoted in subsequent replies from regular commenters):
Fair and targeted rational legislation and regulation within a Socialist market economy such as operates in China and Russia where the People come first.
That’s definitely not the opinion of someone who has a long and broad knowledge of the world. Just sayin’!
jgnfldsays
China , yes, is extremely authoritarian. Yet in this case, the massive problems china has encountered from extreme level of coal burning caused such problems for the population that even the authoritarians became worried. Beijing was becoming well nigh uninhabitable when the new policies were initiated in 2014.. https://aqli.epic.uchicago.edu/country-spotlight/china/. It’s still bad: They are the 13th most polluted country in the world by some measures and measurably worse as a country than the most polluted regions of the USA.. But their trends on some measures–my link is to particulates and lifespan reduction–are positive, not negative, and by fairly significant margins..
They also saw/foresaw, I think, the economic potential of various green technologies in their competition with the West.
I don’t necessarily think the authoritarians did this out of the goodness of their hearts, Authoritarians tend to balk at actions that may see unrest at levels that would lead to their personal demises.
Mal Adaptedsays
Nigel, let me just say I’m impressed with your fairly deep understanding of US politics, apparently acquired remotely. I hope you’re right that Americans won’t choose a dictatorship, but I wonder what our founders would make of the current state of affairs. As always, we’re forced to choose between two evils, but it’s hard to imagine a greater evil than a Republican victory this fall, at least by comparison with the Democratic Party’s moderate, science-respecting platform. That approximately half the voters are planning to choose Trump, demonstrates our growing inability to rank the world’s evils. As many as half my fellow citizens appear to prefer comforting denial to inconvenient truth. Oh, my people!
Secular Animistsays
Nigelj wrote: “China is a dictatorship and so when the government wants renewable energy thats what happens”
It is not as simple as that. China is a dictatorship but “the government” is not a monolith. Indeed the government INCLUDES the Chinese fossil fuel industry which remains a powerful force in determining what exactly “the government wants” — as it does everywhere in the world regardless of the form of government.
Escobarsays
According to the prevailing resident ideology Carbon Brief has become a Communist insurgency, an anti-american supporter of authoritarian dictatorship of China, and should be labelled a foreign agent under the FARA Laws. Everything presented by Anika Patel must be all lies and propaganda then.
Mal Adaptedsays
Prevailing resident ideology? Nah. That was one commenter, singly named Sabine. Talk about a straw [wo]man!
I wouldn’t be completely surprised if there was a political correlation here, with the Chinese government heavily subsidising the sales. Chine has often previously lined up with Pakistan on ‘enemy of my enemy’ grounds. (And I’m not saying that a large quantity of renewable electricity in Pakistan isn’t a good thing!)
Barry E Finchsays
Nigelj 14 Aug 2024 at 4:15 PM “My recollection is that James Hansens findings are that above 2 degrees you kind of reach a tipping point where glaciers start to dramatically speed up their flow into the oceans”. My recollection is that Eric Rignot said 2 things “when a marine-terminating glacier’s ice shelf is gone it speeds up to 6-7 times its present” and another time with no explanation “a SLR of as much as almost 5m / century is possible” so I instantly applied my high mathematics skills same as “Geoff Miell” and calculated ((2,200+600)*5.5) * 100 / 360 = 4,280 mm / century from ice loss AFTER ALL THE ICE SHELVES ARE GONE. Throw in 200 mm / century for expansion and the insult and you got 4.5 metres per year after all ice shelves gone. I started studying ice shelves and got through about 40 of the glaciers on Greenland in 50 hours or so before losing interest and moving on. Also, Eric then confused me by stating later that grounding line retreat was far more important than ice shelf or no ice shelf. Still I suggest you could get a good working prediction by figuring out when each ice shelf will be gone so … Go For It because ….. I absolutely definitely NEVER will (can’t even understand my own hundreds of lines of references, notes and calcaultions about it from 2018). The “Geoff Miell” of course reliably brings a lazy nothingness (no study work) to the science table on this century, multi-century prediction topic, similar to a truly-awful, lazy “Paul Beckwith” bloke.
Barry E Finchsays
Tomáš Kalisz 14 Aug 2024 at 2:30 “global water vapour concentration increased … while concentration of greenhouse gases remained constant” is an impossible self contradiction unless it happened that CO2+CH4+O3+N2O concentration decreased by an amount equalling the H2O gas concentration increase.
In the article, the authors tested the influence of water availability for evaporation from the land on global climate. In this sense, it is understandable that they kept the atmospheric concentration of all non-condensing greenhouse gases in their model constant.
They found out that the “desert land” provided higher average water vapour concentration and lower global precipitation than the “swamp land”. It is an open access article, which you can read on
modelling the influence of land disctibution over the globe using an ISCA climate model that considers only water vapour but does not include clouds, they arrived at qualitatively different results.
Putting more land into tropical region (and thus decreasing water evaporation) in this case caused a decrease in global average air humidity and global climate cooling.
Personally, I assume that the model comprising clouds is more realistic than the previous one, however, I do not dare to assess if it is indeed realistic enough that the results are at least qualitatively correct (and that they perhaps will not reverse again if an even more sophisticated model is used instead). This was one of the reasons why I asked if there is another similarly directed study using a different model, and if a climate scientist could comment.
Greetings
Tomáš
Barry E Finchsays
JCM 13 Aug 2024 at 1:34 “trace gas reduction” S.B. “well-mixed greenhouse gas reduction”. Much as I dislike the “greenhouse” phrasing that somebody decided was best, we are stuck with it. If is mentioned “infrared-active gas” I expect >99% would think “Whaaaat?”
A critical aspect of terrestrial forcing is its coupling with large ocean reservoirs, which operate at their energy limit and supply moisture to the atmosphere at saturation. The ocean’s surface response is strictly energy-limited and follows the temperature-dependent equilibrium partitioning of turbulent flux.
Since others have provided no quantitative analysis – only unsupported, ideologically-driven, and overtly-biased hand-waving – I’ll reference the ongoing widely discussed idealized model. Using this model, temperature is linearly related to ET suppression at -0.16 mm/day/K, incorporating all feedbacks. Column water vapor increases by 1 mm/K. This idea is inconvenient for certain storylines so it seems to be rejected automatically.
Nevertheless, ERA5L is giving a trend ET -0.2 mm /yr for the recent 30 year climatology.
When integrated over 30 years, this equates to about -0.02 mm ET/day. The maths could be verified as there is some rounding happening.
With a coupled model temperature relation -0.16 mm/day/K, the 30-year change in ET in reanalysis corresponds to a climate response of about 0.13 K, or roughly 0.04 K per decade assuming equilibrium. Include plus and minus huge uncertainties.
Using the idealized ET suppression model and ERA5L data, we should expect a 30-year global increase in column water vapor of about 0.1 mm due to biogeophysical effects, in addition to the biogeochemical carbon cycle effect. This is why the shorthand trace gas distinction is convenient in this context.
The change in shortwave radiation (SW-in) is approximately 2 W/m2/K in equilibrium, due to the shortwave CRE feedback to ET suppression. The so-called “humidity paradox” could be explained by terrestrial moisture limitation combined with vast expanses of energy-limited ocean. This appears to be associated with greater energy flows through the system.
In the CMIP6 ensemble, standard radiative forcing is expected to cause (somehow) a huge stabilizing increase in terrestrial ET of about 0.3 mm/year. However, reanalysis shows a change -0.2 mm/year, a difference of -0.5 mm/year over the recent climatology, indicating the expected stabilization is missing. This difference equates to roughly 0.1C per decade and 0.3 mm of unaccounted column water vapor. Fluxcom yields a difference 0.6K/century. The effects under various sky conditions, both clear-greenhouse and cloudy-shithouse, are critical. But, it is all very uncertain.
The example provided is just one element from an idealized experiment where NCAR assisted to plug a simple land interface model with the CESM. Additional factors discussed in ecological climatology include various other changes as well.
Gordon Bonan’s work describes these processes conceptually: ecological destruction increases surface reflectance and reduces the energy available to drive the hydrological cycle. It decreases evapotranspiration and increases sensible heat flux, thus lowering humidity and potentially inhibiting cloud formation. It reduces surface roughness, limiting heat transfer between the biosphere and atmosphere, which may warm land surfaces and decrease convective overturning. It also diminishes biological ice condensation and precipitation nuclei, affecting the cloud and energy budget. The net effect of these changes is unknown, poorly monitored, and largely outside the scope of the UNFCCC.
Summaries of the climate science provided to policymakers typically offer only simplified accounts, such as the cooling effect of increased surface reflectance from ecological destruction, suggesting that it is offset by the trace gas effects of the missing carbon sink. It seems that because biogeophysical monitoring and inputs are not prioritized, they are treated as if they don’t exist. Meanwhile, CMIP/AMIP models still fail to adequately parameterize surface factors (e.g., vs ERA5), leading to poor reflections at TOA (e.g., CERESMIP).
Your explanations look as an excerpt from an article. Could you provide the reference, or is it a yet unpublished work (perhaps the article you mentined in your previous post?)?
Greetings
Tomáš
JCMsays
To Tomas,
the discussion combines elements from Kleidon’s “Working at the limit: a review of thermodynamics and optimality of the Earth system”, to Lague’s “Reduced terrestrial evaporation increases atmospheric water vapor by generating cloud feedbacks”, and various elements from Bonan’s research.
Specifically, the linear relationship of -0.16 mm/day/K for ET suppression was simply derived from Figure 4, panel (a) in https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1 by dividing the total change in mm/day for land by the total temperature change.
Recently, Clair Zarakas and collaborators, including Bonan, provided a comprehensive summary of land element parameter ranges and their significance in: “Land Processes Can Substantially Impact the Mean Climate State”.
Specific Key Points from Zarakas:
“Assumptions about land processes substantially impact mean state terrestrial temperature and precipitation.”
“Land parameters influence climate predominantly through changing evapotranspiration rather than through other mechanisms.”
“Warming driven by land processes activates different atmospheric feedbacks than radiatively-driven warming.” https://eartharxiv.org/repository/view/6605/
Additionally, it is the soil hydrology parameters, not the plant physiology change as observed from space, which dominate the influence:
“Three soil hydrology parameters – frac_sat_soil_dsl_init, d_max, and fff – had the largest impact on global mean temperature. Land surface temperature change in the land-only perturbed parameter ensembles (PPE) were generally much smaller than those in the coupled PPE, consistent with the fact that atmospheric feedbacks substantially amplify the land surface temperature response to changing land surface properties (Lague et al., 2019).”
“”While land modeling has substantially expanded beyond its initial scope of providing lower atmospheric boundary conditions into its own subdiscipline and research community, land models’ continued role as atmospheric boundary conditions means that a broader climate science community must engage with land processes (and uncertainty herein) in order to understand and model the physical climate system””
As you may have noticed, some contributors mistakenly believe that greenhouse climate politics and the CO2 problem encompass the entirety of global change science. This is totally false. An enriched understanding requires a broader view that appreciates the scope of this field, not merely what’s spoonfed in fancy promotional brochures. Historically, climate studies were part of Geography, integrated with systems and ecology. However, since the climate policy frameworks of the 1980s and 90s, certain barriers have emerged in academia, limiting the convergence of multidisciplinary research. This narrow perspective is often perpetuated by amateur enthusiasts and even some academic activists who naively assume that hydro-ecologies merely respond passively to atmospheric change. This view is not only misguided but also fundamentally wrong (despite their ongoing red-faced-steam-coming-out-of-the-ears objections). Some contributors also seem to fear that acknowledging the significant human impacts on global change and their relationship with climate dynamics might upend everything they believe to be true. This is also totally false.
The range of factors is documented in introductory climate texts, particularly those focused on the surface-atmosphere boundary layer. This I know for certain! It’s not controversial and these processes are essential in governing heat dynamics on Earth; it’s just rather not the focus of the narrow climate politics, newsmedia, public outreach, fashionable grants, awards, and television programs. However, I admit that when regional or global ESM biases emerge and influential people scratch their heads looking only at industrial aerosol or gas emission inputs I wonder what the heck it is they are thinking. I believe somehow the view of environmental change has been mishandled in such a way that it has been reduced to “pollution” which becomes ingrained in children for life. No amount of mathematical rigor or astrophysical brilliance seems to overcome this shortcoming.
That said, atmospheric pollution matters and it’s critically important to handle using globally prescribed targets. Additionally, profound ecological destruction and what we’ve done to landscapes must also be remedied. This can be handled in short-order using locally-oriented, diverse and well-understood solutions (don’t expect your favorite climate celebrities to know anything about that). Admittedly, this is messy and inconvenient from a global governance perspective; but, conditions can be improved quickly with localized, well-understood methods, offering benefits in a matter of years, not centuries.
Personally, I am somewhat sceptical about drawing quantitative conclusions from Lague 2023. I already wrote to Piotr that if we look e.g. on panel 3 in Figure 4, we see that the difference between the “desert land” and the “swamp land” in annual sum of precipitation, as predicted by the model used by authors, is remarkably small.
In deserts of the real Earth, lack of water available for evaporation seems to cause much more dramatic difference in precipitation patterns.
Greetings
Tomáš
Piotrsays
Tomas Kalisz. joining JCM in his attack on Lague et al 2023 they used before a proof of their claims:
In deserts of the real Earth, lack of water available for evaporation seems to cause much more dramatic difference in precipitation patterns
Only in the deserts of your brain, Mr. Kalisz. On the real Earth – we have such a thing as “wind” – hence the results of your own source that you both try now to disown.
JCMsays
Thank you Tomas, this is very interesting.
Consider that moisture cycling rates are influenced by both ecosystem characteristics and temperature.
For example, in today’s Earth, a desert ecosystem may exhibit ET rates of 0.5 to 4 mm/day, while a wetland might range from 5 to 15 mm/day, depending on its geographical location. This results in a global average difference of about 6 to 7 mm/day between wetlands and deserts. However, in the extreme scenario, this difference narrows significantly to just 1.3 mm/day when comparing a total swamp to a total desert (with ocean). That seems surprisingly small.
It’s important to consider the continuum of globally averaged temperatures depicted in the extreme scenario, in addition to ecological variation.
Comparing the 6 or 7 mm/day difference based on current ecological conditions in the mean climate state of today to a planet with a significantly different GSAT could be misleading. It’s only half the story.
Recall, increasing moisture availability is typically associated with decreasing temperatures. When examining the hydrological cycle, these factors tend to oppose eachother. Specifically, an optimum arises by riding at the intersection of moisture availability and energy limitation. As globally averaged temperature decreases, also the energy becomes more limited.
Therefore, a much cooler planet than today’s Earth is likely to exhibit a globally averaged ET difference between wetlands and deserts that is less than 6 or 7 mm/day. Conversely, a much warmer planet might show a greater difference. Imagine an oasis surrounded by desert – the oasis will exhibit significantly higher ET compared its surroundings. As GMST increases, so does this contrast.
While the moisture-dependent variation could be substantial, the mean change aligned with GMST may remain minimal due to the optimal balance between energy and moisture availability. For this reason I think it’s useful to digest Kleidon’s thermodynamic constraints framework.
A similar principle applies to ocean v land. As continental moisture becomes more limited and GSAT rises, the oceanic latent flux increases to match the new (increased) energy threshold. This establishes a new steady-state optimum with higher GMST and increased oceanic evaporation.
The ocean’s response is inversely related to changes in land ET. In the extreme CESM scenario, the ocean-land ratio is 0.43/-1.3, meaning that for each area-unit of moisture reduction on land, the ocean compensates with an increase of 0.3 due to higher air temperatures. The overall global difference in this new steady state reveals a global mean atmospheric moisture regime not drastically different from other steady states.
In summary, the global mean difference in atmospheric moisture dynamics when varying GSAT is minimized by the opposing factors of moisture availability and energy limitation. Under an extreme scenario in the CESM, with 8K temperature difference, the global mean change in latent flux is a mere 0.19 mm/day.
This compensation is illustrated in Figure 3, where dry continents see the ocean almost entirely compensating for the reduction by utilizing the increased energy availability. This is accomplished with a higher global mean temperature. The new steady-state precipitation patterns and wind anomalies are shown in Figure 12.
Finally, acknowledging your concerns, it’s important to note that, based on the experience of CMIP, other ESMs besides CESM are likely to exhibit significantly different responses.
I am fine with a small difference in global latent heat flux between the swamp land and desert land extreme scenarios.
What I see somewhat suspicious is a relatively small difference between land and ocean in both scenarios. Makarieva et all are afraid that anthropogenic disruptions in rain recycling over continents, caused by improper land use, might have caused, at least in some regions, a feedback loop that resulted in a complete desertification of an originally humid landscape.
I have no idea in which extent are mechanisms like rain recycling included in state-of-the-art climate models generally, and in the CESM used by Lague et al specifically.
This would be my question to climate modellers, if there was any willing to reply.
Greetings
Tomáš
JCMsays
Thank you Tomas,
I want to caution against interpreting the small relative mean change in mm/day as evidence for a lack of profound climate change. The results from CESM seem to imply a large SW cloud radiative response to changing properties of the landscape. This suggests a significant departure in variability of the moisture regime alongside changes in GMST.
I typically discuss this change in variability as increasing hydrological and temperature extremes. Switching from gentle daily rainfall to highly variable and infrequent precip is a profound climate change, despite this being obscured by smearing it into the avg mm/day in model summaries.
From a hydrological perspective, beyond the scope of Lague, a significant decrease in precipitation frequency combined with an increase in intensity with GMST accelerates desertification. This happens because catchments become less efficient due to saturation or infiltration excess flows, in addition to direct destabilization. This is the flipside relation of flood and drought – as rainfall is harvested less efficiently, this compounds erosion & desertification. The most extreme visualization is urban stormwater through concreted drains. Consider the downtown core of any metropolitan area as completely desertified.
Recognize additionally that from my hydrological and soils perspective we typically refer to desertification as specific to the soil properties themselves, not directly associated with the avg rainfall. That is: desertification = land degradation, increasing bulk density, loss of fertility, loss of soil organic matter, slowing or loss of nutrient cycling, loss of life.
Regarding Makarieva, early in my involvement here, Gavin Schmidt poo-poo’d discussions on her work, partly due to her unfounded criticism of model physics. After reconsideration, I believe current-generation models might actually capture these mechanisms given the right input. This is supported by Lague’s use of the CESM.
While I can’t speak for those designing complex process models for inclusion in CMIP, I understand that the goal is to minimize tweaking specific mechanisms. Instead, the focus is on setting boundary condition constraints, like initial optical thickness and surface parameterization, and letting the governing physical equations determine the outcomes in global circulation, temperature, and precipitation patterns.
More recently, Makarieva has been highlighting discrepancies between observations and models regarding the lapse rate and the expected lapse rate feedback. She notes that “current models assume that as the planet warms, the temperature lapse rate should slightly decrease, following the moist adiabat (the so-called lapse rate feedback, Sejas et al., 2021). While this is robust across models, observations indicate an increase in the lapse rate, especially over land, consistent with radiative forcing due to changing non-radiative fluxes, including those caused by land cover change.”
In my view, Makarieva’s point holds without needing to introduce new model physics; rather, it may be a critique of the largely unconstrained and unmonitored surface parameterization.
cheers
Piotrsays
JCM: the language sensitivity is understandable Barry – but, as previously discussed, it’s a shorthand to avoid misunderstandings
Your use of the “trace gases” has the goal OPPOSITE to avoiding misunderstanding:
First, the term is poorly defined – there is NO natural nor generally agreed upon definition of the word “trace” in the context of the greenhouse effect. In analytical chemistry, a trace element is “one whose average concentration of less than 100 parts per million (ppm).” By their definition – CO2 is NOT a trace compound – it doesn’t have and never had in the last couple bln years, conc. <100 ppm.
Second, the term is scientifically useless in the context of AGW – since almost all AGW is driven, directly or indirectly, by what you call “trace gasses” while the “non-trace gasses” do nothing (N2, O2) or are merely feedbacks – PASSIVE amplifiers of the effects of the “trace gases” – if we increase conc. of trace gases – water vapour would make the resulting warming larger, if we we decrease “trace gases” the water vapour would make the resulting cooling larger.
Therefore, water vapour is not a forcing, and as such won’t reduce the RELATIVE importance of “trace gasses” in driving AGW, quite the opposite – it makes the climate not less, but MORE sensitive to what we do to “trace gases” in the atmosphere.
Third – ironically, by being “trace amounts” – it is easier for humans to CHANGE them and thus alter their radiative forcing. Contrast this with water vapour – where natural fluxes are MASSIVE, and the residence time many orders of magnitude SMALLER than those of CO2 et al. – hence it would require “mindboggling” effort and money to change these massive natural fluxes in any significant way,
Fourth, the use of “trace gasses” to the general public is misleading – by implying that a “trace gas” can only have a “trace influence” on the climate. And the Occam razor suggest that it is YOUR reason for insisting on using this phrase – as part of the old deniers narrative “Anything but GHGs” – if the trace gases had influence corresponding to their (trace) concentration, then this would support your attack the climate science by blaming it for:
“ the planet’s land degradation and loss of native ecologies [due to] an artificial fixation and overemphasis on the outputs of trace gases ”. JCM
And promote your non-trace gas (water vapour) – as an viable alternative to the AGW mitigation INSTEAD of the “ artificial fixation and overemphasis on the outputs of trace gases“.
Piotrsays
Re: Barry E Finch Aug. 16 – I doubt you will convince JCM – he INSISTS on using “trace gases” for a very specific reason – to imply that “trace” gases have only “trace” importance to AGW.
He needs it to push an old denier narrative “anything but GHGs” – if the effect of “trace” gases are indeed “trace” too – then it is intellectual honest to call for a switch of the the research efforts and money from “trace” gases mitigation to gigantic (i.e. non-trace) geoengineering of the water cycle
And for a better effect, lets blame the climate science for:
“ the planet’s land degradation and loss of native ecologies [due to] an art
MA Rodger says
UAH has posted its TLT July anomaly as +0.85ºC, up on June’s +0.80ºC. This is also up on July 2023’s +0.64ºC, making UAH’s July 2024 TLT anomaly the hottest July on record.
Some SAT records may also manage to show July 2024 as ‘hottest on record’ but so far the re-analyses (CDAS and soon ERA5) are/will-be showing July with a higher anomaly than June’s but below July 2023.
[Response: This is a little interesting. We know that MSU TLT has a larger fingerprint from El Niño than the surface records (cf. 1998 etc.), and so this is evidence that the spikes seen in the surface records last summer/fall were not (wholly) driven by the emerging El Niño… – gavin]
Paul Pukite (@whut) says
Now is a good time to review the work of erstwhile chief scientist James Williams of NASA JPL on the strongest lunar forces. Plug those in and good things will happen in modeling El Nino,
https://gist.github.com/pukpr/e562138af3a9da937a3fb6955685c98f
As to the [comment}– the fact that UAH still shows a high temperature despite the El Nino winding down is the evidence?
Paul Pukite (@whut) says
Why the use of so much electrical power to solve climate models?
https://eos.org/research-spotlights/modeling-earth-systems-at-a-quintillion-calculations-per-second
This is a huge power addition due to the application of information technology. Everyone is grabbing a piece of the ever expanding pie:
https://www.utilitydive.com/news/exelon-pjm-capacity-auction-bge-talen-data-center/723163/
Quintillion calcs/sec burns lots of CPU cycles to predict climate, a slight +feedback to the climate change problem. Yet, if a modern CPU is 10-20 GigaFLOPS/watt, a Quintillion FLOPS computer would use 100 MEGA watts of power. So if a hairdryer is 1000 watts, this is 100,000 hair dryers using power in parallel. Substitute that many microwave ovens, vacuum cleaners operating for days at a time. That’s the context missing from the AGU article linked above.
Let’s see if we can compute smart and not hard, as with https://GeoEnergyMath.com.
Likely, breakthroughs will be in understanding the nonlinear fluid dynamics, not in wasting CPU cycles going down a path that leads to the wrong answer.
Paul Pukite (@whut) says
Regarding the recent ocean temperature extremes:
So, the scientific explanation is “weirdness”. In this case, weird is a euphemism for “we have no idea”. Related to the observation of the experimental scientist who exclaims: “I’ve never seen that before”.
As long as the jury is still out and weird is now under consideration, I will once again offer the nonlinear modulation of forcing which cross-validates indices such as ENSO and AMO. The formulation is weirdly unconventional but it does obey the primitive shallow-water wave equations used in modeling the ocean’s fluid dynamics. As with quantum mechanics or the theory of relativity, non-intuitive weirdness is a small price to pay for creating a correct model of observed behavior.
Paul Pukite (@whut) says
Consider quantum mechanics plus the extra non-linear weirdness of Fermi resonance, which in a recent paper by Wordsworth et al appears to be a significant factor in the GHG properties of CO2:
https://iopscience.iop.org/article/10.3847/PSJ/ad226d#psjad226ds4
CO2 is a linear molecule, so it does not have the strong GHG properties of the “bent” geometry of H2O. Yet, because of the stretching modes of the CO2, a pair of CO2 molecules can combine forces and induce a bending mode that would normally not get excited if the quantized sum of energies didn’t match so closely.
So, Fermi resonance is a phenomenon that occurs when two vibrational modes in a molecule are nearly degenerate (i.e., have similar energies) and interact strongly. This interaction can lead to a splitting of the energy levels and a redistribution of the intensities of the vibrational modes.
In the case of carbon dioxide (CO₂), Fermi resonance typically involves the interaction between the stretching modes and the bending modes. CO₂ has two primary stretching modes:
Symmetric Stretching Mode: Both C=O bonds stretch and compress in unison without changing the bond angle. This mode is generally inactive in infrared (IR) spectroscopy because it does not create a dipole moment.
Asymmetric Stretching Mode: One C=O bond stretches while the other compresses, changing the bond angle and creating a dipole moment, making this mode IR active.
In addition to these, CO₂ has a bending mode where the molecule bends out of its linear shape. (Here it will appear more like H2O)
Fermi resonance in CO₂ can occur between the first overtone of the bending mode and the asymmetric stretching mode. The bending mode has a fundamental frequency, and its overtone (second harmonic) can come close to the energy of the asymmetric stretch. When the energy levels of these two modes are close, the overtone of the bending mode and the stretching mode can “mix,” resulting in two new energy levels: one higher and one lower than the original energy levels.
This resonance causes a shift in the observed frequencies and an alteration in the intensities of the absorption bands in the IR spectrum. The Fermi resonance allows the bending mode to become IR active when it might not have been otherwise due to the quantized sum of energies aligning.
So when two CO₂ molecules interact, they can enhance this effect. The combined forces of the molecules can induce a bending mode that would normally not get excited if the quantized sum of energies didn’t match. This results in a coupling that redistributes the vibrational energy, leading to a Fermi resonance that can be observed spectroscopically. And the more the quantized energy levels, the more that a molecule can have a GHG effect by creating a sideband that exists within the IR spectrum .
No one really “understands” quantum mechanics, one just has to accept the arcane rules of quantized energy levels and structural symmetry, Same thing happens in fluid mechanics at a large scale. And once climate scientists look into the nonlinear interactions of waves, the sooner they will be able to model standing-wave phenomena of ENSO, and the sidebands that can occur from mixing constrained by the allowed wavenumber states within the oceanic waveguide.
David says
Re Paul Pukite’s 15 Aug 2024 10:43 AM posting, I came across the following article at Quantum Magazine on the recent paper by Wordsworth et al:
.
.
https://www.quantamagazine.org/physicists-pinpoint-the-quantum-origin-of-the-greenhouse-effect-20240807/
Paul Pukite (@whut) says
Much discussion about the Atlantic Ocean rapidly cooling recently, such as https://www.newscientist.com/article/2444394-part-of-the-atlantic-is-cooling-at-record-speed-and-nobody-knows-why/
The AMO (placeholder version) is still high in July (month #7, and previous 6 below)
1 1.07
2 1.16
3 1.19
4 1.13
5 1.37
6 1.38
7 1.32
https://pbs.twimg.com/media/GVNnSzuWcAAVxXb.jpg
Atlantic Nino index, a more equatorial measure, shows the dip in the chart below
https://pbs.twimg.com/media/GVrhW2gXMAUlRUg.jpg
That’s likely what’s rapidly cooling.
Shows the importance of the standing-wave nature of the oceanic indices. As the thermocline sloshes in subsurface depth, different parts of the ocean show different surface temperatures, indicating proximity to heat or cold.
The interesting aspect is the concurrent appearance of Pacific La Nina conditions with Atlantic Nina conditions. These are now in phase, much like the tropical instability waves (TIW) always appearing in the Pacific and Atlantic during Nina conditions. TIW are invariably 1100 kilometers in wavelength and show up because the cooler below-thermocline water approaches the surface and so is more highly delineated as the long-period tidal forces modulate the low-effective gravity interface.
Barlow is showing the Pacific TIW here https://x.com/MathewABarlow/status/1826623840598065313
Don Williams says
1) Re recent arguments that we can feed 10 billion people and hence can be indifferent to population growth, a recent article in Nature notes how large amounts of greenhouse gases are produced by the production of the synthetic fertilizers that modern agriculture uses in massive amounts. I.e., the creation of agriculture’s inputs are a problem, not just agriculture’s own emissions.
https://www.nature.com/articles/s41598-022-18773-w
2) Plus the last time I checked those massive farming machines don’t run on sunlight.
3) The US Midwest feeds much of the world — but the huge Ogallala Aquifer used for irrigation is being depleted — which will put us back into the Dust Bowl.
4) Good intentions are no substitute for knowing how the chainsaw works.
Secular Animist says
Don Williams wrote: “the last time I checked those massive farming machines don’t run on sunlight”
Tractors and other farm equipment can easily run on electricity generated by sunlight. Some reading for you:
https://www.monarchtractor.com/blog/electric-tractors-farming
https://springwise.com/innovation/agriculture-energy/solar-powered-micro-tractors-for-sub-saharan-africa/
Don Williams says
1) From your citation:
“According to a March 2024 news release by MarketsandMarkets™ the electric tractor market is projected to grow from USD 0.7 billion in 2024 to USD 3.4 billion by 2030.”
2) From https://www.mordorintelligence.com/industry-reports/tractors-market
“2024 tractor market: $84.8 bil – projected 2029 market: $114.5 bil )
3) Not only do electric tractors have (and will have) a very paltry market share, look at how electricity to fuel them is generated in the US Midwest. While wind has gained, much is still generated from natural gas and coal.
https://www.nytimes.com/interactive/2024/08/02/climate/electricity-generation-us-states.html
Kevin McKinney says
Don, you appear to be mixing apples with walnuts–a great combo for salads, but not comparisons. SA’s cite suggested exponential growth in the US electric tractor market, via a nearly 5-fold increase in 6-7 years; yours counters with a *global* market projection, which moreover is not broken down by technology. Thus, your claim that “electric tractors… will have… a very paltry market share” is unsupported. (Particularly since–if you believe both sources–the growth rate of electric tractors, in the US at least, is clearly much higher than the overall tractor market growth rate–that implies rapidly increasing market share for electrics.)
Can’t see your NYT source, as it’s paywalled, but just to highlight the “gains” of wind, the three states with the largest proportion of wind generation are Midwestern:
–Iowa, (81.75%)
–South Dakota (65.59%)
–Kansas (64.56%)
(Honorable mentions to NB (41.66%); ND (38.87%)–though most of the rest comes from coal–and MN (33.32%).)
(Source)
And maybe it’s worth mentioning that IL produces 54.15% from nuclear, and that both MN and MI have adopted 100% clean energy laws.
But that’s just a snapshot of today’s conditions: RE is gaining share by an exponential trend. Those state RE shares are going to be higher next year, and every year thereafter, for the simply reason that RE is now the rational economic choice in most instances.
We’ve frequently decried the inability of humans to cope well with exponential change rates,* which have made it difficult to understand the danger we face under climate change. But this likewise makes it difficult to appreciate the speed with which the energy transition is now happening.
*Over the longer term, the trend will not be an unbounded exponential one; it will follow something closer to the classic S-shaped ‘logistic curve.’ But we’re not there, yet; we’re now in the rapid acceleration phase.
Don Williams says
1) I believe that the source cited by Secular Animist gave the electric tractor market size in 2030 of $3,4 billion for the ENTIRE GLOBE, not just the USA. Which would indeed be a paltry share of the $114,5 Bil market projected for 2029.
SA’s source may be optimistic for electric tractors — another source projects a market of only $0.9 billion even by 2032.
https://www.gminsights.com/industry-analysis/electric-tractor-market
2) An even greater negative force is capitalism’s strong insistance on continual growth — which in turn demands continual population growth. See Elon Musk, etc. Or , in addition to the reference I gave above, see the recent article in The Atlantic mag of Laurence Jobs (Apple):
https://www.msn.com/en-us/news/us/the-urban-family-exodus-is-a-warning-for-progressives/ar-AA1ofLOv
Kinda hard to maintain Social Security, Medicare , enormous interest payments on $35 Trillion in federal debt while also spending $Trillions in a Cold War 2.0 nuclear arms race unless you have high growth in population. The billionaires who actually run the USA know that.
The American lifestyle is not known for its small carbon footprint.
Kevin McKinney says
#1 You’d have a point in regard to #1 if it didn’t rely on the tacit assumption that only the US is developing electric tractors. But that assumption, luckily, is counterfactual.
#2–Yes, the growth model is deeply problematic. However, while that’s a worthy (and complex) topic for discussion, it’s not really responsive to most of the previous couple of posts. But if you’d like to discuss it, I’d be more than glad to open a new ‘chapter.’
Don Williams says
1) Please clarify your “counterfactual” – since it seems to be contrary to the facts and to the academic discipline called “arithmetic”.
2) If you track back to the original primary source for SA’s cite, it says that the GLOBAL –NOT just the US – market for electric tractors is only $0.7 bil and is projected to grow to ONLY $3.4 billion by 2030.
https://www.marketsandmarkets.com/Market-Reports/electric-tractor-market-109801941.html
Note that the bulk of the 2030 market is projected to be in Europe –not Asia — since electric tractors are currently uncompetitive on price and it takes a rich country to subsidize them. Also, the Green Party does not fare well among hungry people.
A second industry source that I cited projects much lower growth in sales of electric tractors – less than $0.9 billion by 2032.
3) As I noted above, the GLOBAL market for all tractors including fossil fueled ones is almost 100 times larger – $84.5 billion today and projected to reach $114.5 billion by 2029.
4) You also overlook that the market is sales of New tractors. The larger established plant consists of tractors with diesel engines and those tractors can last a decade or more while continuing to emit carbon.
5) Tractors is just one factor in the carbon emitted while feeding 8 billion people. Another factor I noted above is the carbon emitted from production of the massive amounts of synthetic fertilizer needed every year.
The third factor is that the assumption of declining population is contrary both to the growth we see today and the strong financial motivation our wealthy rulers have to push for continued population growth in the major carbon emitting nations.
Kevin McKinney says
Don, thank you. I appear to have misread the statistic; it does indeed say “global” market, not US market. My bad! However, while we’re doing arithmetic, let’s go a bit farther with it. The report gives a CAGR of 28% pa. for electric tractors. It’s quite likely that that is going to accelerate, but for an indicative result, let’s just examine what happens if 28% is maintained.
–In 10 years, the electric tractor market will hit 11x, or about $8.3 billion. That’s about 10% of the 2024 total tractor market. Is that “paltry” still? I suppose reasonable people might differ on that.
–However, in 20 years, it reaches $96.9 billion, which is more than 100% of the 2024 total market. Definitely not “paltry!” For context, let’s assume what is almost surely another contrafactual, which is that the overall market maintains its current ~5% growth over the same time frame. At that rate, the $84 billion 2024 becomes a $222 billion market, and the electrics would have 43.6% of the market, which I don’t think anyone would call “paltry.”
–25 years on, it’s $334.5 for the electrics, and just $284.5 for the overall market. Game over for ICE tractors, then, some time 20-25 years from now. Which would give zero emissions from tractors, at least, roughly in time for 2050.
You also said:
No, as I read the report, the bulk of the 2030 market is projected to be in Europe because the bulk of the present market is in Europe. The fastest-growing market appears to be in Asia–at least by eyeballing the graph.
I think you misunderstand the current reality, which is that adoption of EV tech is increasingly being driven by economic, not policy factors (though of course, the two interact.) EVs are now cheaper on a lifetime ownership basis in the US, with cheaper upfront costs coming soon. Tractors may be a bit slower, but I have to believe that the growth we’re seeing in the US doesn’t reflect altogether “uncompetitive” economics.
Finally, I’d note that the epicenter of EV innovation today is clearly in China.
Killian says
I smell several Straw Man. Did anyone claim 10 million can be fed by conventional chem ag? Did anyone claim it was good idea and a goal to have? Did anyone claim because of that population just isn’t an issue?
Not that I am aware of, but I don’t read all the comments here and only post occasionally.
I don’t know if these STrw Men are directed at me, but just in case, here’s what I know to be true:
1. Even with conventional, we currently feed 8 billion with 30% being wasted. Clearly, if we did not waste 30%, we could feed that many more people, @ 11.4 billion. However. that would be REALLY EFFING STUPID to do given uch ag practices are destroying our ecosystem.
2. So, when *I* say we can feed 11 or 12 billion I am saying, ALWAYS, so tuck this away in your Straw Man’s little head, we can do that with REGENERATIVE agriculture. See the link last month about a new study stating the benefits of regenerative ag, including yield equal to or better than conventional. This is all the more true when we include that regenerative food has a significantly higher nutritional value. So, no, feeding the world and a few billion more is not a real challenge if we remove the politics and economics that keep people hungry. Physically, easily done.
4. HOWEVER, even in a regenerative system it would be REALLY STUPID to want 10 – 12 billion people on the planet because food is not the only need. Those billions of people consume thousands of other things that also damage the environment. That consumption is very far into overshooting the planet’s systems. We must reduce population significantly if we hope to restabilize the ecosystem long-term AND have a lifestyle that allows some of the creature comforts we have now in the wealthier nations.
5. That said, population demographics move too slowly to have a meaningful impact on climate change and ecosystem destruction, et al. Therefore, population reduction as a primary response to mitigating Climate Change is a poor prioritization of resources and policy-making. (I said this previously, so if your Straw Men were referring in any way to my comments, you must have missed this point.)
6. This does not mean population does not matter. As I said above, we need to reduce population, but it does mean it’s one of the longer-term strategies. However, the demographics are already going that way *without* any explicit policies to move it in that direction in many countries. It is, therefore a moot issue until or unless demographics reverse. Further, the simplest, most effective way to reduce population is to educate girls and women and to give them control of reproduction. So… we really do not need any policies on reduction, per se; equality for women does the job.
7. In the short term, reducing per capita consumption is the low-hanging fruit of solutions. That would be incredibly simple to do. Just stop consuming anything we don’t *need* to consume. Note I did not say *easy.* You have to change the very system across the board to really make it work. But, in the short term, a global response, i.e. most countries agreeing to within their own nations, akin to the sorts of programs the U.S. implemented during WWII would get us…. maybe… 40% of the way there? That might buy us time to go truly regenerative.
Regardless, if we don’t reduce consumption @ 80 long-term, I don’t think society remains anything like stable by 2050. A recent paper found 2050 is the midpoint date for the AMOC shutting down, e.g.
Since all those Straw Men are dead, maybe you can enjoy a pot of Straw Man soup!
Cheers
Don Williams says
Some more facts: UN projects world population to hit 10 billion around 2060 — and I think they are optimistic although they acknowledge uncertainty and that it could possibly hit 11.5 billion by 2100 instead of leveling out around 10 billion.
Africa’s population continues to have a very high growth rate.
https://population.un.org/wpp/Graphs/Probabilistic/POP/TOT/900
Here in the USA some “activists” both on the right (JD Vance, Elon Musk ) and now on the left are advocating for a higher birth rate:
https://www.nytimes.com/2024/08/05/opinion/birthrate-jd-vance-progressives.html
zebra says
Don Williams,
I don’t think you actually read the article or considered who the author is.
False-flag/concern-trolling is increasingly popular these days from the usual suspects.
Don Williams says
The NY Times article was just one article expressing concern over America’s low birth rate.
I don’t think you actually read the Aug 8 post above where I also cited an article in The Atlantic on the subject of a low birth rate. Are you arguing that both the NY Times and The Atlantic are “the usual suspects”?
Without continual growth how will the stock market keep rising, the Rich keep receiving interest on $35 Trillion in federal debt , Social Security/Medicare provided to the elderly and our Cold War 2.0 nuclear arms race funded? By increased taxes on the Rich?
The Rich run America — not philosopher kings who have to beg for research grants every so often. I think population needs to decline but I am merely pointing out the powerful forces of capitalism that will oppose that. Who do you think OWNS The Atlantic?
zebra says
Don Williams
Don, I was responding to your “and now on the left” phrase… I had read the article you described that way previously, and it was obvious to me that it fit into the category I described of false-flag/concern trolling. It was not a “progressive” expressing concern about declining population; it was just promoting the usual Republican talking points about population.
Read it again more carefully and you will see what I mean.
Ray Ladbury says
It is an understatement to say that the situation with respect to population–be it national, global or local–is complex.
Certainly, Earth is now supporting far more humans than it can sustain long term. That excess population is being maintained by massive use of fossil-fuel based fertilizers and pumping water from finite and fragile aquifers. That cannot continue indefinitely and is already irreparably damaging the planet’s long-term carrying capacity–that is, the planet will support far fewer people than it would now.
That said, there is an instability with respect to human demographics–without population growth in a society, you will have fewer productive individuals to support the young and the elderly. This is a situation that only gets worse as people live longer, even if that increased longevity is also accompanied by increased years of productivity, as it is never a one-for-one relation. This is a situation that could be remedied with increased used of improved robotics–although that comes with increased energy consumption and potential instability in labor and employment.
And that brings us to the political and economic. None of the economic systems we have today are stable in an era of decreasing human population. We’ve seen what happens to the Chinese system when population growth slows. Imagine how it would respond to an actual decrease. Capitalism is probably especially vulnerable to instability if population is not growing, as a growing economy will tend to ossify the income/wealth inequality to which the system is susceptible. Long term, that is bound to cause political instability, as people lose hope that their national dream is anything but a fiction for the majority. To some extent, a lower-than replacement birth rate in a country can be tolerated if the country has a liberal immigration policy. Immigrants bring an influx of ready labor as well as cultural variety that leads to a more interesting culture.
Of course, we’ve seen in the US and Europe how white nationalists respond to increased immigration. It is the reason why the likes of Elon and J. D. Vance advocate for larger families and dismiss the ecological threat of rising global population.
And of course there is the historical fact that the few times when global population has actually shrunk have not been fun. It has taken war, plague and famine to do the job, and even then it was not stable and proved only a temporary glitch.
So, we have a situation where we see how things have to change, but there is no idea for how to get there.
zebra says
Ray Ladbury,
Ray, the population discussion requires some better focus and clarity about parameters.
First, are we talking about a single Nation-State or the global population?
I’ve pointed out that if the global population declines, the paradigm changes. I’m not sure what people don’t understand abut the resultant economic system… labor becomes more valuable, and resources become less valuable. How does this mean a better life is “a fiction” for the majority of the population? I would think rather the opposite.
Sorting out the consequences for individual countries when global numbers are increasing or held constant is obviously more complicated. Japan is very different from Russia and USA is different from both. The problem is that people try to produce generalized principles from those cases, which just doesn’t work.
As for “getting there”, we have plenty of evidence of what works… without war and disease and famine. Otherwise, we wouldn’t be having this discussion about low fertility rates, right? The only question is how rapidly we can achieve the result.
Mal Adapted says
Ray:
No need to imagine, FWIW. China’s population has actually decreased in each of the last two years. By my count, the populations of 37 countries have begun shrinking. Many of them are former Soviet Bloc nations. Island nations are also well-represented among the shrinking ones. A number of already-shrinking countries, especially in both Eastern and Western Europe, are undergoing negative economic growth as well.
The next step would be to plot nations of the world with population growth on one axis and economic growth on the other. I couldn’t find a peer-reviewed scatter plot in a few minutes on Google Scholar, but I found some in the “gray literature“. What I found in the peer-reviewed literature was wide agreement that population decline is not strongly correlated with economic decline, as in this Nature article from last year. What will happen to global GDP when global population growth is negative, is far from clear IMO. Interesting times!
Mal Adapted says
Me: population decline is not strongly correlated with economic decline (screw blockquoting + bolding).
Actually, looking at the 62-yr trace of GDP in countries where it’s declining currently, it’s evident to the Mark I eyeball that there’s no correlation between population growth and economic growth in those countries. My own eyeballs glazed over at this point.
zebra says
Mal,
The reference to the Nature article was good but I’m not sure GDP is a meaningful metric for this. Repeating what I said to Ray:
“If the global population is decreased significantly, and held constant, labor becomes more valuable and resources become less valuable.”
That means, in simple terms, you get paid more, and you can own more “land”. What’s the problem?
It’s true that many existing sectors of the economy will become unnecessary. But that’s hardly a problem, since there is plenty of other work to employ the reduced population. The market will decide which activities are worthwhile.
I honestly don’t get it. Is the fear that people will be too happy, and there will not be progress in science or the arts? I doubt it; there are always going to be us curious monkeys in the crowd, who will not be satisfied with the status quo. But, you can’t measure that stuff with this meaningless abstraction of “GDP”.
Susan Anderson says
JD Vance and Elon Musk are nutters about treating women as birth machines. Elon thinks his ‘seed’ is special, and is beyond weird on the subject. There are others, but they only want white and/or Republican babies, and they’re not interested in helping those babies survive (or their mothers, after all, pregnancy is a serious health condition, which men would know if they got pregnant). Since the NYTimes is a public news outlet, it publishes opinion from all points of the compass, and this birth panic is right wing. Your link is particularly dumb, since it ignores/dismisses climate change and other toxic problems from overconsumption and ‘advises’ people from a position of ignorance. Your title mentions progressives but they are not represented in the article except as targets for unwanted advice.
Piotr says
Killian: “we currently feed 8 billion with 30% being wasted. Clearly, if we did not waste 30%, we could feed that many more people, @ 11.4 billion”
If it were so easy to do – why we haven’t done it before? Do the food producers and sellers LIKE seeing MOST of their profits wasted? (if their profit margin was, say, 10%, then if they could sell 30% more, without any increase in constant costs, then new profit margin is 4 TIMES higher). Or do the consumers LIKE paying 30% more for food than they need to?
Killian: “ population demographics move too slowly to have a meaningful impact on climate change”
Spoken like somebody who does not understand the consequences of exponential growth and big numbers. Human population between 1960 and 1987 increased from 3 to 5 bln (66%). With more people and more affluence per capita – the emissions of CO2 increased from 9.4 to 21.3 Gt. (225%). In comparison – how much time implementing of your regenerative agriculture, on the scale large enough to reduce GHG emissions from 225% to 100%, would take? Substantially less than 27 years?
Sure, the current % growth is much less than it used to be, but because there are so many of us – we are already about 50% above Earth carrying capacity – the longer we stay above it, the bigger the PERMANENT damage to non-renewable and previously-renewable resources – and the lower FUTURE carrying capacity of Earth for humans.
So I don’t subscribe to your dismissal of the reductions of human population as “too slow to have a meaningful impact“, particularly that distributing free contraceptives and promoting family planning can be done much quicker then completely reengineering WORLDWIDE agriculture, economy and societal values (replacing consumerism, competition and conflict with simplicity, consideration for others, and harmony.
K.: “ Regardless, if we don’t reduce consumption @ 80 long-term, I don’t think society remains anything like stable by 2050. A recent paper found 2050 is the midpoint date for the AMOC shutting down”
Do I detect a note of … glee (I have been warning you for years, but you never listen)?
K: Since all those Straw Men are dead, maybe you can enjoy a pot of Straw Man soup!
“Let them eat …straw”, Mme Pompadour?
Kevin McKinney says
Yes, it’s easy to assume that food waste is pure negligence and that with just a little more attention it can be eliminated. Our household experience is rather that considerable discipline is required, and even during periods when you are mustering that discipline more or less successfully, you don’t get waste down to zero. The thing is, most food is perishable unless it’s processed in some form or fashion. Are you sick, and unable to keep anything down? That bread is going to mold anyway, and that nicely-ripe apple isn’t going to stop ripening while you heal, either.
In short, stuff happens–at the household level, the retail level, the distribution level, and right back up the chain.
Chuck Hughes says
People need to start factoring in crop failure to their rosey projections about population growth. We’re not going to see 10 billion people without mass starvation. We’re consuming our way to oblivion. People are already moving away from coastal areas due to storms, fires and flooding.
I just don’t see us being able to sustain that many people for very long.
Mal Adapted says
You’re right about the risks of crop failures, but with luck we won’t see mass casualties worldwide before we cap the warming. By we, I mean all humanity. OTOH, the risks increase with both population size and annual fossil carbon emissions. It’s trivially true that whether we can “sustain that many people for very long” is critically sensitive to “how many, for how long?” We can sustain 8 billion now. Will we decarbonize our economy in time to avert a sharp increase in the global death rate? Can we sustain as many as 12 billion (high projections) until that number begins to decline? Projections of either have the same problem of compounding uncertainty due to diverging scenarios.
Geoff Miell says
Chuck Hughes: – “People need to start factoring in crop failure to their rosey projections about population growth.”
Intensifying extreme weather events and an insurance crisis are likely to cause significant economic and political disruption in the U.S. sometime in the next 15 years.
https://yaleclimateconnections.org/2024/08/when-will-climate-change-turn-life-in-the-u-s-upside-down/
Also see/hear the YouTube video titled Human Impact, Extinctions, and the Biodiversity Crisis with Corey Bradshaw | TGS 136, published 14 Aug 2024, recorded 25 Jul 2024, duration circa 2 hours. The show notes include:
https://www.youtube.com/watch?v=qJwsJhFK98o
This comment stood out for me (per the transcript):
[00:38:37] Nate Hagens: Let’s talk about insects. I had a a butterfly specialist, Nick Haddad from Michigan State on, and he gave some just horrifying statistics on insects.
[00:38:49] So lay it on us Corey, what is the situation? My understanding is that we’re losing insect biomass one to two percent a year. And does that at some point play into your co extinction thesis? Have you looked at that?
[00:39:05] Corey Bradshaw: Well, yes. And no. The yes part is that from, from an ecological perspective, once the insects go, you’re looking at a bottom up effect.
[00:39:18] So when we’re talking bottom from the trophic perspective, who feeds on whom, that you could precipitate a lot more extinctions quickly. Actually it’s even below that. The plants are probably even more important because many of the, most insects are herbivorous, right? So they’re eating the plants and then things eat those insects and so on and so forth.
If bees become extinct then many crops likely won’t get pollinated. Crop yields would then plummet.
https://beeaware.org.au/pollination/pollinator-reliant-crops/
Mal Adapted says
Tom Fuller, in last month’s UV thread:
“That 50% seems a bit high. Only 32% of American voters are registered Republican. Not all Republicans are MAGA-heads.
Still far too many, of course.”
Well, Tom, at least we know you’re not a MAGA-head, although I presume we’ve all figured that out by now, despite your penchant for picking fights. But seriously: it looks to me like Nigel’s “50%” was his way of saying “about half”. He’s right, as today’s poll results all show Harris has wiped out the lead Trump held as late as last week (LMGTFY: https://www.google.com/search?q=harris+trump+poll&tbs=qdr:w). Bloomberg.com (paywalled) calls it a “dead heat”. I, for one, am taking heart from the news!
And while not all registered Republican voters may be MAGA-heads, any of them who don’t vote for Harris will effectively be voting for Trump nevertheless. That’s a problem only because there are far too many people, indeed about half of the voters, who will vote for him affirmatively, whether or not they’re registered Republicans or call themselves MAGA-heads!
You know how our system works, Tom. Most of our elections are decided on slim margins, easily reversed in the next cycle. What still puzzles me, is how Americans let ourselves be divided so neatly down the middle. It seems comparable to the blue and green factions at the Byzantine chariot races – a marketing strategy that resulted in deadly confrontations (https://www.smithsonianmag.com/history/blue-versus-green-rocking-the-byzantine-empire-113325928)!
Radge Havers says
“…neatly down the middle…”
Well, wandering off topic, I’d say it could be that political strategists and analysts are all operating at the bleeding edge of their field, sort of like the Olympics where winning can come down to hundredths of a second.
But, to continue the olympic analogy, perhaps Republicans are like the Russians, in that they’re not competitive unless they cheat.
Mal Adapted says
Radge:
it could be that political strategists and analysts are all operating at the bleeding edge of their field.
My thoughts are along those lines also. In the case of electing a POTUS, the two serious candidates must adjust their messages with trepidation, helped by teams of experts, to pick up the largest number of voters on one end of their ideological range while losing the fewest on the other end. Lately, however, it seems to come down to “whatever she’s for, I’m against”, with the voters sorting themselves out into roughly equal numbers.
Radge Havers says
Mal,
“…whatever she’s for, I’m against…”
I agree. I think that’s been brewing for a long time, but IMO things started to break under the strain thanks to the Dubya administration. I doubt there’d be a Trump presidency but for the door opened by Dubya… and probably no Trump as we know him without Roy Cohn– pretty much a straight line from the McCarthy era to Trump… IMO.
Add to that the Internet. Who was it who said, “I never knew how many stupid people there were in the world until I got on the Internet?”
Kevin McKinney says
Equal numbers? Maybe. I have a sneaking suspicion that they won’t be looking so equal come election day. But we’ll see… and we definitely don’t want to take it for granted.
Thomas W Fuller says
At this point I’m not thinking about elections, I’m thinking about the make-up of the American adult population. Don’t worry, I’ll be obsessing about the election soon enough. And yes, I do know how ‘our’ system works.
I left America because the atmosphere had grown too toxic for me. However, I don’t for one minute think that half of Americans are infected with the MAGA disease. Maybe a quarter.
Sadly, a quarter is enough to ruin a country.
Kevin McKinney says
It may be a skitch better than that; a good chunk of Trump’s support comes from ‘low-propensity voters.’ And his plan for getting them out seems a bit reminiscent of, say, his efforts to fight Covid:
https://washingtonmonthly.com/2024/07/30/what-trump-meant-by-you-wont-have-to-vote-anymore-is-weirder-than-you-think/
But it’s still crazy, and deeply unsettling, how much support he and the GOP have, even though literally every ‘theme’ of their coronation–er, convention–was based on a false premise. Denialism isn’t just for evolution, smoking, and climate change any more.
So if you American, please get out and Vote Climate in November!
Jonathan David says
Interesting question. This may be a function of election dynamics and resource and funding allocations by political strategists. In elections where a party has an easy win, there are incentives to minimize efforts in those elections. For example, in the industrial states: Wisconsin, Michigan, Pennsylvania, etc. the Democratic party has long held a clear advantage due to the support of unions, arguably leading them to take these votes for granted. The current Democratic strategy has been to shift efforts instead to Georgia, Arizona and even Texas. The minority party, if seeing an opportunity, will expand efforts in those states which have been neglected by the opposing party. If they choose to do so, it’s not necessary to expend more effort than a sufficient level to achieve a win, additional efforts result in loss of efficiency of resource allocation. Over time this could lead to the near-equilibrium electoral balance we see today.
Mal Adapted says
Good insight, The selection of Tim Walz as Harris’s running mate seems mindful of the Upper Midwest, to assure those voters they aren’t overlooked. Exciting times!
Michael Long says
Politico 101: About 40% of the people in the US will vote Democrat, not matter what. About 40% of the people in the US will vote Republican, not matter what. Doesn’t matter why, they just do.
Which leaves just 20% as independent and. on the fence. And it’s that 20% who decide elections. When you consider that about two-thirds (66%) of the voting-eligible population turned out for the 2020 presidential election, that leaves just about 34 million people to decide the fate of the nation.
And given the electoral college, many of those people are in areas where it doesn’t matter how they vote, as the state swings the way the state swings.
Which puts any national election is the hands of a very, very small group of people.
Scary when you stop to think about it.
Barton Paul Levenson says
Does Russell Seitz still post here?
Kevin McKinney says
Yes, I’ve seen him relatively recently, at least.
Barton Paul Levenson says
Thanks.
Russell Seitz says
Sent you my gmail email per your request
Piotr says
JCM “ [patrick’s] 0.3K guess could represent (0.3K/1.5K) 20% of human-caused global warming to date. A significant figure”
No. the human changes in the water cycle are not significant compared to the human emissions of GHGs. I have already explained to you before, but since you behave as if this wasn’t said, here is a summary:
1. I have shown that patrick “+0.3K” is major OVERestimation: he calculated it for the maximum theoretical effect: that during the fallow season the evaporation from croplands is ZERO (i.e. “desertland”). Since the real croplands during the fallow season is not as dry as a “desert” – the resulting drop in evaporation is only a fraction of the calculated one, and therefore 0.3K becomes a “ fraction of 0.3K”
2. Furthermore, patricks 0.3K did not account for the human irrigation of the crops. The resulting increased evaporation COUNTERS the reduction of evaporation from croplands during the fallow season, i.e. causes a COOLING – that counters all or part of your fraction of 0.3K warming from p.1.
Your best counter to the 2 points above was to … dismiss the value of the climate modelling as: “ imaginary process mechanisms” with “rules about how things ought to be ” according to their authors. Since I have not done either – it must apply to Lague et al. whose modelling paper your brought up, and to climate models in general.
As for your claim of the significance of the human changes in water cycle to the rate of AGW – your warming by a fraction of a fraction of 0.3K happened over …. MANY THOUSANDS OF YEARS, while the current warming by the GHGs levels happens at the rate of about 0.2C/DECADE. So the RATE of global warming caused by reduction of evaporation from croplands is ca. 3 orders of magnitudes LOWER that the rate of warming from human-emitted GHGs.
Unlike you, I don’t consider something that is 3 ORDERS of MAGNITUDE smaller – “ A significant figure”.
JCM: “ Adding in a 5% loss of soil organics and the missing atmospheric carbon sink increases the ecological destruction to roughly 25% of global warming by including major trace gas effects ”
Don’t you even read your own posts??? Your entire claim to fame is that it is “ mindboggling” that the climate scientists in the world continue ignore, what you, a layman in his free time, has been able to figure out – that the RELATIVE importance of the human changes in the water cycle are “significant” COMPARED TO the effects of human changes in GHGs, say:
“ hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
And now you use the same “outputs of trace gases” to … beef up the importance of the water cycles change over …. the human-caused increase in “trace gasses” ????
You see the logical problem in that, right?
Tomáš Kalisz says
In Re to Piotr, 1 AUG 2024 AT 2:11 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823538
Dear Piotr,
Your argument that the rate of global surface temperature changes does not fit the rate in (assumed) anthropogenic changes in terrestrial water cycle is reasonable.
I would be, however, still cautious in drawing a bold conclusion in the sense that human interferences with terrestrial water cycle have a negligible influence on global climate.
1) It appears that Lague 2023 is, if not the very first, at least a quite rare work directly aimed to exploration of this relationship.
2) Climate is not the same as temperature. We can and should ask if
changes in water availability for evaporation can or cannot change terrestrial precipitation patterns.
3) Personally, I have a suspicion that although the direct influence of anthropogenic interferences with terrestrial water cycle on global surface temperature may be small, it may be still well possible that their influence on climate sensitivity towards other anthropogenic “forcings”, such as greenhouse gas emissions and/or atmospheric pollution with aerosols, may be significant.
4) It is my understanding that a similar simulation method as used by Lague 2023 could serve for an estimation if there is any difference in climate sensitivity (e.g. towards a change in atmospheric CO2 concentration) between the “swamp land” and the “desert land”. If you think so, I would like to ask if you would be willing to support a plea to moderators for a comment if a such study could be worth of an effort?
Greetings
Tomáš
David says
Links to a new research article and its supplementary materials on: “anthropogenic amplification of precipitation variability over the last century”
https://www.science.org/doi/10.1126/science.adp0212
.
https://www.science.org/action/downloadSupplement?doi=10.1126%2Fscience.adp0212&file=science.adp0212_sm.pdf&
.
I know Tomáš Kalisz’s writings are focused on something different, but thought this still was worthy of posting on this thread.
Piotr says
David: I know Tomáš Kalisz’s writings are focused on something different
precisely – these are changes in precipitation as an INDIRECT result of humans warming world with increased GHGs.
But it won’t likely stop Mr. Kalisz from profusely thanking you for the interesting paper and then ignoring your caveat and using this paper as a further support for his and JCM appeals to refocus research interests and the finite financial resources from the mitigating AGW via the most -cost-effective way (reduction of GHGs) to the one least ineffective and already at the unsustainable level, as we are rapidly depleting the ground water.
JCM says
Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Curiously, simulations under CMIP6 expect an increase in ET driven by an increase in temperature from radiative forcing. Given the existing moisture limitation, an increase in ET must also be associated with an increase in moisture availability on land. Models must therefore project an increase in moisture availability with warming to maintain the stability factor.
Observationally, by various measures, analyses have suggested that much of the earth has been drying in recent decades e.g. “An overall consistent increase of global aridity in 1970–2018” https://link.springer.com/article/10.1007/s11442-023-2091-0
“””This study investigated spatiotemporal variability within global aridity index (AI) values from 1970–2018. The results revealed an overall drying trend (0.0016 yr−1, p<0.01), with humid and semi-humid regions experiencing more significant drying than other regions, including those classified as arid or semi-arid."""
This seems to defy a globally averaged increase in moisture availability, and must therefore limit an increase in ET. Considering an important factor in moisture availability is precipitation, this introduces some circularity as continental moisture recycling contributes a large proportion.
Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change. While it is likely that heavy precipitation events are increasing, these may be balanced by longer periods of dry in annual mean.
In terms of moisture availability, precipitation intensities which exceed catchment infiltration rates will result in a net drying. Catchments operate most effectively with low intensity frequent rainfall along with nice spongy storage properties such as healthy soils, wetlands, and other biosystems. Catchment properties, along with moisture recycling, may impact both moisture availability and the associated precipitation regime.
Damaging catchments reduces their infiltration and moisture storage, and precipitation intensities will more often exceed infiltration. Reduced moisture availability in space and duration reduces moisture recycling and decreases the precipitation frequency. This feeds-back into warmer temperatures, more precipitable water, and a higher intensity of rainfall upon oceanic moisture import on large scale frontal systems. Counterintuitively, flood and drought are flipsides of the same coin, as too much water all at once is ineffective for recharge.
Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Some insights are offered in: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022EF002859
Unfortunately, only three CMIP6 ESMs out of about 30 include irrigation, and all three assume unlimited water availability for this purpose. Overall a small proportion of foodcrop parcels receive irrigation at some time, focused almost entirely in southern asia. For any given ESM grid cell, the vast majority are 0-5% irrigated. In previous discussions I recommended up to 20% irrigation offset factor during the growing season when converting nature to foodcrop parcel as an upper bound. The effect of moisture availability or absence appears to be practically immediate in ESM. The most abundant foodcrops are generally left to dry (or actively dried) on the field upon maturation – this commences around now in early August in northern-mid latitude.
Given that only 3 ESMs include irrigation, but the CMIP6 overall tends to overestimate an increase in ET over time, this suggests some seriously overlooked factor. Needless to say, including irrigation additionally in all CMIP6 members will result in dramatic overestimates of ET in the ensemble mean. Some compensating factor will need to be recognized, and the most obvious one to me is the profound catchment deterioration and ecological destruction. This annually averaged net desiccation, along with the associated increasing temperature and hydrological extremes, imposes an obvious climate change influence IMO. For globally averaged climate enthusiasts, this may indicate also a diminished climate stability over time simultaneously with radiative forcing.
I will be on holiday in Colorado in the coming days so expect delayed response. cheers
Piotr says
JCM AUg.6: “Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Except, that we live on a planet that contains oceans, covering 71% of Earth surface, as well lakes, swamps, and rivers, and we live on a planet that has winds – so the water vapour is carried from places where evaporation is unlimited to places where it is limited,
To the extent that Lague et al. state that “the atmosphere has MORE total water vapor in DesertLand than SwampLand simulation. (This seemingly paradoxical result is a consequence of Clausius-Clapeyron law). Which means that the outcome of human irrigation is far from certain – if it helps to increase absolute humidity but without crossing 100% – it would be all warming (absorption of LW by water vapour) and no cooling (by cloud albedo).
More importantly Lague et al put constraints on the effect of evaporation – the MAXIMUM difference in global T (Desertland-Swampland) – around 8K. However, most of the world FAR from being Desertland, and on top of that – irrigation won’t likely convert the deserts all the way into swamps. Consequently, the room for ACTUAL cooling EVEN IF we had UNLIMITED capacity of irrigation – is only a SMALL fraction of that 8K.
But our capacity for further irrigation are the opposite of “unlimited”,
– not only it would require building a mind-boggling amount of new infrastructure to cover the land that could use more water over at least a part of the year,
– but there is not enough water to supply it there.
In fact, the hot dry places that could use extra water MOST, typically don’t have any more water to use left – either because this water is absent (world deserts), or already used it. In fact, in many parts of the world – the future irrigation is likely to decline since we are emptying aquifers often irreversibly (when then pore space in the acquifers, once drained, collapses).
Not mentioning that the more irrigation in warm dry climates – the bigger the soil salinization that harms the very plants we try to help.
Desalination of seawater – is not a solution either – it just can’t produce nowhere near enough of fresh water to cool the global temp. in any meaningful way, and being very energy intensive – its GHG emissions may warm the climate more than the cooling by the extra irrigation.
Hence we don’t have enough water to irrigate to make any dent in the AGW worth of talking.
JCM: Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Not really. I have said that the effect of crop irrigation would further reduce the already small
climatic effect (a fraction of 0.3K warming) caused by reduction of evaporation due to conversion of natural ecosystems to croplands, thus reinforcing my point that reduction of AGW via direct intervention (irrigation) – is probably the least effective^* way of all the ways to mitigate global AGW, and the most limited one – given huge amount of water needed to have any measurable effect and not enough freshwater resources that we have not already tapped.
____
^* “The least effective” is based on the elementary scale analysis: human alterations to evaporation are MINISCULE comparing to the natural fluxes, and the residence time of water vapour is measured in days, not decades like in human perturbation of GHGs.
JCM says
Given that continents are generally moisture limited, moisture availability imposes a strict constraint on the evapotranspiration, and therefore climate stability.
Curiously, simulations under CMIP6 expect an increase in ET driven by an increase in temperature from radiative forcing. Given the existing moisture limitation, an increase in ET must also be associated with an increase in moisture availability on land. Models must therefore project an increase in moisture availability with warming to maintain the stability factor.
Observationally, by various measures, analyses have suggested that much of the earth has been drying in recent decades e.g. “An overall consistent increase of global aridity in 1970–2018” https://doi.org/10.1007/s11442-023-2091-0
“””This study investigated spatiotemporal variability within global aridity index (AI) values from 1970–2018. The results revealed an overall drying trend (0.0016 yr−1, p<0.01), with humid and semi-humid regions experiencing more significant drying than other regions, including those classified as arid or semi-arid."""
This seems to defy a globally averaged increase in moisture availability, and must therefore limit an increase in ET. Considering an important factor in moisture availability is precipitation, this introduces some circularity as continental moisture recycling contributes a large proportion.
Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change. While it is likely that heavy precipitation events are increasing, these may be balanced by longer periods of dry in annual mean.
In terms of moisture availability, precipitation intensities which exceed catchment infiltration rates will result in a net drying. Catchments operate most effectively with low intensity frequent rainfall along with nice spongy storage properties such as healthy soils, wetlands, and other biosystems. Catchment properties, along with moisture recycling, may impact both moisture availability and the associated precipitation regime.
Damaging catchments reduces their infiltration and moisture storage, and precipitation intensities will more often exceed infiltration. Reduced moisture availability in space and duration reduces moisture recycling and decreases the precipitation frequency. This feeds-back into warmer temperatures, more precipitable water, and a higher intensity of rainfall upon oceanic moisture import on large scale frontal systems. Counterintuitively, flood and drought are flipsides of the same coin, as too much water all at once is ineffective for recharge.
Piotr has recommended an offsetting irrigation factor for ecological destruction which may stabilize climate observables.
Some insights are offered in: https://doi.org/10.1029/2022EF002859
Unfortunately, only three CMIP6 ESMs out of about 30 include irrigation, and all three assume unlimited water availability for this purpose. Overall a small proportion of foodcrop parcels receive irrigation at some time, focused almost entirely in southern asia. For any given ESM grid cell, the vast majority are 0-5% irrigated. In previous discussions I recommended up to 20% irrigation offset factor during the growing season when converting nature to foodcrop parcel as an upper bound. The effect of moisture availability or absence appears to be practically immediate in ESM. The most abundant foodcrops are generally left to dry (or actively dried) on the field upon maturation – this commences around now in early August in northern-mid latitude.
Given that only 3 ESMs include irrigation, but the CMIP6 overall tends to overestimate an increase in ET over time, this suggests some seriously overlooked factor. Needless to say, including irrigation additionally in all CMIP6 members will result in dramatic overestimates of ET in the ensemble mean. Some compensating factor will need to be recognized, and the most obvious one to me is the profound catchment deterioration and ecological destruction. This annually averaged net desiccation, along with the associated increasing temperature and hydrological extremes, imposes a climate change influence IMO. For globally averaged climate enthusiasts, this may indicate also a diminished climate stability over time simultaneously with radiative forcing.
I will be on holiday in Colorado in the coming days so expect delayed response. cheers
Tomáš Kalisz says
in Re to JCM, 6 Aug 2024 at 10:46 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823592
and Piotr, 7 Aug 2024 at 7:43 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823601
and 7 Aug 2024 at 10:02 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823602
Dear Sirs,
JCM’s paragraph starting with
“Rigorously, climate classifications are to include the mean and variability of weather variables. A stable mean along with increased variability is one indicator of a climate change.”
acted as an incentive for me to repeat my question that I asked
(on 4 Aug 2024 at 7:57 AM, https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823562 )
to Piotr:
“It is my understanding that a similar simulation method as used by Lague 2023 could serve for an estimation if there is any difference in climate sensitivity (e.g. towards a change in atmospheric CO2 concentration) between the “swamp land” and the “desert land”. If you think so, I would like to ask if you would be willing to support a plea to moderators for a comment if a such study could be worth of an effort?”
Please note that in the graph of annual precipitation from land-based stations
https://ourworldindata.org/grapher/global-precipitation-anomaly ,
it appears that the variability in annual terrestrial precipitation since ca 1950 may be higher than in previous ca 50 years.
I am not qualified for a statistical evaluation if there is indeed a such difference, and would like to ask if someone could confirm or disprove it. Again, similarly as in case of my question regarding the relationship between water availability for evaporation from land and climate sensitivity towards other forcings (like changes in insolation, greenhouse gas atmospheric concentration and/or atmospheric aerosol pollution), I suppose that it is a question that might be best replied by climate science professionals and that it may deserve their attention,
because it appears that there may be still a knowledge gap in this direction.
If so, would you be willing to support a plea to moderators for a comment?
Best regards
Tomáš
David says
Tomáš wrote: “it appears that the variability in annual terrestrial precipitation since ca 1950 may be higher than in previous ca 50 years. I am not qualified for a statistical evaluation if there is indeed a such difference, and would like to ask if someone could confirm or disprove it.”
.
And then wrote: “Again, similarly as in case of my question regarding the relationship between water availability for evaporation from land and climate sensitivity towards other forcings (like changes in insolation, greenhouse gas atmospheric concentration and/or atmospheric aerosol pollution), I suppose that it is a question that might be best replied by climate science professionals and that it may deserve their attention, because it appears that there may be still a knowledge gap in this direction. If so, would you be willing to support a plea to moderators for a comment?”
.
I’m curious how you reasonably expect a simple reply here in the comments could “confirm or disprove” the matter to your satisfaction? Based on your responses to the various efforts of other commentators who are far smarter than I to address your questions over the past months and months, I’d predict any succinct response would be insufficient.
Tomáš, if your question of swamp/desert land evaporation and mankind’s impact on said lands and the resulting impacts to temperature and precipitation amounts/patterns verses the impact of mankind’s introduction of GHG’s into the atmosphere is really that important for you to understand, than have you considered participating directly in an effort to analyze your question via your own research project?
Just my “layman” opinion.
Piotr says
T. Kalisz Aug.9 to repeat my question that I asked
I don’t see my answer to that question, so I’ll write it again:
TK: 1) It appears that Lague 2023 is, if not the very first, at least a quite rare work directly aimed to exploration of this relationship.
So what? Do you have a proof that its findings are NOT credible? After all – it was brought up and extensively quoted by JCM, and used by him and you as SUPPORTING your claims about the importance of human alteration of water cycle to AGW. It seems that it …. STOPPED to be credible:
– JCM: “imaginary process mechanisms [following ] rules about how things ought to be [according to their authors”
– you – that it is just one study
ONLY AFTER patrick and I have used the numbers from Lague to show that you both MISREPRESENTED the paper, as supporting your claims.
TK: “ 2) Climate is not the same as temperature.
Tell this to JCM and yourself – since both of you have used the TEMPERATURE results of the Lague’s, as the measure of the importance of the water cycle compared to the GHGs effects on temperature. Therefore, “ Climate is not the same as temperature” is a cop-out after not being able to sustain your argument.
TK: “ 3) Personally, I have a suspicion
Your “beliefs” and “suspicions” are IRRELEVANT until you support them with a defensible argument.
TK: “ 4) “would you be willing to support a plea to moderators for a comment if [a followup study using Lague’s approach] could be worth of an effort?”
No I wouldn’t. Lague’s model have only to put some numbers to illustrate what anybody knowing anything the water cycle already knew from the elementary scale analysis:
Humans do NOT have any appreciable effect on the global T via direct increasing or decreasing evaporation BECAUSE of the MASSIVE VOLUME of the natural water fluxes, and extremely short residence time in the atmosphere (several DAYS). Contrast that with humans GHG emissions which are much bigger % of the natural ones, and the perturbation time of GHGs is measured in at least DECADES, instead of DAYS as in the case of water vapour.
Therefore, you could have a 1,000 studies using Lague’s framework and STILL get the same answer – HUMAN direct modifications of evaporation are just too small to have any significant effect on the Global T. I.e. the conclusions OPPOSITE to your and JCM claims, best summarized by JCM in his recent rant in which he blamed desertification and other ecological calamities on …. considering the AGW being primarily driven by the changes in GHGs, I quote:
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases ”
(c) JCM
The fact that both of you REFUSE to acknowledge the conclusions drawn from not only from your own source but also from a basic scale analysis of relative effects the human perturbation of the water cycle vs that of GHGs – means that:
– either you are unable to accept the quantitative falsifiable arguments that go against your a priori “beliefs” and “suspicions”
– or that you know that it is false, but still follow the old denier’s trope: “Anything but GHGs”, thus diluting the urgency of the global reductions in GHGs, and/or suggesting that the research effort and limited resources should be shifted away from the most cost-effective way to mitigate AGW (via GHG reductions ) to the least effective one (direct changes evaporation).
And in doing so – being “useful idiots” of fossil fuel oligarchy, and tyrannies the depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad:
by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.
So no – I won’t join you in THAT.
Radge Havers says
TK,
The moderators read the comments and periodically respond to ideas that are at least interesting if not important. Perhaps you should take a hint from their silence on the matter.
Tomáš Kalisz says
in Re to David, 9 Aug 2024 at 1:05 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823638
Dear David,
Many thanks for your comments.
As regards my open question if the perceived increase in terrestrial annual precipitation variability from the NOAA data can be significant or insignificant, I think that an ideal reply would have been a reference to a scientific article analyzing this data.
As regards my open question if there still may be a knowledge gap regarding the relationship between water availability for evaporation on one hand and climate sensitivity towards other forcings on the other hand, I would appreciate any comment from climate science professionals. In case that this knowledge gap does indeed exist, the answer “yes” will be sufficient. If my suspicion in this direction is in fact false, I would of course appreciate a more detailed answer, e.g. a few references to articles dealing with this topics. Or, ideally, a popular review article on this topics by one of the hosts of this website.
As regards your question why I do not resolve my question(s) myself by my own research, I must reply that as a chemist, I do not have the necessary training for climate modeling. And, more importantly, I am afraid that doing any research of this kind is in fact beyond my capabilities.
Greetings
Tomáš
Tomáš Kalisz says
in Re to Radge Havers, 10 Aug 2024 at 11:27 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823646
Dear Radge,
You may be correct – and you may not be correct. I do not know.
I would much more than mere silence prefer at least a short comment, like “You are wrong, there is no knowledge gap that you assume. Exemplary publicatioons about the relationship between water availability for evaporation and climate sensitivity towards other forcings are A, B, C, D (citations)”.
Or, aternatively: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings,”
Or: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings,”
Or, aternatively: “You might be right. I am not aware of any publication dealing with the relationship between water availability for evaporation and climate sensitivity towards other forcings, Why do you think that this topics could be of any importance?”
This might prevent lot of noise on this discussion forum, I think. To be honest, lot of contributions published herein raised my doubts if this discussion is really “moderated”.
Greetings
Tomáš
Radge Havers says
TK,
Again, the name of this thread is “Unforced Variations.” It’s a space to help keep distracting comments out of the comment sections for posted articles. Not long ago RealClimate was about to shut down comments altogether, because they didn’t like what they were hearing and relatively few of the visitors to the site read the comments anyway. So it’s become free form.
Now if you haven’t noticed, the moderators do occasionally respond to comments and requests– like Zebra asking that the comment roll be lengthened. Maybe they simply don’t respond to being bated or to ankle biting or are too busy to give a definitive answer to a relatively minor question, but for whatever reason your request is being ignored.
Doing the same thing over and over and expecting different results is insanity — which now that I think of it, is sort of like trying to talk sense to you.
Tomáš Kalisz says
in Re to Piotr, 9 Aug 2024 at 3:40 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823643
Dear Piotr,
Thank you for your reply.
I tried to structure my orevious post into four points for a better readability, however, there was basically a single idea:
There may be many reasons why construing Lague 2023 the way you do it (that human interferences with terrestrial water cycle have no substantial influence on global climate) may be a too bold and potentially misleading generalization.
Please try to be a little bit more generous and read the phrases like my “suspicion” just as questions, e.g.: Can we, based on the present knowledge, exclude this or that?
I think that asking such questions is not a sin or a crime, oppositely – I believe it may reveal existing knowledge gaps. Should a knowledge gap exist, I think that the better way how to deal therewith may consist in directing scientific research thereto.
If Lague 2023 is indeed a single work that tried to clarify the relationship between terrestrial water availability and global temperature, and if this work is still completely silent about the relationship between terrestrial water availability and climate sensitivity, then I think that my suspicion that (read: my question if) there may still exist a significant knowledge gap may be indeed relevant.
I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes, their hybrid wars against democratic states and/or fossil fuel business.
I believe that if you see the situation I tried to describe (that there might be still a knowledge gap, at least with respect to the relationship between terrestrial water availability and climate sensitivity) similarly, no harm would have arose for your efforts and/or for your integrity if you joined my plea for a such comment.
Greetings
Tomáš
Piotr says
Tomas Kalisz: “I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes”
On its own – not; in the context of your and JCM activity on this forum – it is:
Your never accepting answers that don’t fit your deniers narrative (“Anything but GHGs”) , your cherry-picking only those parts of answers that you can misrepresent as supporting your claims, and your incessant sealioning (“ a type of trolling [by] pursuing people with relentless requests for evidence, often tangential or previously addressed, while maintaining a pretense of civility and sincerity (“Thank you for your reply.”). It has been likened to a denial-of-service attack targeted at human beings – are all characteristics of a troll..
And since you. Tomas Kalisz, have been trying for more than a year to seed doubt in climate science, and distract the attention from the urgency of the reduction of GHGs – you are either a paid troll, or “ a useful idiot of fossil fuel oligarchy, and tyrannies that depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad: by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.“..
By their fruits, not their protestations, you shall know them. Particularly that the lady doth protest too much.
Tomáš Kalisz says
in re to Piotr, 11 Aug 2024 at 11:21 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823673
Dear Piotr,
Thank you for your feedback.
Whereas climate science is carried out by climate scientists, its public picture is being shaped by both the climate scientists themselves as well as by various educators and media. Therefore, I think that the climate scinece in its entirety can (but does not nessarily need to) differ from its public picture.
I assume that the prevailing public picture of climate science is shaped by IPCC reports. It is in my opinion quite good in presentation of the present level of knowledge. What I consider as its weakness is presentation of existing knowledge gaps, which is in my opinion quite poor.
In my posts of 20 Jul 2024 at 6:34 PM,
https://www.realclimate.org/index.php/archives/2024/06/unforced-variations-july-2024/#comment-823335
and of 21 Jul 2024 at 7:41 AM,
https://www.realclimate.org/index.php/archives/2024/06/unforced-variations-july-2024/#comment-823346 ,
I mentioned the idea of a Czech philosopher Jak Kršňák that nevědění (which I understand as “awareness of a lack of a specific knowledge”) is equally important as knowledge (vědění) itself.
It is my personal experience that decision making based primarily on available knowledge is very often heavily biased, because existing knowledge is in most cases insufficient. Awareness of existing knowledge gaps and considering risks that a crucial knowledge can be still missing is often helpful and may prevent wrong decisions. For an analogy: Good drivers are aware of dead angles in their view from the car.
The goal of my questions is to find out how much are climate scientists aware of dead angles in their present view on Earth climate. I admit that my questions may sometimes cast doubts about the prevailing public picture of climate science. It appears that the key aspect in which we differ from each other is ithe question if in our view on such doubts.
Personally, I am more confident in persons and institutions who know and are able to admit their knowledge gaps than in those who do/are not. It is my feeling that the revailing public picture presenting the climate scince as “fully settled” is potentially dangerous.
I think that at least on a few details discussed herein, I have already seen the complexity of the studied problem. I can therefore hardly believe that the available projections are fully reliable. If they are not fully reliable, we have to consider also the risk that proposed measures based on these projections may fail. Unfortunately, I miss this approach in present public discourse. Rather, I have often a feeling that we believe that there are no dead angles in our view on Earth climate at all, and that there is no need to ask questions and/or consider alternatives and fallback solutions, because everything is clear.
I would like to find out if the climate scientists themselves really see their existing knowledge so satisfying that they share your view that a question from the public if there still may or may not be an unexplored niche in a specific direction should be dismissed as an effort to undermine and discredit everything what their science reached so far.
Greetings
Tomáš
JCM says
Your contempt is noted, but it is misplaced given our shared professional and personal interests in climate stabilization.
There’s no use in talking past each other, inventing quantities, and reducing ourselves to scoring cheap debate points. I understand clearly that you believe, using your imagination, that a foodcrop parcel has no influence and that you have conjured specific quantitative values. Additionally, the pseudologia fantastica of fabricating and subsequently believing that I am an agent for GHE denial has resulted in significant barriers to communication. This I know for certain. It is obvious your goal is to advocate for trace gas emission cuts by minimizing the complications of landscape aspects to extraordinary extremes. I understand you are passionate in your beliefs, but it seems to me you are performing for an imagined audience rather than engaging with me substantively.
Moving on, as discussed elsewhere, themes in the IPCC-related documents that frame desertification in terms of trace gas GHG emission versus surface albedo are very likely misleading. In my experience and opinion, it’s damaging and incredible that the community would summarize for policymakers that totally destroying vast acreages at the scale of continents has no net consequence on climate observables—allegedly because the surface albedo compensates for the trace GHG effects almost exactly. It should be obvious, and not a stretch of the imagination, that something significant is missing in that idea. There is no use in conceptually minimizing the billions of hectares of landscape disturbance during our lifetimes. No use at all.
From first principles in traditional teaching, landscapes are central to all things in culture and life. It’s really quite simple to understand that the disappearance of the vast majority of functional ecologies will present as Earth System change. Refusal to acknowledge this wisdom is misplaced. Spiritually, these teachings draw parallels between a lack of respect for land and a lack of respect for humanity as well.
The terrestrial destruction curve resembles a hockey stick shape, with the most pronounced deterioration since mid-20th century. The hockey stick aligns with many other Earth system variables. Regarding the 20% + 5% issue, the message is quite simple—profound deterioration of landscapes expressed in moisture, biological and nutrient cycling may have an outsized influence on realclimates (many times) compared to the trace gas effect. Therefore, evaluating landscape-climate interactions in terms of trace gas budgets misses the target, and results in huge undervaluation in policy advice.
Johan Rockström offers a framework through his planetary boundaries setup at Potsdam, promoting an understanding of the interconnected planetary machinery. He lists the big four workhorses as biodiversity, land, freshwater cycling, and nutrient cycling. These intersect intricately with overarching global climate, ocean, and carbon cycles. He promotes improved interdisciplinary engagement and notes how the silos of the various research streams have yet to intersect. However, he seems encouraged that the gaps are closing. He cites specific examples of tipping point elements reached much more easily when planetary boundaries such as biosystems and hydrologies are pushed concurrently with carbon dioxide.
My professional experience is in environmental monitoring, landscape stewardship, conservation, and restoration. This is not a layman’s point of view. Additionally, the modeling community demonstrates that terrestrial ET change in reanalysis does not match at all with what’s in CMIP expectations, and that TOA trends in SW are much more pronounced than expected. This supports the hypothesis that landscape deterioration impacts significantly climate observables. For each new acre of wetland drained, surface sealed, and soil desiccated pushes us deeper into uncharted territory.
It is obvious that the conventional forcing feedback analysis produced by computation in the climate space has much room for improvement. Improvement will be necessary in order for mathematical formulation to close the gap behind the essential wisdom already known since forever.
Piotr says
JCM Aug 5: Your contempt is noted, but it is misplaced given our shared professional and personal interests in climate stabilization.
Contempt implies unfair and unsupported with arguments dismissal of other people. Sounds like an apt self-description on your part. It does not apply to me since I have critiqued your claims and your logic with falsifiable arguments. What those arguments, and your inability to falsify them speak about you, is for the readers to judge. By their fruits, not their declarations about themselves, we shall know them.
And no, I don’t think that we really share the interest in climate stabilization – you follow an old denier’s narrative – “ Anything but GHGs” – for years(?) you have been trying to pump up the “mindboggling” importance of human changes to the water cycle at the expense of minimizing the importance and the urgency of the reduction in GHGs, which you discredit as “an artificial fixation and overemphasis on the outputs of trace gases”, and held responsible for desertification and catastrophic ecosystem destruction:
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases
So since you attack the MOST -effective method of reducing AGW (reduction in GHGs) in favour the LEAST-effective one ^* of direct increase in evaporation – then objectively, you are working against the stabilization of global temperature.
And you are helping Russia and Saudi Arabia, which regimes and ability to project power abroad would collapse without the world’s willingness to continue buying their oil and gas.
By their fruits we shall know them.
—
^* least effective – given how small human impact is compared to the volume of global water cycle, and how short the residence time of water vapour in the atm is (~ week) – compared to massive perturbation of natural levels of GHGs by humans and the perturbance residence time measured not in several days, but decades.
Atomsk's Sanakan says
The RealClimate page for “Climate model projections compared to observations” says:
“If you have suggestions for additional comparisons, stylistic changes, clarifications etc., please leave a comment on the latest open thread.”
https://www.realclimate.org/index.php/climate-model-projections-compared-to-observations/
The link for “open thread” comes to this page. So I’m suggesting a comparison to warming projections in the IPCC’s 1990 First Assessment Report.
Information on the projection from that report:
– projected warming: figure A.9 on page 336, top-right of page xi, bottom-right of page xxii
– projected radiative forcing: figure A.6 on page 335
– projected greenhouse gas increases: figure A.3 on page 333
https://web.archive.org/web/20190314070419/https://www.ipcc.ch/site/assets/uploads/2018/03/ipcc_far_wg_I_full_report.pdf
[image for figure A.9: https://archive.is/QXJ0k/afe22294895246faa7202d65f0e4fdd185aa8635.png ]
Prior assessments of that 1990 report:
– https://doi.org/10.1029/2020EO151822 (figure 1)
– https://doi.org/10.1029/2019GL085378
– https://doi.org/10.1038/nclimate1763
IPCC 2021 Sixth Assessment Report’s assessment of that 1990 projection:
“Under these actual forcings, the change in temperature in FAR [IPCC 1990 First Assessment Report] aligns with observations [page 186].”
https://web.archive.org/web/20230930165550/https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter01.pdf
[image on page 185: https://archive.is/aySSt/9d56525f6ba5a9ef23995280531220ad89daf7d4.png ]
Barton Paul Levenson says
Does Russell Seitz still comment here? I need to get in touch with him.
jgnfld says
Re. https://www.realclimate.org/index.php/archives/2024/06/unforced-variations-july-2024/comment-page-2/#comment-823530…
Some trenchant points. One thing I must disagree on. Cooling was NEVER an equally regarded hypothesis.
https://journals.ametsoc.org/view/journals/bams/89/9/2008bams2370_1.xml
Jim Galasyn says
This Scientist Has a Risky Plan to Cool Earth. There’s Growing Interest.
Edward Burke says
I beg indulgence here for a c. 900-word essay (with apologies here for formatting irregularities):
Now that we’ve managed to enter the second half of 2024 CE, it might have become time to consider our overweening reliance on electricity for living our contemporary lives.
Insofar as the politics of energy and energy supply, generation, and distribution require more and more political dithering globally and within domestic polities worldwide, citizens who might decide they can no longer rely entirely on political action from the top-down in fact have a practical response to the creeping onset of Technogenic Climate Change.
My simple idea achieves a dual function: while it can help people lessen contributions to the onset of Technogenic Climate Change, it also can help alleviate personal participation in the maturing global dominance of “tech totalitarianism” (the global ubiquity of technology, tech gadgetry, and tech-driven consumer commerce) and help citizens carve out for themselves hours each day unalloyed with the imposed tyrannies and mandates of “mediated existence”.
“Mediated existence” is exactly what the name says: it is a human life divided into sequences of twenty-four hour days, eight of which optimally might be devoted to sleep, eight of which might be devoted to work/career/labor, and the remaining eight to alimentation and digestion, hygiene and personal grooming, tending to domestic and personal responsibilities and obligations, managing desired economic, social, political, physical, and spiritual affairs, and all other minutes and hours devoted to mediated existence by living passively in front of some kind of screen—participating in “life” via some appliance of mediation, “keeping in touch with the world” via some appliance of mediation . . . “living”, that is, one’s few remaining hours each day via some helpful, marketed, and sold (or subscription-supplied) appliance of mediation.
I call my simple proposal “Unplug-8”.
“Unplug-8” consists of the following: apart from c. eight hours of sleep per night (which is still possible without assistance from any mediating appliance) and apart from work or career (which entails obligatory interactions and interfaces with technologies of numerous kinds for various and numerous purposes), the meagre eight hours a day that any citizen has to call his or her own can be lived, whole and entire, without the first contribution of mediating devices and appliances.
In its extreme form, my simple notion means: unplug your mediating devices and appliances for the eight hours a day you might reasonably be permitted to call your own (or: unplug yourself from them). Do not use or consult your mediating devices for a full and entire eight hours a day: instead, live an unmediated life, an unmediated existence, in touch with the palpable reality of your immediate surroundings, your actual domicile (not the virtual one), your actual physical neighborhood (not your virtual neighborhood), in the city or rural setting where you actually dwell, in the actual hours of your actual life.
No doubt, many will shudder. “Detach myself from internet and cable and streaming fare? Rely on my own cognitive and sensory resources?” What fearful, dread, and daunting prospects!
—but be of good cheer: Unplug-8 is not proffered with any dogmatic or ethical imperative, and realism (even in an age of mediated human existence), when invoked, has to concede that few
will feel psychically fit or psychologically ready to undertake such an about-face. Unplug-8 has to be understood as a voluntary (but viable) option. Even if commitment to a full eight hours-a-day unplugged from mediating appliances and devices seems impractical, remember that mediated existence (with its ubiquitous and continuous commercial prodding and cajoling) is neither aesthetically attractive nor spiritually hygienic. At least at first, Unplug-8 can surely be practiced for just a portion of the eight hours out of twenty-four that modern allowances of “free time” permit: if not “Unplug-8”, then “Unplug-6”—if not “Unplug-6”, then “Unplug-4”, “Unplug-2”, or “Unplug-1”.
The facts remain: electronic technology proffered by its inventors, engineers, and marketeers has become so ubiquitous across the face of the entire planet as to begin to take on the aspect of “tech totalitarianism”. The prospects of mediated existence—run according to the schedules and calendars of tech tyrants—have begun turning the entire globe into a planetary, motor-driven treadwheel, in which all of us are acquiring the aspects of panting lab rats, racing in our endless circles, only to die of exhaustion at the very end of all our circular labors.
Unplug-8 is thus a sound response to both the advent of Technogenic Climate Change (less electricity consumption) and to whatever threats we may take to be posed by the rival advent of ubiquitous, global tech tyrannies. While “Unplug-8”, being voluntary, does not entail any ethical or dogmatic imperative of its own, it does give cause for pause and offers breathing room for harried humans who have been taught and trained to jump through the numerous colorful hoops of vacuous consumerism almost wholly for the sake of terrestrial consumer activity alone.
Unplug-8 at any level of adoption can offer small oases in the deserts of time and history for people to catch breath, to encounter ephemeral existence at least briefly without any interventions of mediation, and can permit moments for other reflections and thoughts on how we may want or care to live our short lives on this hurtling globe, no matter the future of tech tyrannies, no matter the extents of oncoming Technogenic Climate Change.
zebra says
Edward, alternatively, we might consider the lesson of that Buddhist monk in Tokyo… a very noisy location:
When he wanted to sleep, he would close the window.
When he wanted to practice meditation, he would open it.
Just sayin’ .
Sabine says
aka Edward Burke Roberts https://thewichitan.com/71975/op-ed/climate-change-guest-column-initial-responses-to-technogenic-climate-change/
Hi Ned. A bit too ‘flowery’ for my tastes. I prefer a direct communication style with the KISS principle.
Barton Paul Levenson says
Sorry for the double post.
glenm says
There is another paper on the AMOC shutdown/slowdown with estimates. It is an interesting read.
Probability Estimates of a 21st Century AMOC Collapse
Emma J.V. Smolders1*, Ren ́e M. van Westen1 and Henk A. Dijkstra1
Department of Physics, Institute for Marine and Atmospheric research Utrecht, Utrecht University, Princetonplein 5, Utrecht, 3584 CC, the Netherlands
https://arxiv.org/pdf/2406.11738
This paper is still going through the release process.
David says
Thank you glenm for the link. Yes, it is interesting and I found it worthwhile.
Further on the AMOC and the probability of when it may shutdown, I recently read a story at Wired (July 25th) about work of siblings Peter and Susanne Ditlevsen:
.
https://www.wired.com/story/amoc-collapse-atlantic-ocean/
Sabine says
By Gwynne Dyer
“By August, if we’re still looking at record-breaking temperatures, then we really have moved into uncharted territory,” said climate scientist Gavin Schmidt in April. Well, July 22 was the hottest average global temperature ever recorded — and July 23 promptly broke that brand new record. Here we are in August, and it is not looking promising.
Schmidt is director of NASA’s Goddard Institute for Space Studies. He was choosing his words very carefully when he used the phrase “uncharted territory,” because that is a frightening place to be.
Now, in one sense we have been in uncharted territory for several decades: our greenhouse gas emissions are driving global temperatures higher than anything we have experienced in the past. But at least we thought we had a map of our probable future.
https://www.thespec.com/opinion/columnists/climate-anomaly-puts-us-in-uncharted-territory/article_fcaa4e75-e3c6-5596-a3af-ea760b0e7ea2.html
Mal Adapted says
Bok:
The history of evolution on this planet through the long, looooong stretches of time, however, is a remarkable story. It’s like the earth KNEW that life in the universe was EXCEEDINGLY rare, so when it finally caught and lit it held onto that flame with a white knuckle grip, refusing to let go, protecting it from the winds of extermination even under the greatest of assaults: The hellish start of this rock. A snowball earth. Being repeatedly pummeled by meteors and asteroids. Five huge extinction events, (one wiping out 96% of life!). Through it all life changed and adapted and stubbornly continued.
That is poetic, my friend. Your choice of simile (“It’s like the earth knew”) over metaphor (The earth knew”) is appropriate. The imagery is explicitly teleological, however, which may be seductive to motivated cognition involving a deified Earth that actively wishes life’s continued existence. I know that’s not what you intend. Your comment is a good one IMHO. This is just an atheist’s observation about framing climate change as a political issue. Feel free to wax poetic (I know I do) whenever you think it will help us decarbonize ASAP, but please don’t give anyone a justification for collective inaction!
Geoff Miell says
On 2 Aug 2024, The Hamilton Spectator published an op-ed by Gwynne Dyer headlined Climate ‘anomaly’ puts us in uncharted territory. The piece included:
https://www.thespec.com/opinion/columnists/climate-anomaly-puts-us-in-uncharted-territory/article_fcaa4e75-e3c6-5596-a3af-ea760b0e7ea2.html
Is that by the beginning of Aug 2024 or the end, Gavin?
Has the Earth System now “moved into uncharted territory,” Gavin?
Kevin McKinney says
Gwynne, a Canadian journalist and writer originally specializing in military coverage, is a long-time observer and chronicler of the climate crisis, and I believe has several books on the topic. (I reviewed one myself quite a few years ago now, but I’ll spare you the link.) I recommend his work.
Secular Animist says
This is a problem:
“US politics is an outlier bastion of climate denial with nearly one in four members of Congress dismissing the reality of climate change … A total of 123 elected federal representatives – 100 in the House of Representatives and 23 US senators – deny the existence of human-caused climate change, all of them Republicans, according to a recent study of statements made by current members … The report defined climate deniers as those who say that the climate crisis is not real or not primarily caused by humans, or claim that climate science is not settled, that extreme weather is not caused by global warming or that planet-warming pollution is beneficial.”
https://www.theguardian.com/us-news/article/2024/aug/05/climate-change-denial-congress
Mal Adapted says
Thanks for the link, SA. These parts were also interesting:
We’ll find out whether denialists are punching above their weight this November. As the article notes, five years ago they were punching at or below their own weight. The IRA of 2022 passed with the narrowest of margins. The decline in affirmative denialism, popular and Congressional, is meliorative, at least. Not enough to matter if Republicans win control of either house, however.
Kevin McKinney says
Yes, the clear majority is more or less with mainstream science, yet this bogus “debate” continues.
Mal Adapted says
The Six Americas political evolution since 2009 is somewhat encouraging for decarbonization advocates (this one, at least). The numbers of disengaged, doubtful or dismissive Americans shrank by 5% of the total, while the percentage of us who are alarmed nearly doubled. I’m really curious about what accounts for those changed minds. The repeatedly record-breaking weather extremes of the past five years or so probably made a difference. The publicity around the IRA, as a relatively benign collective intervention, may have helped some deniers get past the argument from consequences. And we know younger people are more likely to acknowledge the urgency of collective action; maybe deniers are aging out of the voting population. OTOH, we also know carbon capitalists haven’t slackened their disinformation campaign, even while being hectored from unexpected quarters, not only on RC. A self-described “young conservative“, who wants the GOP to drop its long-standing climate-science denial plank, writes:
While skeptical of what “Conservative politicians” tell him, I’ll concede “it’s a bit more complicated than that.” This kid is non-dogmatic about climate change, but if he doesn’t vote for Harris/Waltz, he’s choosing the greater evil anyway. Still, maybe $trillions in annual profits actually can’t fool all the people all the time.
But just how complicated is it? This recent Nature Communications Earth & Environment article, The complexity of pluralistic ignorance in Republican climate change policy support in the United States, is intriguing. From the abstract:
IMO, the maintenance of that deceptive “information environment” reveals the continued, corrupting influence of fossil fuel producers and investors, who seek to thwart collective intervention in their revenue streams. What Is to Be Done? Collective decarbonization doesn’t mean Leninism, for cryin’ out loud! It does mean voting for Democrats in every election, at least until a (presumably young) Republican candidate openly supports collectively taking the profit out of selling fossil carbon.
Radge Havers says
Mal,
From the paper:
Interesting. I wonder about that. Supporting policies in theory wouldn’t necessarily equate to making them a priority even if the misperception of how many support those policies were removed. It’s easier to back burner climate if perceptions of more immediate problems loom disproportionately larger.
OTOH, perhaps a tipping point will be reached when people are more afraid of loosing their homes to fire. flood, etc. than they are of Democrats taking power and sucking the life out of their stupid culture wars and authoritarian impulses.
Radge Havers says
The code of silence…omertà?
Climate change deniers make up nearly a quarter of US Congress
Climate denialists – 23 in Senate and 100 in House – are all Republicans and make US an outlier internationally
https://www.theguardian.com/us-news/article/2024/aug/05/climate-change-denial-congress
Mal Adapted says
Radge:
“perhaps a tipping point will be reached when people are more afraid of loosing their homes to fire. flood, etc. than they are of Democrats taking power and sucking the life out of their stupid culture wars and authoritarian impulses.”
That’s what I’m hoping for. It wouldn’t take very many Republican voters reaching that point to flip the election.
“Climate change deniers make up nearly a quarter of US Congress
Climate denialists – 23 in Senate and 100 in House – are all Republicans and make US an outlier internationally
https://www.theguardian.com/us-news/article/2024/aug/05/climate-change-denial-congress”
Yes, that’s the article linked by Secular Animist, that launched this extended conversation!
Killian says
Turns out Greenland definitely melted out at least once during the Pleistocene, apparently around 416k-ish ybp. It’s commonly known – pick up any CO2 chart dating back 3 million years – CO2 was never above 300ppm or so.
And. Greenland. Melted. Out. Now, unless someone knows of some wild event that occurred around that time – a beach party by aliens, an asteroid nobody knows about, the gods being bored and playing with lazers, dragons on holiday – Greenland is done. It’s just a matter of time.
What now becomes the most important question to humanity is how quickly can the ice sheets stabilize after returning to 260 – 280 ppm? IIRC, a paper I read some years ago said they would **begin** to stabilize withing decades. Not very precise. I believe more recent findings indicated the same…?
So, THEN the question is, how quickly are we *willing* to act to cool the planet. I am certain we can be at negative emissions within five years. In theory, back at 300 ppm in as little as 20, but don’t get hung up on that. It’s BOE math in the best possible, absolutely perfect conditions. Still, 300ppm by 2050 or 2070 would be, frankly, easy with global buy-in.
Greenland guaranteed to go, and already going. That means WAIS along with it, no doubt. AMOC tipping between any time now and 2070.
Time? There is none. Anyone ready for a real discussion of regenerative futures, or y’all wanna figure out where to relocate the entire equatorial population and the entire coastal population of the planet all while trying to keep from dying of flood, famine, storms, heat or unrest?
https://www.barrons.com/news/greenland-fossils-reveal-greater-sea-level-threat-from-climate-change-2ca1bd94
Geoff Miell says
Killian: – “Greenland is done. It’s just a matter of time.”
It depends on how long the atmospheric GHG concentrations stay above Holocene levels.
On 22 August 2022, at the Cryosphere 2022 Symposium at the Harpa Conference Centre Reykjavik, Iceland, glaciologist Professor Jason Box said from time interval 0:15:27:
“And at this level of CO₂, this rough approximation suggests that we’ve committed already to more than 20 metres of sea level rise. So, obviously it would help to remove a hell-of-a-lot of CO₂ from the atmosphere, and I don’t hear that conversation very much, because we’re still adding 35 gigatonnes per year.”
https://www.youtube.com/watch?v=iE6QIDJIcUQ
That suggests:
* the Greenland Ice Sheet goes;
* the West Antarctic Ice Sheet goes;
* Himalayan, European, North American, Russian, Scandinavian, South American, etc. glaciers & mountain ice caps go;
* some parts of the East Antarctic Ice Sheet go.
That process will likely take centuries/millennia, but the first metre of sea level rise (SLR) will be catastrophic for many coastal properties/infrastructure around the world. I’d suggest multi-metre SLR is highly likely before 2100.
Glaciologist Prof Jason Box talks with John Englander re is Greenland beyond its tipping point?
https://www.youtube.com/watch?v=8jpPXcqNXpE
Nigelj says
GM. Something relevant from Science Daily, August 5th 2024: ” Greenland fossil discovery reveals increased risk of sea-level catastrophe……Seeds, twigs, and insect parts found under two miles of ice confirm Greenland’s ice sheet melted in the recent past, the first direct evidence that the center — not just the edges — of the two-mile-deep ice melted away in the recent geological past. The new research indicates that the giant ice sheet is more fragile than scientists had realized until the last few years — and reveals increased risk of sea-level catastrophe in a warmer future…..”
https://www.sciencedaily.com/releases/2024/08/240805164411.htm
nigelj says
Geoff Miell. I largely agree with your comments on SLR.
The IPCC say SLR of 2 metres is possible this century if warming gets above 2 degrees. This appears to be due to the possibility of a physical destabilisation of ice sheets a process which could last a few centuries. This would obviously be catastrophic for coastal communities and will result in lots of abandoned infrastructure.
There have been periods in the past where SLR has been well over 2 metres per century, such as meltwater pulse 1a. So its not unprecedented. There was more ice back then to melt, but it looks to this non exxpert like we could still trigger something near 2 metres this century and next.
https://en.wikipedia.org/wiki/Meltwater_pulse_1A
There have also been periods in the past where ice sheets melted by many metres, taking several millenia to melt, at around 0.5M or less per century. I would say the loss of coastal land would be slower than 1-2 M per century, but would ultimately still be huge, and adaptation will have a significant cost.
Geoff Miell says
nigelj: – “There have also been periods in the past where ice sheets melted by many metres, taking several millenia to melt, at around 0.5M or less per century.”
In the scientific journal Atmos. Chem. Phys., 16, 3761–3812, 2016, there’s a paper by James Hansen et al., titled Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous, which included (on page 3766):
https://acp.copernicus.org/articles/16/3761/2016/acp-16-3761-2016.pdf
It seems around 5 m of SLR has previously occurred within a timescale of a century according to the paleo-record, and the current climate forcing is more rapidly growing than at any time in the paleo-record, so I’d suggest it’s not unreasonable to expect a similar accelerating multi-metre SLR within this century.
Real-world ice melt will not follow a smooth curve.
The acceleration of the rate of SLR will continue while ever the energy inputs into the Earth System, and more particularly into the cryosphere and oceans, increase.
With a rate of SLR currently at around 5 mm/y in 2024, looking at the next 50 year duration for the following scenarios:
* A 7-year doubling scenario curve exceeds 1 m around 2055 and 2 m around 2061;
* A 10-year doubling scenario curve exceeds 1 m around 2063 and 2 m around 2072;
* A 13-year doubling scenario curve exceeds 1 m around 2070.
The 10- & 13-year doubling curves sit within the upper end of the global mean SLR projection range 0.15 to 0.43 m by 2050 in Table 3.2 in NOAA’s Feb 2022 report on SLR.
https://oceanservice.noaa.gov/hazards/sealevelrise/sealevelrise-tech-report.html
I’d suggest lethal humid heat and worsening global food security are likely to be critical factors that will be more pressing for most locations (compared with the consequences of accelerating SLR) within the next few decades.
MA Rodger says
Geoff Miell,
I have to call you out on your use of the NASA Feb 2022 report to support a +5m 2100 Global SLR projection. Note the table in that report is Table 2.3 not Table 3.2. And that Table 2.3 shows 2100 SLR projections of +0.3m to +2.0m. So not +5m, while that same Feb 2022 NASA report states:-
The idea of there being a doubling-period for SLR driven by polar ice-loss was an interesting idea a decade-back when the evidence of polar ice-loss (GRACE) was showing that such a doubling may have been occurring. Back then, there was still no discussion of the issue of how such a doubling could be sustained with the massive annual melt-rates required to achieve a +5m SLR by 2100 and Hansen et al (2016) which you reference did address that issue. But the exponential ice-loss was looking less evident in GRACE by 2016 and today even more so, with GRACE-FO data showing the average 2002-23 polar ice- loss of 355Gt/yr (= SLR component of +1.0mm/yr) and the recent-years data showing 70% of that ice-loss (80% since GRACE-FO became operational).
I’m pleased to see the Feb 2022 NASA report does present the “when, not if” concept for future SLR but it is rather well buried which, along with the “committed sea level over the next 2000 years” that defines the “if”, is a message requiring a lot more attention (rather than this ‘SLR by 2100’ messaging).
Sabine says
Rodger incorrectly claimed – “to support a +5m 2100 Global SLR projection. ”
Neither Geoff or his references suggested any projection anything like that. It’s a bad illogical strawman argument. Read what Geoff wrote again much more carefully, and then get back to Logic and the actual Data involved in that comment and refs.
I cover these kinds of issues about errors here just the other day:
How I lost trust in scientists
Sabine Hossenfelder
https://www.youtube.com/watch?v=gMOjD_Lt8qY
Geoff Miell says
MA Rodger (at 10 Aug 2024 at 5:16 AM): – “I have to call you out on your use of the NASA Feb 2022 report to support a +5m 2100 Global SLR projection.”
It’s interesting that you refer to the NOAA (NOT NASA, although NASA, US EPA, USGS, US Department of Homeland Security, FEMA, US Army Corps of Engineers, Rutgers University & FIU are listed as contributors) Feb 2022 report but completely dismiss the Hansen et al. (2016) paper reference. Is that inconvenient for your narrative perhaps, MA Rodger?
Thank you for highlighting my typo – “Note the table in that report is Table 2.3 not Table 3.2.”
You refer to the NOAA Feb 2022 report statement:
It may well be considered “less plausible” by NOAA at this time, but that does not mean it’s IMPOSSIBLE. The paleo-record indicates it has been possible in the past, per my reference to the Hansen et al. (2016) paper. I’d suggest it would be very foolish to ignore history. This suggests to me NOAA is perhaps engaging in “scholarly reticence.”
Professor Jason Box says in the YouTube video from time interval 0:01:50 (bold text my emphasis:
“Now if climate continues warming, which is more than likely, then the loss commitment grows. My best guess, if I had to put out numbers; so by 2050, 40 centimetres above 2000 levels; and then by the year 2100, 150 centimetres, or 1.5 metres above the 2000 level, which is something like four feet. Those numbers follow the dashed-red curve on the IPCC’s 6th Assessment, which represents the upper 5-percentile of the model calculations, because the model calculations don’t deliver ice as quickly as is observed. If you take the last two decades of observations, the models don’t even reproduce that until 40 years from now.”
https://www.youtube.com/watch?v=8jpPXcqNXpE
Ice loss observations are well in advance of what most of the modelling suggests.
Per the WMO’s State of the Global Climate 2023, on page 6:
* From Jan 1993 to Dec 2002, the average rate of SLR was 2.13 mm/y;
* From Jan 2003 to Dec 2012, the average rate of SLR was 3.33 mm/y; and
* From Jan 2014 to Dec 2023, the average rate of SLR was 4.77 mm/y.
https://wmo.int/publication-series/state-of-global-climate-2023
Thus global mean sea levels since the beginning of year-2000 to the end of year-2023 have risen:
(3 x 2.13 mm) + (10 x 3.33 mm) + (10 x 4.77 mm) = 87.39 mm
For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 156.7 mm (or 244.1 mm SLR relative to the Jan 2000 level)
2050: 383.0 mm (or 470.4 mm SLR relative to the Jan 2000 level)
2060: 835.7 mm (or 923.1 mm SLR relative to the Jan 2000 level)
2070: 1741.0 mm (or 1828.4 mm SLR relative to the Jan 2000 level)
For a 13-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 134.7 mm (or 222.1 mm SLR relative to the Jan 2000 level)
2050: 293.9 mm (or 381.3 mm SLR relative to the Jan 2000 level)
2060: 565.2 mm (or 652.6 mm SLR relative to the Jan 2000 level)
2070: 1027.6 mm (or 1115.0 mm SLR relative to the Jan 2000 level)
Prof Jason Box’s comments referred above suggests to me that the SLR rate doubling time for the period from now to year-2050 is likely somewhere between 10- and 13-years.
Whether the doubling time process continues through to 2100 remains to be seen. I’d suggest it’s heavily dependent on whether we/humanity can rapidly reduce GHG emissions from now on, or not, and begin large-scale atmospheric carbon drawdown.
I’d suggest what looks increasingly likely is that SLR will exceed well over 1 metre relative to year-2000 levels by year-2100. That will be undeniably catastrophic for many coastal properties and infrastructures. Whether SLR reaches 1.5 m or 2.0 m or significantly more by 2100 is academic – societal chaos has already well and truly ensued.
MA Rodger (at 10 Aug 2024 at 5:16 AM): – “But the exponential ice-loss was looking less evident in GRACE by 2016 and today even more so, with GRACE-FO data showing the average 2002-23 polar ice- loss of 355Gt/yr (= SLR component of +1.0mm/yr) and the recent-years data showing 70% of that ice-loss (80% since GRACE-FO became operational).”
Ice loss is not the only contributor to SLR. Oceans are warming too and thus expanding.
https://climatereanalyzer.org/clim/sst_daily/
https://www.unsw.edu.au/newsroom/news/2024/01/how-rising-sea-levels-will-affect-our-coastal-cities-and-towns
MA Rodger says
Sabine,
I actually watched your ‘How I Lost Trust in Scientists’ video a few days back, (and more recently your John Clauser debunking).
I think I was a bit disappointed that the ‘How I Lost Trust in Scientists’ message set the climatology of climate change alongside ESP research and the researches of theoretical physics. So initially I worried where your message was going, especially with it giving the view that financial self-interests (mostly) is what drives the ‘physics’ problem. My experience (in other fields of academia) suggest it is otherwise (not financial), more about a researcher’s reluctance to divert off a slippery slope that has lead them somewhere with its bitter blasting of reality nobody explained existed. Indeed, the public message they probably initially heard-given was likely the opposite. As you later say, the situation is “baked into the current system.”
And this led on to your video stating that climate change is worse than a hoax, which was sounding really ultra-controversial.
But this ‘worseness’ you describe as being climatology underestimating the rate of warming and also underestimating the uncertainty. So I see little controversy, that is unless the ‘rate’ and the ‘uncertainty’ are seen as extreme (like 5m SLR by 2100 – “It seems around 5 m of SLR has previously occurred within a timescale of a century … so I’d suggest it’s not unreasonable to expect a similar accelerating multi-metre SLR within this century.”).
And having myself followed the climate change science for a quarter of a century and been bashing on about it for a lot longer, I would say that the “baked into the current system” problem doesn’t really exist within the climatology. The problem was/is how to turn messages like ’emissions must certainly peak before 2020′ and ‘climate change is a planetary experiment we need to stop’ into the political actions to cut emissions.
MA Rodger says
Geoff Meill,
NOAA not NASA. My bad!!
But you should know by now why I find Hansen et al (2016) problematic, and should know it is not the same as a ‘complete dismissal.’ As I have been saying for many a year, a potential multi-metre SLR by 2100 comes down to ice dynamics. So I do pay attention to the likes of Jason Box as well as GRACE-FO data.
Your stopping your up-thread SLR projections at +1m and +2m falls into the same trap as IPCC projections stopping at 2100. The rate of SLR will keep going at the same rate for a long time after. To prevent this will require cooling the planet down significantly.
Projecting your 10-yr or 13-yr doubling of SLR from your start-conditions gives a 2100 SLR of +15m and +6m respectively. And with a linear rise adopted past 2070, that would be a 2100 SLR of +6m and +4m respectively.
Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward and in my mind a whole different subject. And additionally, whether we reach global averaged SLR of +2m by 2100, 2200 or 2300 makes it all a bit academic.
In the short-term SLR does indeed result from thermal expansion as the biggest contributor (comprising perhaps 39% of 2006-18 SLR obs according to Slangen et al 2022) with non-polar ice also shown a big player (20%) as is land water (16%). That leaves smaller contributions for Greenland (14%) and Antarctica (11%). But the potential for multi-metre SLR rests solely with the polar ice caps.
IPCC AR5 WG1 Fig 13.14 shows a thermal expansion contribution of +0.42m/ºC after 2,000 years, non-polar ice fully melting out with a total potential contribution of perhaps +0.5m and presumably we won’t feel the need to pump out so much of the 44M Gt(H2O) estimated in various aquifers globally by Ferguson et al (2023) (thus with a potential +125m SLR if we managed to pump out the lot). IPCC AR5 puts Antarctica with a contribution of +1.2m/ºC and Greenland perhaps +0.5m/ºC with an added 5m when it becomes unstable and melts down.
So, while “ice loss is not the only contributor to SLR,” it is the overwhelming cause of SLR going multi-metre.
Geoff Miell says
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “But you should know by now why I find Hansen et al (2016) problematic…”
Jealously perhaps?
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “Your stopping your up-thread SLR projections at +1m and +2m falls into the same trap as IPCC projections stopping at 2100.”
Predicting the longer-term future is a fools errand – far too many variables.
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “The rate of SLR will keep going at the same rate for a long time after.”
Will it? It depends on whether we/humanity can rapidly reduce human-induced GHG emissions AND begin large-scale atmospheric carbon drawdown to start returning the Earth System back to Holocene conditions, or not. Per Jason Box, the current GHG levels commit the Earth System to more than 20 m of SLR. As I stated in an earlier comment:
MA Rodger (at 12 Aug 2024 at 8:26 AM): – “Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward…”
According to sea level rise projections, nearly one billion people will be exposed to much greater risks of flooding by mid-century. Is that not “catastrophic” enough for you, MA Rodger?
https://earth.org/sea-level-rise-projections/
Here’s an example. The UAE has almost completed a 4-nuclear reactor project at Barakah, on the shores of the Persian Gulf. Per the IAEA’s PRIS database:
Reactor Unit _ Net Capacity (MWₑ) _ Start Construction _ Grid Connect _ _ Full Ops
BARAKAH-1 _ _ _ 1,337 _ _ _ _ _ _ _ _ _ _ 19 Jul 2012 _ _ _ _ 19 Aug 2020 _ _ 01 Apr 2021
BARAKAH-2 _ _ _ 1,337 _ _ _ _ _ _ _ _ _ _ 15 Apr 2013 _ _ _ _14 Sep 2021 _ _ 24 Mar 2022
BARAKAH-3 _ _ _ 1,337 _ _ _ _ _ _ _ _ _ _ 24 Sep 2014 _ _ _ 08 Oct 2022 _ _ 24 Feb 2023
BARAKAH-4 _ _ _ 1,310 _ _ _ _ _ _ _ _ _ _ 30 Jul 2015 _ _ _ _23 Mar 2024 _ _ Pending
https://pris.iaea.org/PRIS/CountryStatistics/CountryDetails.aspx?current=AE
The APR-1400 reactors have a design lifetime of 60 years (per WNISR-2023, page 72), with the possibility of a life extension for a further 20 years. That means it’s possible the Barakah Nuclear Power Plant may still be operational beyond 2100 (if civilisation doesn’t collapse before then).
https://www.worldnuclearreport.org/-World-Nuclear-Industry-Status-Report-2023-.html
Per Climate Central’s Coastal Risk Screening Tool, the Barakah Nuclear Power Plant site appears to be at risk of inundation beginning from around 1.0 m of SLR. It gets much worse at 2.0 m SLR, with all four reactors at risk. And most of the site is inundated at 3.0 m of SLR.
https://coastal.climatecentral.org/
Some examples at 1.0 m SLR:
* the Mekong River delta is inundated;
* the northern end of the 16R/34L runway of Sydney Airport (SYD) is inundated;
* Bangkok City is inundated;
* Amsterdam City is inundated;
* Ho Chi Minh City is inundated;
* Hamburg City is at risk.
I’d suggest 1 m of SLR is more than enough to cause chaos/catastrophe for many coastal and estuary locations around the world. Add periodic storm surges on top of that and more locations are impacted. That’s likely billions of lives disrupted directly or indirectly.
Piotr says
MA Rodger 12 Aug “But you should know by now why I find Hansen et al (2016) problematic…”
Geoff Miell 13 Aug : “Jealously perhaps?”
Really? That’s what you understood from MAR posts on the subject???
MA Rodger: “Identifying what level of SLR becomes ‘catastrophic’ in some manner is not at all straightforward and in my mind a whole different subject”
Geoff Miell According to sea level rise projections, nearly one billion people will be exposed to much greater risks of flooding by mid-century. Is that not “catastrophic” enough for you, MA Rodger?
Have you even read MAR’s sentence before you blew your top, Geoff Miell?
And if _that_ is your response to MAR, I shudder to think how would you treat a guy who called the threat of SLR …. “less pressing”.
“ I’d suggest lethal humid heat and worsening global food security are likely to be critical factors that will be more pressing for most locations (compared with the consequences of accelerating SLR) within the next few decades
Geoff Miell, Aug. 8.
Paul Pukite (@whut) says
MA Rodger said:
That’s not the Sabine you think it is.
MA Rodger says
Paul Pukite (@whut),
This was explained by ‘our’ Sabine. Due to “a typo” apparently.
Killian says
Geoff: Yeah, all the points you made were rather clearly made in the OP. There’s no point in discussing stabilizing the ice sheets if it can’t be done… right? And, clearly, if Greenland has melted out, so will everything else be melting. Common knowledge, so no need to specify.
Yes, SLR of at least 1M+ by 2100 is now concensus. I said it over 15 years ago (at least one meter, two likely, 3 possible. Science says 5 is possibe) so… again… no need to specify/repeat the obvious.
I don’t like writing long posts. Eschewing the obvious helps keep them short.
Nigel: You realize that is about the paper I posted… yes? Clear communication would be, “Here’s an articl about the linked paper.”
Secular Animist says
Killian wrote: “Anyone ready for a real discussion of regenerative futures”
Please consider discussing your ideas about regenerative futures with those who are in a position to actually do something about it. Arguing about your ideas with the half-dozen people who read this blog is unlikely to accomplish anything.
David says
Talk about an interesting way a group of scientists at a Swiss climate research institute are using in the development of a proxy to estimate regional temperature data going back hundreds of year (to 1390) using wine-making records of European (French) vineyards! The following is the story by Christer Watson in the Fort Wayne Indiana newspaper The Journal Gazette (published August 6th):
.
https://www.journalgazette.net/opinion/columnists/a-must-read-wine-making-records-yield-climate-change-confirmation/article_2b5e1dd2-5324-11ef-94e4-8f408990cf4f.html
.
Have no idea regarding the validity of the endeavor, but I give full marks for creative thinking.
MA Rodger says
David,
I’ve not met before the block down a link that I meet down that ‘Journal Gazette’ link you present.
“451: Unavailable due to legal reasons = We recognize you are attempting to access this website from a country belonging to the European Economic Area (EEA) including the EU which enforces the General Data Protection Regulation (GDPR) and therefore access cannot be granted at this time.”
This restriction appears to have been set by the ‘Journal Gazette’ itself.
So I will have to assume the work being discussed down the ‘unavailable’ link is this one – Pfister et al (2024) ‘600 years of wine must quality and April to August temperatures in Western Europe 1420–2019’, although earlier similar works involving the lead author include Labbé et al (2019) ‘The longest homogeneous series of grape harvest dates, Beaune 1354–2018, and its significance for the understanding of past and present climate’.
Of course the most adventurous use of historic record-keeping as temperature proxies is that using the Japanese cherry blossom records which run back twice as long.
David says
MA Rodger,
Thank you for your enhancement. My Journal Gazette article fails to provide links or any info on the scientists (no names), with only a reference of the work coming out of a “Swiss climate research institute.” After checking the reference links you provide, I believe you are spot on that it’s Pfister et al (2024) that the Gazette story is about.
So between the above and the work involving Japanese cherry blossoms you reference, I can learn a bit about the science and methods that allow for the development of this type of proxy. Which I will enjoy!
Kevin McKinney says
Oh, almost forgot–if the short music video is a viable cultural form for you, or someone you know, you might be interested in checking this one out. It’s ironically titled–Drill, baby, drill!–uses an (involuntary) audio sample from He Who Shall Not Be Named, and, if I may immodestly say so, has received some praise from early listeners.
https://www.youtube.com/watch?v=k-t_WoKmsK8
“Vote climate!”
Barton Paul Levenson says
Awesome video. Thanks.
Kevin McKinney says
Thanks, Barton!
MA Rodger says
Copernicus ERA5 has reported for July with a global anomaly of +0.68ºC, a small increase on the June anomaly (+0.67ºC) [& also a tad above both April (+0.67ºC) & May (+0.65ºC)]
As expected July 2024 did come in below the July 2023 anomaly (+0.72ºC) making an end to the run of thirteen “scorchyisimo!!!” hottest ‘This Month’s on record.
Yet we may be in for another “scorchyisimo!!!” month in August.
Copernicus ClimatePulse daily data shows the cooling from the ‘bananas’ anomalies of the last third of 2023 (averaging Sept-Dec +0.87ºC) has been taking a bit of a holiday at the moment. And with the early-days of August averaging +0.78ºC, somewhat higher than the anomaly for August 2023 (+0.71ºC), we could be seeing a “scorchyisimo!!!” August 2024 if the rest of this month averages don’t cool below +0.69ºC.
If the cooling doesn’t resume, maybe calling this pause in the cooling-off “a bit of a holiday” is wrong.
(The Uni of Maine Climate Reanalyser, which appears a few days in arrears of ClimatePulse, shows the Southern Hemisphere has been the cause of recent global “scorchyisimo!!!” days although the NH has been ‘holidaying’ itself. For a nerd-eye’s view, see graphics showing global NH & SH ERA5 5-day traces ‘First Posted 15th Dec 2023’)
And even an extended “holiday” could be enough to see the full calendar year of 2024 make ‘Hottest Year on Record’. The data Jan-Jul shows this would require Aug-Dec 2024 to average above +0.46ºC (Previous years have seen Aug-Dec average 2023 +0.84ºC, 2019 +0.43ºC, 2015 +0.38ºC, 2016 & 2020 +0.37ºC, 2021 +0.36ºC.) and less cooling is starting to look a bit more likely as the cooling in NINO3/4 did itself take a bit of a holiday through July, reducing the strength/likelihood of the coming predicted La Niña, this apparently “a notable difference.” And it would be an arriving La Niña that would be bringing the cooling required to head-off a “scorchyisimo!!!” 2024.
Barry E Finch says
Lazy Summer cut’n’paste about Science Censorship (which an Expert Googleologist pointed out at me on Realclimate is only caused by my linked adverts to Eaton’s catalogue ladies’ lingerie Section, hey I get a stipend). The following might slip past the Ginormous Realclimate Censorship Bureaucracy caught napping in Summer though. https://www.youtube.com/watch?v=oqu5DjzOBF8 @grindupBaker Well, either this video is my Final Refuge for offering high-quality science assertions for others to comment on, refute with good science, or whatever they want, usually verifiable from me by scientific consensus, or else my own accepted physics & logic, or if not my Final Refuge any more then I have no Refuge for disseminating high-quality science because the old reliable “potholer” has “gone bad” on me, Censoring the Living Crap out of my high-quality science and asking me questions to which my accurate replies are Censored never shown to anybody.
From https://www.youtube.com/watch?v=HhAX42dT09w
@grindupBaker Potholer’s statement at 16:40 to 16:44 is factually incorrect. Here’s assessed science. Ice sheets & vegetation changes albedo-change feedback caused most of the warming, an humongous +ve feedback. The proportions of the things that warmed Earth by 7.45 degrees from the last glaciation period (colloquial “ice age”), warming from 17,300 to 6,000 years ago are:
0.5 +- 1 w/m**2 8% Milankovitch cycles orbital eccentricity, axial tilt & precession of the equinoxes changes
forcing (what pulled the trigger that started it)
3.5 +- 1 w/m**2 53% ice sheets & vegetation changes albedo-change feedback
1.8 +- 0.3 w/m**2 27% CO2 change feedback
0.4 +- 0.1 w/m**2 6% CH4 change feedback
0.4 +- 0.1 w/m**2 6% N2O change feedback
:::::::::::::::::::::::::::::::::::::
6.6 +- 1.5 w/m**2 total
As you see the massive ice sheets & vegetation changes albedo-change feedback was 2.0 times as much effect as the CO2 (and there was also CH4 & N2O effect to consider). That 6.6 w/m**2 of total imbalance plus water vapour & cloud feedbacks is what increased Global Mean Surface Temperature (GMST) by 7.45 degrees from the depths of the glaciation period “Ice Age” 17,300 years ago to the Holocene Optimum 6,000 years ago, which is a factor of 7.45 / 6.6 = 1.13 degrees per w/m**2 whereas I got my 0.97 degrees per w/m**2 over 2,000 years above from 25 separate proxies of the massive PALEOSENS project (not just from 1 de-glaciation).
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@Leafsdude Sources, please.
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@jaykanta4326 Nothing you brought was actual science, no matter what you think.
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@grindupBaker @Leafsdude I’m being massively censored as always since 2022 but I’ll put this reply in my notes and maybe try again some place some time. It is at 8:00 at https://www.youtube.com/watch?v=KTTlAAiwgwM Acknowledge this information.
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@potholer54 @grindupBaker — Thanks for taking the time to lay all this out. But really, I’m not the one you should be talking to. I showed the relevant studies in the video, so perhaps you could talk to the authors.
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You will not see my information “Sources” to @Leafsdude because my comment above is Censor-Deleted by GoogleyTubes (as per >70% for my science comments) or “potholer”.
And I am now in the Kafkaesque situation of being advised by random half wits that “Nothing you brought was actual science” because I quoted a “James Hansen” in talk he gave at American Geophysical Union (AGU). Hilarious.
Barry E Finch says
If anybody has the knowledge please correct my placeholder “1,500” below or point to something definitive that I ‘d get that from with <3 hours effort (Or tear my entire babble into shreds if you're really challenged to fill the hours in the day).
So-called "greenhouse effect" physics: It happens in Earth's troposphere. The H2O gas & CO2 in Earth's atmosphere manufacture ~1,500 times as much radiation as the Sun's radiation that Earth absorbs (or something of that scale, hundreds of times as much). Taking 1 Unit as the Sun's radiation that Earth absorbs (which is 99.93% of all energy going into the ecosphere, geothermal and all the human nuclear fission and fossil carbon burning are 0.035% each) and the 1,500 times as a workable example (not accurate) to describe the physics concept:
==== Atmosphere energy (as power) Budget ====
Units
0.33 Solar SWR that Earth absorbs into the atmosphere
1,500 LWR manufactured by H2O gas & CO2 molecules in Earth's atmosphere, using up 1500 "heat" Units
1,497.65 LWR absorbed by H2O gas & CO2 molecules in Earth's atmosphere, generating 1,497.64 "heat" Units
0.92 LWR Leaks out the top of Earth's atmosphere and goes to space
1.43 LWR Leaks out the bottom of Earth's atmosphere and goes into the surface
1.57 LWR Leaks out the surface and goes into the bottom of Earth's atmosphere
0.45+x "Heat" (regular+water evaporation latent) rises from the surface into the troposphere at a range of altitudes
x "Heat" (regular+water condensation latent) goes from the troposphere at a range of altitudes into the surface
==== Surface energy (as power) Budget ====
Units
0.67 Solar SWR that Earth absorbs into the surface
1.43 LWR Leaks out the bottom of Earth's atmosphere and goes into the surface
1.57 LWR Leaks out the surface and goes into the bottom of Earth's atmosphere
0.45+x "Heat" (regular+water evaporation latent) rises from the surface into the troposphere at a range of altitudes
x "Heat" (regular+water condensation latent) goes from the troposphere at a range of altitudes into the surface
0.08 LWR Leaks out the surface and goes to space
————–
LWR straight from the surface to space is because H2O gas, CO2, CH4, O3, NOx, CFCs don't absorb those wavelengths
Earth makes LWR & SWR photons from the centre of Earth's core to the top of Earth's atmosphere (it's all various atoms & molecules making it) in an amount of several hundred billion of those Units above, an amount of several hundred billion times as much as the Sun's radiation that Earth absorbs. It can't much get out to space though because practically the exact same amount of photons several hundred billion times as much as the Sun's radiation here also gets absorbed by the same, or other, atoms & molecules by the time it's travelled a few microns in solids & liquids, or travelled metres in troposphere gases, or travelled metres to kilometres in stratosphere gases and higher, being converted when it's absorbed into causing faster atom or molecule speed, kinetic energy (which is what's commonly called "heat").
————–
So there's the balance at the top-of-atmosphere (TOA) with 1 Solar SWR Unit being absorbed below and 0.92+0.08=1 LWR Unit being sent through the TOA to space. The "greenhouse effect" is the fact that only 0.92 leaks out the top of Earth's atmosphere but a larger 1.43 leaks out the bottom of Earth's atmosphere into the surface, because only the leakage to space gets rid of the constant stream of solar SWR energy, not the leakage into the surface. If they were both the same, both 1.175, then there'd still be 2.35 leaking out of Earth's atmosphere but there'd be no "greenhouse effect" (as you see, out of the top of Earth's atmosphere to space has gone up from 0.92 to 1.175 so there's obviously much more cooling). The reason why they are unbalanced with more leaking out the bottom than out the top is simply because Earth's troposphere is usually by far (much) colder at the top than at the bottom and colder gases make less radiation than warmer gases because they collide less frequently and with less force (that's what "colder" means, it's just molecules bashing other molecules less frequently and with less force).
——
If more H2O gas & CO2 molecules are added into Earth's troposphere then the 0.92 that leaks out the top of Earth's atmosphere is reduced and the 1.43 that leaks out the bottom of Earth's atmosphere is correspondingly increased. For example, add some ghg molecules for a 0.01 Unit effect and the 0.92:1.43 leakage changes to 0.91:1.44 leakage, so there's more "greenhouse effect". That 0.01 Unit example is a "forcing" of 2.4 w/m**2 which is 60 years of the current ghgs increase and is expected would warm by ~2.4 degrees with the feedbacks.
Barton Paul Levenson says
BEF: So-called “greenhouse effect” physics: It happens in Earth’s troposphere. The H2O gas & CO2 in Earth’s atmosphere manufacture ~1,500 times as much radiation as the Sun’s radiation that Earth absorbs (or something of that scale, hundreds of times as much).
BPL: No, that doesn’t sound right at all. The greenhouse radiation received at Earth’s surface is about 384 watts per square meter, while the solar illumination at the surface is 188 W/m^2. Around twice as much, not 1500 times as much.
Barry E Finch says
BPL As clearly indicated in my table the “1,500” approximation, placeholder quantity though it be, does not refer to the relatively-minuscule leakage of LWR from bottom (your quantity) nor from top of atmosphere but to the TOTAL photons manufactured in the troposphere. Obviously, the TOTAL photons manufactured would only be of similar quantity to the leakage if the IR gases absorbed hardly any photons, which I don’t think is the case. In fact I clearly suggested for Scale only that something of order 1,000 times as much photons or photon energy gets manufactured as the portion that gets past other molecules (not absorbed) and makes it out of the top or bottom of the air. I thought it was absolutely crystal clear and not subject to any misinterpretation. I’m quite perplexed as to how I’m misphrasing it because it seems so trivially simple to me. Which is to say that it might be correct, what is happening, or incorrect, not what is happening, but either way it seems to me trivially obvious and crystal clear what I’m asserting (Right or Wrong). I’m at a loss.
Kevin McKinney says
Like BPL, I found your formulation not so crystal clear. (And by the way, when I was writing my Doctoral dissertation, I had your experience vis a vis my advisor. It was a painful experience, but it did help my prose, as to this day I try to remember to simplify my sentence structure and make references more explicit, to ease the reader’s mental workload.)
But perhaps I’m starting to get it. Let’s see.
Approaching it by way of the old bathtub analogy, insolation and upwelling LWR (etc.) absorbed by the atmosphere correspond to the water coming from the faucet; LWR emitted to space (etc.) correspond to the water going down the drain; and your placeholder “manufactured photons” correspond to the water sloshing around the tub.
Accurate, or mostly accurate?
Barton Paul Levenson says
I think my 384 W/m^2 figure is too high. Other sources give 333.
patrick o twentyseven says
I thought B.E. Finch’s comment was clear: he’s referring to the total rate at which energy is being emitted as photons, within the whole volume (or mass) of material. It is a flux that is not directional through space …
(photons are generally emitted equally in all directions (absorption cross sections are generally isotropic in the atmosphere – aside from eg. certain ice crystals which drift with preferred orientations – although perhaps if we count all emissions within the ice and not just those which emerge from surfaces… oh, wait, crystals can have anisotropic properties…)
… but a flux through form (from internal energy (of atoms/molecules/electrons/etc.) to radiant energy (photons)).
We could consider this to be the “gross radiant cooling”, where net radiant cooling is that minus the rate of absorption of photon energy. Aside from variations in temperature, and Planck function (Bν) over the spectrum**, Gross radiant cooling per unit mass is proportional to opacity**** – ie, the mass absorption coefficient = k_a ,– ie, contributions from different materials add linearly, each contribution is proportional to the relative concentration of material (***relative to total mass of a volume).
——————— ———————
**,**** – setting aside stimulated emission. stimulated emission ÷ direct absorption = function of temperature …
(assuming LTE, or at least LEDNLIE (Local Equilibrium Distribution of Non-Latent Internal Energy, my own acronym))
… (off the top of my head, I think it’s exp[-E/(kT)] ),
both proportional to ambient radiances, so it’s convenient to combine them into a sort of net absorption (proportional to 1 − exp[-E/(kT)] ), which is what absorption cross sections and absorption coefficients account for: the absorption cross section σ_a is the area which would net-absorb the intensity (= radiance * area facing a direction) that a unit of material absorbs.
Spontaneous emission is still accounted separately, as the emitted intensity (= radiance * area facing a direction) filling the opaque σ_a; this is also proportional to exp[-E/(kT)] … and a function of the spectrum, and (n_{r})²= the square of the real component of the index of refraction (for isotropic materials; idk about anisotropic materials …) – fitting this into the area σ_a gives radiance = Bν
https://en.wikipedia.org/wiki/Planck%27s_law
(proportional to
exp[-E/(kT)] ÷ ( 1 − exp[-E/(kT)] )
= 1 ÷ ( exp[+E/(kT)] – 1 )
)
(Given Planck function formulas tend to exclude a factor (n_{r})² because n_{r} = 1 is assumed (at least approx.))
… and so the visualization of (for isotropic absorption) incandescently-glowing perfect opaque blackbody spheres (same radius as circle which has area σ_a) representing absorption and emission per unit material, in average effect.
https://en.wikipedia.org/wiki/Maxwell%E2%80%93Boltzmann_statistics
——————— ———————
https://en.wikipedia.org/wiki/Optical_depth
https://en.wikipedia.org/wiki/Attenuation_coefficient#Absorption_and_scattering_coefficients
https://en.wikipedia.org/wiki/Absorption_cross_section
Gross radiant cooling per unit mass by gases is spectrally concentrated in the line peaks, especially of strong absorption lines, etc., and increases with increasing opacity. Net radiant cooling per unit mass, OTOH, tends to peak in magnitude** at intermediate opacities …
(except at temperature discontinuities over optical depth – eg. TOA (net cooling per unit mass is unbounded) – also at discontinuities in slope of Bν over *****normalized optical depth (net cooling per unit mass approaches a nonzero saturation limit))
…, where there is a significant amount of absorption cross-sectional area per unit total mass, but a significant distance over which photons may travel from emission to absorption – ie., the hotter and colder cross sections can still ‘see each other’ and so there can be net fluxes from hotter to warmer masses.
(**- Net radiant cooling may flip sign (and net fluxes through any horizontal area may flip direction), over the course of doublings of opacity, depending on the shape of the temperature profile (in terms of Bν(normalized optical depth as vertical coordinate)), but in the extreme-end values (transparency, quintuple²⁰ pea soup fog), net radiant cooling or warming …
(between and excepting any bounding ‘surfaces’ ie., Space, surface, clouds’ ‘surfaces’ if you count them separately, etc.)
… goes to 0 (with exceptions noted above).)
*****Normalized optical depth (as vertical coordinate) = height in terms of τ (as vertical coordinate), ÷ total τ of whole column of atmosphere. Uniformly doubling τ (optical depth), ie., doubling k_a (which may vary as a function of vertical mass path), keeps normalized optical depth constant.
Column total Gross radiant cooling (for isotropic absorption) (excluding stimulated emission), per unit horizontal area, = ∫ ∫ 4π sr · Bν dτ · dν
——- ——– ——–
It may seem confusing because many people are accustomed to thinking about fluxes through areas, eg., upward, downward, and net vertical fluxes at various heights.
B.E. Finch: “ Obviously, the TOTAL photons manufactured would only be of similar quantity to the leakage if the IR gases absorbed hardly any photons, which I don’t think is the case.” – perfectly correct, ie., in the limit of zero optical thickness, all absorption cross-sectional area is visible (not hidden by other cross sections) so all the glow emitted escapes the volume.
patrick o twentyseven says
Correction: … the absorption cross section σ_a is the area which would absorb the intensity (= radiance * area facing a direction) that a unit of material net-absorbs. …
patrick o twentyseven says
Clarifications1:
The dependence of blackbody spectral radiance (Bν) on (n_{r,refraction})² is for n_{r,refraction} of the material/space through which the radiance is going. Eg., imaging a glass sphere with n_{r,refraction} = 2 (a bit unrealistic, perhaps, but I want a nice round number), with a perfect antireflection coating; using approx. that n_{r,refraction} = 1 outside it. Embedded concentrically within is a perfect blackbody spherical surface BSS (if necessary, assume its material has n_{r,refraction} ≥ 2). Within the glass, the radiance coming from the BSS is 2² Bν(1) = 4 Bν(1) where Bν(1) is Bν for n_{r,refraction} = 1; BSS looks just as big as it is; let it have radius r_{BSS}. From outside the glass, the radiance coming from BSS is Bν(1); (***I haven’t verified this with computation of the critical angle for Total Internal Refraction (TIR) but I expect that:) if the glass sphere r ≥ 2 r_{BSS} (assuming this avoids TIR of rays from BSS) BSS should appear to have twice the radius and thus 4 times the area that it actually does; the total flux emitted from BSS escapes the glass. If the glass is smaller than there must be TIR for some of the rays coming from BSS; people living on BSS would see a superior mirage.
patrick o twentyseven says
“Total Internal Refraction (TIR) ” – oops – TIR = Total Internal Reflection : https://en.wikipedia.org/wiki/Total_internal_reflection
“I haven’t verified this with computation of the critical angle for Total Internal Refraction (TIR) but I expect that:”…:
Good News – it works! Two right trianges BOG and B’OG, sharing the hypotenuse OG (O = center of spheres; G = point on glass sphere (GS) where ray emitted from B crosses surface); legs BO = r_{BSS} and B’O = r’, and legs from G to a points B (following emitted ray) and B’ (projecting back in direction of refracted ray to where visible edge of BSS would appear from outside GS):
n_{₂,ref} ÷ n_{₁,ref}
= sin(θ₁) ÷ sin(θ₂)
= (B’O / OG) ÷ (BO / OG)
≡ (r’ / OG) ÷ (r_{BSS} / OG)
= r’ ÷ r_{BSS}
https://en.wikipedia.org/wiki/Snell%27s_law
https://en.wikipedia.org/wiki/Snell%27s_window
Note: the visible edge of BSS, as would appear from outside GS, is a bit around the backside (from an infinite distance, you would see more than half of BSS at a time); each unit area on BSS is not (generally?) magnified by (n_{r,ref})², but is visible from a wider range of directions.
Note: change in radiance during refraction doesn’t require a curved surface; so long as geometric optics applies (AFAIK), it only depends on n_{ref} – the relation is easily (well, ~) derived for a flat interface, which locally approximates any smooth surface. Thus there is a fundamental difference between magnification of objects behind a lens and of obects within a lens.
Thus, the dependence of blackbody radiance on (n_{r,ref})² is necessary for refraction to not violate the 2nd Law of Thermo. But the only place I’ve seen this dependence on (n_{r,ref})² explicitly stated was in the book “The Physics of Solar Cells” by Jenny A. Nelson:
https://www.google.com/books/edition/The_Physics_Of_Solar_Cells/4Ok7DQAAQBAJ?hl=en&gbpv=1&dq=inauthor:%22Jenny+A+Nelson%22&printsec=frontcover (and it’s no longer in the previewable portion). PS TIR can be used to improve solar cells.
patrick o twentyseven says
Clarifications2:
https://en.wikipedia.org/wiki/Opacity
…
The above @ https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823793 assumes all atmospheric optical depth is from absorption. Elastic scattering, which (approximately*) conserves photon energy, cannot directly add to emission or absorption but can redirect where absorption occurs (*I presume small changes in energy would be an additional line-broadenning mechanism(?)). Elastic scattering is negligible for LW radiation within the atmosphere AFAIK, though there is some such scattering and reflection at the surface; these are more important for SW photons; although a greenhouse effect could hypothetically be based on scattering. Inelastic scattering … https://en.wikipedia.org/wiki/Inelastic_scattering#Photons (?) AFAIK/AIUI not energetically significant for Earth’s climate, but is important in stars AIUI.
https://en.wiktionary.org/wiki/AIUI
Another way to look at fluxes:
The fluxes through an area at a location are composed of contributions from the fluxes, from point of emission to point of absorption, between pairs of volumes. For each such pair, if each volume is sufficiently small as to be approximated as isothermal, yet large enough for the population of molecules/etc. to be statistically significant (– and at LTE/LEDNLIE), the net flux is from higher to lower T (at least if ΔT is larger than sum of approximation errors), but the sizes of the contributions from different pairs vary with changing opacity, so the net flux at a given location can change direction.
(Also, with scattering or reflection, a larger/more area(s) w/could be needed to completely catch the total flux from one volume to another.)
https://en.wikipedia.org/wiki/Radiance#SI_radiometry_units :
Φ (radiant) flux: rate of energy flow, ie. power
flux density: flux per unit area (through an area)
I intensity: flux per unit solid angle, in a direction
(note the word “intensity” is often used for other things, though)
L radiance: flux density per unit solid angle, in a direction, through an area facing that direction. If you focus at ∞ (infinite distance), then, with some caveats***, radiance corresponds to the brightness you see at a point in your visual field.
spectral ___ – amount of ___ per unit of the spectrum (at a given point in the spectrum). (PS I often leave out the word “spectral”, relying on context.)
…
( https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823885 – …“ the relation is easily (well, ~) derived for a flat interface,”… based on Snell’s Law;
https://en.wikipedia.org/wiki/Radiance#Conservation_of_basic_radiance )
Barry E Finch says
I forgot to mention that its specific purpose (apart from I think the general description is a logical way) is to (correctly) de-couple by IRRELEVANCE memes regarding the split of surface energies into air into sensible, water-latent, LWR from the actual reality by correctly coupling sensible, water-latent & LWR and attack Junk memes of the variety “(gunf)2nd Law of Thermodyamics(gunf)”, “the surface heats itself”, “the big atmospheric circulation is thermals not LWR which is a minor player!” with a minor local aside (far lesser junky than the preceeding) of our JCM’s discussions of its gut feelings about upwelling, downwelling surface LWR amounts, the complex crinellations and rich Corinthian leather of the turbulent surface layer, and some (not all) aspects of evaporation latent heat. I realized in July 2018 when I took a longer look on the couch (almost an hour I think) at “greenhouse effect” than in 2016 and realized that the nonsense “LWR up from surface gets re-emitted, s0 50% goes back into surface” was an utter boon to Koch Industries, which I’ve definitely seen proved the last 12 years in absurd disinformational videos, and I quick tried a trial balloon to discuss on Realclimate about that nonsense in July 2021 or July 2022 (or in some month of some year) but it got Boreholed,
Barry E Finch says
Some hyper-advanced mathematics from me to boast my hyper math skills & hyper science skills simultaneously, all novel thought and nothing stolen:
* A 7-year doubling scenario curve exceeds 1 m around 2055 and 2 m around 2061;
* A 10-year doubling scenario curve exceeds 1 m around 2063 and 2 m around 2072;
* A 13-year doubling scenario curve exceeds 1 m around 2070.
* A any-year doubling scenario is totally meaningless because it contains no ice sheet dynamics whatsoever and the ice must get itself below sea level in order to raise sea level.
I’m just plain showing off hyper-advanced mathematics & science
Geoff Miell says
Barry E Finch: – “A any-year doubling scenario is totally meaningless because it contains no ice sheet dynamics whatsoever and the ice must get itself below sea level in order to raise sea level.”
In the YouTube video titled Ep. 2 | Why is Greenland melting so fast? Ft. @JasonBoxClimate, published 15 Jun 2023, duration 0:09:16, included the following discussion:
06:34 Dr Ella Gilbert: And can we say what we’re already committed to from Greenland?
06:38 Prof Jason Box: Right, we studied the ice loss commitment from Greenland, and the variations from year to year, they actually point squarely at an ice loss commitment that right now stands at at least 27 centimetres of global sea level rise, but that’s if the climate stayed constant up to 2019. Climate will continue warming and so the ice loss commitment grows. In a high emissions scenario, Greenland’s ice loss commitment reaches more than one metre by end of century. So we have some time to get off of that high emissions scenario and basically halve the, the sea level commitment from Greenland to about half a metre by end of century.
07:31 Dr Ella Gilbert: So what would a lower melt, or perhaps more optimistic future path for this century look like in Greenland and how would that differ from a more pessimistic view?
07:44 Prof Jason Box: Say, like the difference between something close to the Paris climate agreement scenario and the high emissions scenario, is about a factor of two for Greenland’s sea level contribution. So there’s a lot of value in finding ways to reduce carbon emissions and get into carbon dioxide removal.
08:08 Dr Ella Gilbert: So, there’s the answer: the biggest loser in the Greenland melt story is surface melt, and a lot of it happens when weather patterns conspire to bring much warmer air up from the south a drive extreme melting events. On the surface of it, that doesn’t sound great, especially given that our atmosphere is heating up extremely rapidly and we’re seeing more and more of those extreme events. However, because temperatures in the atmosphere can change much faster than in the ocean, in some ways it’s a bit of a silver lining because it means that melting can slow down pretty quickly too once we reduce emissions and turn down that dial on the climate heating. Shifting into that lower emissions world that Jason spoke about is still possible and even though it still means some degree of further sea level rise, it’s far preferable to the alternative. But something we REALLY need to steer clear of if we’re going to minimise ice losses from Greenland is tipping points, which – funnily enough – is the subject of our next video.
https://www.youtube.com/watch?v=tRtqOTtsCr8
The discussion above is just talking about Greenland’s contributions to SLR:
* circa 0.5 m by 2100 for holding at or below +2.0 °C global warming level;
* circa 1.0 m by 2100 for +4.0 °C global warming level.
I’d suggest you watch the YouTube 5-part series Biggest Loser with Dr Ella Gilbert and Professor Jason Box.
https://www.youtube.com/playlist?list=PL5goLFawFwF0V2l_uW3I_lho8E4WJLCoy
Add in the Antarctic’s contributions to SLR and ocean thermal expansion and I’d suggest more than a metre of SLR is inevitable by 2100, unless we/humanity find some way to cool down the planet fast.
The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.
“The greatest shortcoming of the human race is our inability to understand the exponential function.” – Albert Allen Bartlett
https://en.wikipedia.org/wiki/Albert_Allen_Bartlett
Nigelj says
Geoff Miell:
“The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.”
Yes to get above 1 metre SLR this century, and certainly to get above 2 metres, looks like it would indeed need exponential growth of SLR. Exponential growth wont happen at scenarios of 2 – 5 degrees C of warming and from thermal expansion of the oceans, and melting of glaciers from the top down, and current ice sheet dynamics.This is generating a quadratic growth curve over this century. Im not an expert by a long way, but all that is fairly obvious maths and physics.
We have seen short periods of exponential growth in Greenlands surface melting but this even if it continues, looks insufficient to lead to exponential growth in global SLR. MAR posted some histortical numbers on all that. Although its still adding to SLR and the cumulative effects do add up ominously.
To get to exponential SLR and multi metre SLR this century requires a change in ICE SHEET DYNAMICS. A disintegration of the ice sheets in Antarctica and Greenland. My recollection is that James Hansens findings are that above 2 degrees you kind of reach a tipping point where glaciers start to dramatically speed up their flow into the oceans and the face of glaciers start collapsing at a very enhanced rate. This in turn relates to how glaciers are grounded. This process is exponential for a limited period until it stabilises, but hence you get exponential SLR this century and possibly into next century. I think hes very credible on this mechanism in principle. He calculated that 5M SLR is possible this century.
The paleo record has periods of multi metre SLR per century, like meltwater pulse 1a where you had 4M per century, starting rather abruptly and ending quite abruptly after about 5 centuries, and then reverting back to about 0.5M per century for a long time. This abruptness suggests a change in ice sheet dynamics. However there was also more ice sheets back then to melt so its hard to know how much ice sheet dynamics contributed but clearly it was significant because nothing else would easily explain the abruptness of the change.
Its hard to be sure what will happen this century and whether SLR would be as much as 5M, because of knowledge gaps around exactly how glaciers will behave. We know a change in dynamics is very likely but its hard to quantify the rate of change precisely. But I believe we know enough to know rapid multi metre SLR is very possible and only a fool would completely dismiss Hansen.
I think we are heading to 2M SLR this century, all things considered, and if we dont cut emiisions to zero by 2050. But To me quibbling over whether we have 1, 2, or even 5 metres SLR this century may not be the main point. Because anything above 1 metre looks very serious and ;possible, so thats enough to get me worried and reason enough to take action. We simply cannot afford to play Russian Roulette and hope we can do nothing and dodge a bullet because the consequences of rapid multi metre SLR are too large. Just my two cents worth.
Sabine says
to Nigelj
you say – “He calculated that 5M SLR is possible this century.”
Did he? Can you remember where? Because my memory, and I could be wrong, was in the Ice Melt paper he said 5m slr per century was the fastest rate from historical paleo evidence.
Not that 5m by 2100 was possible or likely. Of course it’s all academic and not that important either way. No one of note seems to be taking his work seriously anymore. Unfortunately.
nigelj says
Sabine you ask where Hansen calculated SLR could be 5M this century. I just cant recall exactly and a quick google didnt help find it. It was about ten years ago at least and I think it was media commentary on one of Hansens studies, or maybe it was on some BOE calculations.
But I found this commentary from 2016 fyi. Its not what I read, and it seems more recent, but its saying 5M of SLR may happen over a period of 50 years and hes tallking about this potentially happening in our future:
“All Eyes on the Oceans: James Hansen and Sea Level Rise”
By Sasha Wright
“On July 23,(appears to be 2016) James Hansen and 16 co-authors posted a discussion paper on an open-review website about sea level rise and climate change. The article has garnered massive attention around the internet and scientific communities — both for its content and for the unconventional manner in which it waspublished. The authors bring special attention to a particular aspect of global climate change that often isn’t discussed. Namely, global sea level rise. While many of us discuss the catastrophic impacts of droughts, flooding, and dwindling food supply related to climate change, the authors emphasize that up to 5 meters of sea level rise may happen over the course of 50 years, carrying with it the “economic and social cost of losing functionally all coastal cities…” Seeing as the more conservative IPCC report puts this estimate closer to 1 meter by the year 2100, this news is making an impact. ”
(the article then goes onto discuss the SLR mechanism)
https://theplosblog.plos.org/2016/03/repost-james-hansen-and-sea-level-rise-the-peer-reviewed-version/?__cf_chl_tk=6VcrMY1QSfEZ3NNGM9eXA.oG8HCYWT41JsdJds5PlV8-1723942713-0.0.1.1-5012
The commentary appears to be based on The paper ” Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2◦C global warming is highly dangerous, Hansen and others, 2015″
https://acp.copernicus.org/preprints/15/20059/2015/acpd-15-20059-2015.pdf
I just take a general interest in climate change. I just wanted to make the point that the IPCC SLR projection of 1M SLR this century is based on a gradual melting process and follows a quadratic curve, and to get to multi metre SLR as high as 5M within this century, would require some sort of step change process involving ice sheet dymanics, and my recollection is Hansen said it would involve exponential growth. Although as John Pollack points out other curves could also get to multi metre SLR. It intuitively looks to me like it would be quite a steep curve and a fairly abrupt departure from the trend of the last couple of decades.
Geoff Miell says
Nigelj: – “I think we are heading to 2M SLR this century, all things considered, and if we dont cut emiisions to zero by 2050.”
I’d suggest it requires more than just cutting GHG emissions to zero well before 2050. It also requires atmospheric carbon drawdown, and maintaining Arctic sea ice cover.
I’d suggest breaching the +1.5 °C global warming threshold is inevitable, and likely sometime around 2030, maybe as early as 2028, maybe as late as 2036.
https://www.carbonbrief.org/analysis-what-record-global-heat-means-for-breaching-the-1-5c-warming-limit/
It seems +1.6 °C global warming threshold is the best estimate for the tipping point for the Greenland ice sheet. The longer the Earth System stays at or above this threshold the more difficult it would be to avoid the collapse of the Greenland ice sheet. I’d suggest the Earth System will likely be in that territory sometime in the 2030s.
https://www.sciencedaily.com/releases/2012/03/120312003232.htm
I’d suggest lethal humid heat and worsening global food security are likely to manifest well within the remainder of the first half of this century as the Earth System continues to warm further, progressively worsening the lives of tens to hundreds of millions to perhaps billions of people, well before SLR likely gets to & above the 1 m level sometime in the second half of this century.
https://www.nature.com/articles/s41893-023-01132-6
https://x.com/rahmstorf/status/1661450321766371329
Without atmospheric carbon drawdown SLR is already committed to 20+ m.
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823597
Piotr says
Nigel: The paleo record has periods of multi metre SLR per century, like meltwater pulse 1a where you had 4M per century, starting rather abruptly and ending quite abruptly after about 5 centuries
Nigel, I don’t think this is a good analogy. The “multimeter” meltwater pulses you speak of didn’t come from currently melting ice, but from breaking of the ice dams, letting the meltwater accumulated there during the previous centuries in giant lakes at the edge of the N. American ice sheet. There are no giant lakes that have accumulated the meltwater over many centuries on Greenland or Antarctica. And in the context of the current discussion – those meltwater SLR pulses do not seem to be exponential over their duration of the pulse.
Similarly, the abrupt end of them may not be instructive for near future either
1. the rate of the meltwater supplied to N.Atlantic then – was MUCH higher than today – which may be the difference between shutting down the AMOC, resulting in a period of flat SL then, and possibly only weakening of AMOC now.
2. And even if we have massive melting now – it would be from Antarctica – shutting down local downwelling around Antarctica, which is only a minor contribution comparing to the AMOC downwelling in the N. Atlantic – i.e. the location next to the source of N. American ice sheet during the past meltwater pulses.
To sum up – the mechanism and therefore the RATE of the future SLR almost certainly will be different than those during the meltwater pulses during the deglaciation.
Nigelj says
Piotr.
You’re right that meltwater pulse 1a (with 4m SLR per century) is not a great anaology for our situation, but I think we can still learn something from it. The wikipedia article on meltwater pulse 1A says there is still uncertainty about whether the principal cause is 1) the laurentide ice sheet and the related mississippi river flood events (ice dams breaking) or 2) the antarctic ice sheet melting or 3) the Fennoscandian and Barents Sea Ice Sheets.
The commentary did mention that theres evidence Antarctica contributed 2M per century due to rapid local warming. This is the reason I said I think 2M SLR per century is a more realistic worse case scenario for our times. Its also a reason to believe a 1 metre prediction of SLR by 2100 is too conservative.
Piotr says
Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today,
and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.
With two past forcings absent today, and the third likely very different – any extrapolation of the past rates of SLR on the today or future ones – is _extremely_ questionable, if not outright misleading – promising insight from the past where, due to the differences with today, there is none.
Mal Adapted says
Tangentially, I enthusiastically recommend the 1992 book by the late E.C. Pielou titled After the Ice Age: The Return of Life to Glaciated North America. The author, a Canadian statistical ecologist, devoted chapters to what was then known about the hydrology and ecosystems of those giant periglacial lakes, up to their catastrophic drainages. The whole book is fascinating, a masterpiece of historical ecology. The woman held a vast store of facts in her brain, and connected them all together into a powerfully explanatory, broadscale narrative. Events may not have proceeded exactly the way she envisioned, but the story is irresistible to anyone who’s ever wondered about how that recent episode of natural climate change played out on the landscape.
John Pollack says
GM: The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic.
Geoff, I’m puzzled as to why you insist on framing SLR in terms of an exponential function. The math is simple, but wrong and misleading. The quote above illustrates part of the problem. Having to choose an AVERAGE doubling time implies that you aren’t really talking about a rise described by a single exponential function. There is a single exponential function with a real, positive exponent that will produce a rise of 1m at 2100. If we were actually on that curve, there would be a particular doubling time, and no need to seek an average.
What we are all really talking about is some sort of SLR that starts out small with the observed values, but comes to increase rapidly before 2100. (Even the 2100 date is arbitrary, because the process will continue for centuries or millennia beyond 2100.) There are an infinity of polynomial functions that will produce this behavior in one way or another. Statistically, starting with a small rise and additional noise means that you wouldn’t be able to pick one over another from the observed data.
On another level, even having a single function to describe SLR is misleading, because the rise depends on both future human behavior for emissions and mitigation, as well as ice dynamics. Any function we pick to fit the available curve will lack predictive skill. In fact, any will be false if extended long enough, so you also need a way to determine when the curve will cease being applicable.
I strongly agree with the overall concern that we and the planet are in big trouble with sea level rise, and setting up for a very rapid rise. This is based on solid evidence from the last interglacial. Sea levels ended up shockingly higher than present values, and at least part of the rise was rapid – starting at levels already about 2m higher than present values. This occurred with CO2 levels no more than 300 ppm, but with a higher obliquity of axial tilt than present values, The higher obliquity resulted in relatively more solar energy incoming in the polar regions, and less in the tropics, than at present. Perhaps this is why we are already seeing coral deaths due to warm tropical oceans, while the ice sheets are just beginning to melt rapidly. In addition, both the meteorology and ocean currents will be at least somewhat different with hotter tropics and cooler poles than last time around, about 120,000 years ago.
Geoff Miell says
John Pollack: – “Geoff, I’m puzzled as to why you insist on framing SLR in terms of an exponential function.”
Per the Hansen et al. (2023) paper titled Global warming in the pipeline (bold text my emphasis):
https://doi.org/10.1093/oxfclm/kgad008
John Pollack: – “The math is simple, but wrong and misleading. The quote above illustrates part of the problem. Having to choose an AVERAGE doubling time implies that you aren’t really talking about a rise described by a single exponential function.”
I stated on 8 Aug 2024 at 10:12 PM:
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823627
Please read what I’ve previously stated. That way, there’s perhaps less chance of misunderstanding.
I’d suggest the rate of SLR acceleration will likely to be a composite of multiple doubling times over the coming decades while the energy inputs into the Earth System, and more particularly into the cryosphere and oceans, increase. Various tipping points with the Greenland and Antarctic ice sheets are also likely to vary the doubling times.
The UN Sustainable Development Solutions Network (SDSN) published on 3 Nov 2023 the YouTube video titled An Intimate Conversation with Leading Climate Scientists To Discuss New Research on Global Warming, duration 1:12:23. From time interval 0:17:03, James Hansen said:
“The 1.5 degree limit is deader than a doornail, and the 2 degree limit can be rescued only with the help of purposeful actions to effect Earth’s Energy Balance. We will need to cool off Earth to save our coastlines, coastal cities worldwide, and lowlands, while also addressing the other problems caused by global warming.”
From time interval 1:04:03, James Hansen on tipping points said (bold text my emphasis):
“Yeah, the most important tipping point is the, the Antarctic ice sheet, and in particular the Thwaites ah, Glacier, which who’s grounding line has been moving inland at a rate of about a kilometre per year, and ha, in another 20 years, it will reach a point where it, it… the, the um, bed ah, is so-called ah, retrograde bed, so it gets deeper. The Antarctic ice sheet sits on bedrock below sea level, but it gets deeper as you go towards the centre of the continent, and it gets… It hits a canyon in about 20-years if we continue at one kilometre ah, per year. When it hits that canyon you’re going to get very rapid disintegration of that glacier, which is basically the cork that’s holding ah, a lot of the West Antarctic ice ah, in the bottle. So we don’t want to get there. And if we want to prevent, to slow down, and even stop the melting of the Antarctic ice sheet we have to cool off the planet. That’s, um… And, and we need to do that because, hah, more than half the large global cities in the world are on coastlines, and there are a lot of lowlands. Ah, so, that, that’s the tipping point which ah, I think dominates. But it so happens that there’s so many other ah, climate impacts that we would be getting to see and it would be much more if we go beyond two degrees, that there are many reasons to want to cool off the planet. If we want to keep a planet that looks more or less like the one that has existed the last ten thousand years, we actually have to cool off the planet back to a Holocene-level temperature, and that’s possible, but it’s not easy.”
https://www.youtube.com/watch?v=NXDWpBlPCY8
Adapting to climate change won’t be possible in many locations on planet Earth, on our current GHG emissions trajectory.
https://www.nature.com/articles/s41893-023-01132-6
For the indicative GMST anomalies, the purple coloured areas shown in the gif animation are regions where the mean annual temperature (MAT) is projected to be above 29 °C, which is considered to be no longer habitable for humans (or at least that’s the situation without effective air conditioning).
https://x.com/rahmstorf/status/1661450321766371329
Piotr says
Geoff Miell, quoting Hansen: “ Concern was based on observed ice sheet changes and paleoclimate evidence of sea level rise by several meters in a century, implying that ice sheet collapse is an exponential process ”
The problem is with that “ implying
An extremely complicated phenomenon like sea level rise is NOT LIKELY to be described adequately by a simplistic mathematical formulation ( a straightforward exponential function, i.e. with a fixed exponent).
Further – as pointed out by John Pollack and then me – the pattern and mechanisms of the past rapid SLRs during deglaciations – are very different than those today – hence one can’t extrapolate past situations and the coefficients of the exponential function from the past data, onto the current ones.
Which confines us to the recent data (the last decades) – yet the very nature of the predictions based on the exponential models is that they are hugely sensitive to even small errors in the calculation of the exponential function coefficients from the early data.
Geoff Miell says
Piotr (at 19 Aug 2024 at 9:02 AM): – “An extremely complicated phenomenon like sea level rise is NOT LIKELY to be described adequately by a simplistic mathematical formulation ( a straightforward exponential function, i.e. with a fixed exponent).”
It seems to me you have demonstrated selective blindness again.
Repeating my earlier comments again:
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823806
And also this:
It seems to me you persistently demonstrate a habit of ignoring (and/or denigrating) comments that are inconvenient for your narratives.
What is known:
* The long-term rate of sea-level rise has more than doubled since the start of the satellite record, increasing from 2.13 mm/y between 1993 and 2002 to 4.77 mm/y between 2014 and 2023.
* Acceleration: 0.12 ± 0.05 mm/yr²
* The rate of SLR is currently around 5 mm/year.
Figure 6 in the WMO’s State of the Global Climate 2023.
Arguably one of the foremost experts on Greenland ice sheets and glaciology, Prof Jason Box, suggests for global mean SLR levels:
“My best guess, if I had to put out numbers; so by 2050, 40 centimetres above 2000 levels…”
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823661
I think it would be foolish to ignore/dismiss the warnings from multiple credible sources that SLR is accelerating and will be relentless for centuries to come, unless we/humanity take steps and begin to cool planet Earth back to Holocene levels within the next few decades.
Piotr (at 19 Aug 2024 at 9:02 AM): – “Which confines us to the recent data (the last decades)”
Nope. It also includes all available data including the paleo-historical record. What has happen in the past should inform future possible outcomes. As Professor Schellnhuber put it in response to a question by Jørgen Randers after Schellnhuber’s 2018 Aurelio Peccei Lecture: “…simply because this is our reality lab, ja?”
https://youtu.be/QK2XLeGmHtE?t=2781
It seems to me you (among some others here at this blog) are cherry-picking some data to support your ideological narrative and ignoring/denigrating other data that’s inconvenient.
John Pollack says
Okay, I believe I get it now, Geoff. There’s a precise mathematical/scientific definition of an exponentially rising curve. Then, there’s a much looser colloquial concept of an “exponential rise” with a doubling time that may or may not be consistent or relevant, and which may or may not contain tipping points, etc. You prefer the colloquial usage to inform us in this scientific blog. If we find it imprecise or confusing, we can just read all about your intended meaning.
I feel rather like when I go to a store to pick up a particular item. However, I don’t find it in the accustomed section. I can look all over the store for it, and probably find it still. Perhaps the prolonged search was the intended purpose of moving it around. Or, it may not be there at all. I will keep the experience in mind when deciding whether to visit the store in the future.
So be it.
Piotr says
Geoff Miell: It seems to me you have demonstrated selective blindness again. Repeating my earlier comments again: “Real-world ice melt will not follow a smooth curve”.
How to eat cake and lecture others on being “selectively blind” for seeing you … chomping down the cake…
Geoff Miell, eating the cake – quoting Hansen:
“ Concern was based on observed ice sheet changes and paleoclimate evidence of sea level rise by several meters in a century, implying that ice sheet collapse is an exponential process ”
“Exponential” means f(t)= f(o)*e^(rt). As such, it has a SINGLE doubling time. To quote Geoff Miell lecturing others: “That’s simple mathematics and logic”
The exponential formulation may be a useful where there is only a single process dominating – such as an exponential growth of population, or exponential decay of radioisotopes. Where there are many important interactions – exponential formulation is useless, or outright – misleading – promising insight, where there is none, and resulting in INFLATION of a given process over time – the exponential function for r>0 it produces MASSIVE increases over time – hence it is a function of choice for those who are invested in as large SLR as possible, for instance:
==== Geoff Miell :
For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024:
2040: 156.7 mm (or 244.1 mm SLR relative to the Jan 2000 level)
2050: 383.0 mm (or 470.4 mm SLR relative to the Jan 2000 level)
2060: 835.7 mm (or 923.1 mm SLR relative to the Jan 2000 level)
2070: 1741.0 mm (or 1828.4 mm SLR relative to the Jan 2000 level)
By 2100, voila – 14 metres!
=====
And no – you don’t account for the multiple complicated interactions determining real-world SLR by simply … repeating the same exponential calculation, but a with a slightly different coef. r, as in:
Geoff Miell :
For a 10-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024: ….
For a 13-year doubling scenario, with a 5 mm/y SLR rate at the beginning of year-2024: ….
All you have done – was to calculate two separate scenarios for two slightly different values of r. Doing so does NOT mean that you used “ a composite of multiple doubling times.
In fact have you used VARIABLE r – it would not longer be “exponential process” (Hansen).
So, in the light of the above – who of us two has “demonstrated selective blindness again, Mr. Miell ?
Nigelj says
Piotr. I normally like your clear, persuasive comments, but your post replying to GM is a bit hard to follow. For example Hansen did mention he thought the past collapse of the Antarctic ice sheets was an exponential process. Im assuming you accept this but are arguing that it would not cause exponential SLR because of all the other factors contributing to SLR. Which sounds correct. Hope I have that right. It would however obviously cause an acceleration in SLR .
The exponential process might have been due to how glaciers move towards the oceans and potentially speed up. Some geological processes do have exponential growth for example how landslides develop as below. So its not confined to things like population growth or financial processes (not that you said that). So Hansen could be right. Refer:
https://www.nzgs.org/libraries/understanding-patterns-of-movement-of-slow-landslides/
You previously talked about melwater pulse 1a (causing 4M SLR per century) and mentioned circumstances were different back then so we cant assume we will get 4M or more SLR in our futures and I accept youre right overall. There was far more ice back then for a start.
However you also mentioned MWP 1a was caused by ice dams breaking. Please note that the Wikipedia entry on meltwater pulse 1a (4M SLR per century) says there is still controversy over the main cause. The commentary says it could be ice dams breaking related to the laurentide ice sheet, or the Antarctic ice sheet disintegrating or other ice sheets disintegrating.
The commentary also said that there is evidence the Antarctic caused 2M of SLR per century back then. I think this is an important point buried in the commentary. It might be the thing we should pay a lot of attention to. It suggests we could have 2M SLR per century, perhaps this century, especially when you factor in ice loss from other regions and causes. I’m a bit sceptical of claims we could have 4-5 M SLR this century.
Piotr says
Re Nigel Aug 22:
As for your other question, on the meltwater pulse 1a – I answered it in the post to you
send on the same day (Aug 22) (that’s probably why you didn’t see it).
So here it is again:
====
“Piotr Aug 22:
Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today, and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.
With two past forcings absent today, and the third likely very different – any extrapolation of the past rates of SLR on the today or future ones – is _extremely_ questionable, if not outright misleading – promising insight from the past where, due to the differences with today, there is none.
=====
Nigelj says
Piotr
“Re Nigel Aug 19. Of your 3 possible factors – the first two- mass of water stored blocked by the Laurentide ice sheet and the Fennoscandian and Barents Sea Ice Sheets, DO NOT EXIST today, and there is no reason to assume that Antarctica ice sheet at the beginning of deglaciation is very similar to the one today., when presumably all the part of the ice sheet easy to melt are long gone.”
I agree that we dont have the huge laurentide, fennoscandian and Barrents sea ice sheets today. I do actually realise conditions were generally different back then, which is why I never suggested in any comments we would be seriously likely get 4M SLR / century like meltwater pulse 1a, and that it would more likely be something like 2M.
However you are presuming all or part of the Antarctic ice sheet easy to melt are long gone. Im not sure what is meant by easy to melt. We can be reasonably sure the ice sheets and glaciers were more extensive but Its not clear why that would make them easier to melt.
All I’m saying is it appears that MWP1a had a rapid onset and multimetre SLR per century of 4M and that it looks like the Antractic may have contributed about 2M of this SLR. Something triggered that rapid Antarctic melting process and its been suggested it was warming Antarctic oceans and speeding up of glaciers moving towards those oceans. Such conditions look like they exist today and increasingly so in our futures if we dont cut emissions. Plenty of studies on all that. We cant be sure it would generate exactly 2M SLR, but for me its a WARNING that we may be on the verge of triggering rapid and substantial SLR.
Piotr says
Nigel Aug.27: “You are presuming all or part of the Antarctic ice sheet easy to melt are long gone. Im not sure what is meant by easy to melt.
Those which at the edges – iceshelves and glaciers along the shore – that are most exposed to the outside changes, particularly ocean water – they are last to grow during the glaciation and first to melt during the deglaciation stage.
Thus in the late stage of natural deglaciations (as we would have been if not for our HGH emissions) – there is not much left to be easily melting – melting kms-thick ice cap on land (i.e. not exposed to the ocean waters which melt ice much easier than air) and having 100s of 1000s of km to go horizontally before being able to add to the SLR by calving – won’t be as easy/quick.
NIgel: “ Something triggered that rapid Antarctic melting process and its been suggested it was warming Antarctic oceans and speeding up of glaciers moving towards those oceans. Such conditions look like they exist today and increasingly so in our futures if we dont cut emissions.
Nigel, my point is that the conditions TODAY are nothing like those in the early stages of deglaciation (14ky ): since today you don’t huge amount of easily=quickly meltable ice the way you had early in deglaciation 14ky => you should not expect anything comparable in term SLR RATES.
See also my 24 Aug 2024 at 7:31 PM post (near the end of this monthly thread) –
“Still warm ( 21 Aug 2024): “The West Antarctic Ice Sheet may not be vulnerable to marine ice cliff instability during the 21st century ‘ Morlighem et al.”
Past is a good predictor of the future only if the future conditions/patterns are like those in the past.
Tomáš Kalisz says
In re to Piotr, 28 AUG 2024 AT 2:49 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824087
Dear Piotr,
Again, I appreciate your explanations of the differences between present situation and situation before meltwater impulses. I think that all arguments you brought against the threat of a quick multi-metre SLR during 21st century sound reasonably and are quite persuasive.
In case that you could be willing to cease your fire and seriously deal with a question from a sentenced denialist like me, I have one, regarding the longer-term perspective of the Antarctic ice sheet.
On one hand, there are concerns (please correct me, if I am wrong) that already the present atmospheric concentrations of GHGs can – provided that they should persist for thousands of years – may cause a global temperature increase substantially exceeding 2K against preindustrial level. It seems obvious that such a warming may cause substantial thawing of the Antarctic ice sheet, and it seems even more obvious that the thawing should be even stronger if the present GHG forcing further increases.
On the other hand, it was mentioned several times in discussions herein on RC that (at least during polar winter), the GHG effect in fact cools Antarctica. If so, I would like to ask if this fact may suggest that thawing of the majority of the Antarctic ice sheet – whereby I mean the part which is not in direct contact with ocean – may not be a such straightforward consequence of the increased greenhouse effect as it might have looked on the first sight?
Are there already detailed studies that assess how various mechanisms contributing to ice deposition and/or thawing in Antarctica may change as a result of the increased greenhouse effect itself and of its feedbacks like global ocean warming and possible changes in ocean streams?
Greetings
Tomáš
Piotr says
re: John Pollack Aug. 17
Great points, John, both on problems with using an exponential function to describe future SLR, and on the difference between the current melting and the one in the last interglacial – the latter triggered by orbital warming of the Arctic (in summer), the current one seeing much more “diffused” warming from surplus CO2. In addition:
– there was also much more “disposable” ice then (worth of 135m SLR), only < half of that left now in Greenland and Antarctica
– as I already indicated to Nigel – SLR may be modified by shutting down the downwelling in N. Atlantic that drives AMOC. You CAN do it when most of the meltwater comes from N. America (then), not when most of it is to come from Antarctica
– the past deglaciations started with much more of sea ice in N. high lats than we have today – hence the ice albedo -T feedback in the past have much more seaice-area to work with than it has today.
One can't walk into the same river (here: the same SLR mechanisms, ice patterns, and thus SLR rates) twice.
John Pollack says
Piotr, I agree that the situation is different from the last interglacial (LIG), for the reasons you highlighted and others – especially the difference in GHG levels and causes.
For clarity, I was referring to the warm period after the LIG had already begun. My thinking is heavily influenced by : O’Leary, M., Hearty, P., Thompson, W. et al. Ice sheet collapse following a prolonged period of stable sea level during the last interglacial. Nature Geosci 6, 796–800 (2013). https://doi.org/10.1038/ngeo1890
The title of the paper and the abstract provide a decent summary. After a period of interglacial warmth, in which the SL was fairly stable – already about 3m higher than current values – there was an additional rapid rise to around +9m. This clearly required more melt than at present even at the beginning of the LIG, followed after a long interval by a fairly abrupt further disintegration of ice sheets.
As Killian noted upthread, the ultimate rise required near complete melting of the Greenland Ice Sheet, and also around the periphery of Antarctica. There is at least one mechanism that can operate to produce rapid further melting even during a warm interglacial. I suspect we’re on track to find out what it is by experience before we succeed in arresting the process. There are several candidates, but I’m not aware that any has emerged as the culprit in the LIG.
Piotr says
John Pollack: As Killian noted upthread, the ultimate rise required near complete melting of the Greenland Ice Sheet
I am not sure about that – Christ et al. 2023 paper in Science (<a href= "https://www.science.org/doi/10.1126/science.ade4248", https://www.science.org/doi/10.1126/science.ade4248) seems to suggests that the last major melting of the Greenland Ice Sheet was ca 416 ky ago.
I.e. much earlier than your last interglacial. And even during that 416ky melting resulted in SLR of 1.4m.
John Pollack says
Thanks for the correction, Piotr. It was also the 416k event that Killian was referring to upthread.
However, I still think that most of the Greenland Ice Sheet would have to melt to get to +9m SLR, as well as some chunks off the Antarctic Ice Sheet.
Killian says
Piotr, their data *must* be incorrect. The new paper discussed in the article I linked found a complete or nearly-complete melt of Greenland 416k years ago. That’s 6 to 7 meters of SLR.
SL levels for that interglacial will need to be recalibrated – or the latest paper found to be flawed. Both cannot be true.
Piotr says
John Pollack “ Thanks for the correction, Piotr. It was also the 416k event that Killian was referring to upthread. However, I still think that most of the Greenland Ice Sheet would have to melt to get to +9m SLR
which opens the door to even more questions – why no ice-free Greenland in the subsequent interglacials, even though they seems to have HIGHER SL than 416k???
See: https://www.researchgate.net/figure/Modeled-global-sea-level-history-showing-several-glacial-interglacial-cycles-over-the_fig5_226009421
In fact, it looks like the melted greenland 416k seems to have … approx. todays SL
– while you “+9m SLR” is likely to apply to the last interglacial. (LIG) i.e. period WITHOUT major de-icing of Greenland.
Stranger still for the current extrapolation of deglacation rates onto the near future – the slope of SLR is steeper at LIG with ice on Greenland, than at 416k with ~ ice-free Greenland.
Obviously deglaciation of Greenland was NOT the reason for those 2m/century rates at LIG.
Another surprising to me thing on this graph is that (with somewhat of an exception for last Ice Maximum) – the maximum drops in SL during ice maxima preceding deglaciations – gets …. shallower and shallower with each cycle. meaning that there is more ice. Thus I would expect much more complete de-icing of Greenland in LIG – since having started from much higher SL it would have more time to melt Greenland ice, before the factors terminating interglacial kicked in, than the 416ky had.
All this is to say that during each deglaciation the factors affecting SLR may have been in different combination – so one should be very careful when extrapolation past RATES onto the future in which the drivers of change are very different than in the past.
Sabine says
Dear Barry,
about your issues “because my comment above is Censor-Deleted by GoogleyTubes (as per >70% for my science comments) ”
Look a while back I too was having my comments delayed on youtube videos. I was baffled. I rarely comment at all. I kept trying different things, and then something stuck me – it was the comments I made that included URLs in my comments.
See, I was making a comment and sharing good references for others to follow. But that in itself was the cause to have my comments deleted. I don’t know when Youtube changed their system to block such things, because in the past I don;t recall it ever being an issue.
Try it yourself – make two comments the same but include a website or youtube url in one, and see what happens when you post them.
Geoff Miell says
Sabine: – “Look a while back I too was having my comments delayed on youtube videos.”
Ditto. And also some comments simply deleted almost instantaneously.
‘Clean’ YouTube URLs seem to be okay but not too many in the single comment. “Clean’ URLs mean non-referred, shortest possible YouTube URLs.
Other URLs can be problematic. Some work; many don’t. I’ve found if one needs to refer to a paper then just quote the publication, date, author, title/headline, and don’t include the URL. If it’s a reference to a website, quote the website name, date, etc.
Twitter/X URLs seem to be a no-no.
Some people are loath to click on any links.
Piotr says
Tomas Kalisz: “I do not think that asking climate scientists for their comment (whether or not they see this knowledge gap as well) will somehow support despotic regimes”
On its own – not; in the context of your and JCM activity on this forum – it is:
Your never accepting answers that don’t fit your deniers narrative (“Anything but GHGs”) , your cherry-picking only those parts of answers that you can misrepresent as supporting your claims, and your incessant sealioning (“ a type of trolling [by] pursuing people with relentless requests for evidence, often tangential or previously addressed, while maintaining a pretense of civility and sincerity (“Thank you for your reply.”). It has been likened to a denial-of-service attack targeted at human beings – are all characteristics of a troll..
And since you. Tomas Kalisz, have been trying for more than a year to seed doubt in climate science, and distract the attention from the urgency of the reduction of GHGs – you are either a paid troll, or “ a useful idiot of fossil fuel oligarchy, and tyrannies that depend on petrodollars to sustain the regimes, enrich their robber barons, and project power abroad: by funding invasion of other countries, supporting extremists, and waging a hybrid war against the democracies.“..
By their fruits, not their protestations, you shall know them. Particularly that the lady doth protest too much.
Tomáš Kalisz says
in Re to Piotr, 12 Aug 2024 at 10:36 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823690
and in addition to my previous reply of 12 Aug 2024 at 3:34 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823694
to Piotr’s post of 11 Aug 2024 at 11:21 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823673
which is identical with the recent one.
Dear Piotr,
I think that, based on your repeated statement, I can now summarize the discussion as follows.
You believe that
1) my questions asked on this forum discredit climate science,
2) for this reason, joining my request to the hosts of this website would have enhanced the destructive effect of my questions and should be therefore avoided, even in case that the request perhaps could be relevant per se.
Please correct me if I misinterpreted your replies.
For the sake of clarity, I would like to summarize my position as well.
As I wrote in my previous reply, I believe that a sound, healthy science has to be aware of existing knowledge gaps, and strive to direct research thereto. I do not think that admitting the existence of knowledge gaps is a sign of weakness of an individual, an institution, or a discipline, and that it might undermine credibility thereof.
Rather oppositely – I see as quite suspicious, if someone perceives questions as a threat. In such cases, I will take any advice from this person and/or institution with a decent portion of caution.
I think we can close our exchange now, because there seems to be no common basis on which we could discuss. If I understood you correctly, there is no need for a continuation.
Best regards
Tomáš
David says
Tomáš, in reply to your response to me on 10 August:
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823654
.
You wrote: “As regards your question why I do not resolve my question(s) myself by my own research, I must reply that as a chemist, I do not have the necessary training for climate modeling. And, more importantly, I am afraid that doing any research of this kind is in fact beyond my capabilities.”
I owe you an apology. I was operating under an incorrect assumption regarding your motives as your statement to me that “your open question” is seeking an answer from “climate science professionals,” of which I am not, makes clear to me. You don’t understand why Real Climate’s (RC) haven’t responded to your pleas for addressing your “open question if there still may be a knowledge gap regarding the relationship between water availability for evaporation on one hand and climate sensitivity towards other forcings on the other hand…”
Your subsequent comments to Piotr and Radge Havers regarding your expectations of a reply from RC’s hosts are illuminating. As they both correctly point out, the hosts are under no obligations to offer replies to yours, mine, or any other commentators questions, pleas, or laments. Our hosts make no such claim that they will answer any or all inquiries. RC is a valuable and useful asset as is (including the monthly U.V.’s) and all the hosts have professional lives that keep them quite busy I would guess.
With this in mind, why you keep asking for a reply and expressing your dissatisfaction at not receiving one, and worse using a lack of a reply to make naked assumptions about the attitudes of RC’s hosts, other commentators here (if they won’t join your pleas), and the field of climate science in general, is patently unfair in my opinion.
As there are literally thousands of climate science professionals of one type or another around this old globe, I admit I’m curious to know if you have or are planning to put your questions to any others in the field? If so, please share your results when you receive such.
And if you’re not planning to ask your queries of others now or in the future, why is that?
Tomáš Kalisz says
In Re to David, 17 Aug 2024 at 4:05 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823798
Dear David,
If I unintentionally expressed my dissatisfaction with absence of a reply to my questions from the hosts of this website, I have to apologize. I do not think I have a right to assess them or their motives. Moreover, I have to say that I appreciate replies provided by other readers, even in case they disagree with me.
The were several reasons why I tried to to get answers repeatedly. Mostly it was a new knowledge that changed my view and led me to reformulation of my question, sometimes it was just a reaction to a repeated criticism directed to me.
As regards asking my questions elsewhere: I several times mentioned my previous attempts which I originally made on local level (Czech Republic, Slovakia). This way, I found out that some leading local climate science educators (presenting themselves as climate scientists) genuinely believe that latent heat flux cannot play a role in global average surface temperature regulation. Other local climate scientists that I approached stopped their exchange with me when I asked them if they could correct their colleagues in spreading misleading information to the public.
Two internationally notable climate scientists (of a few that I tried to approach) were, however, willing to reply my questions asked in this respect. One of them even confirmed that there is “lot of misunderstanding” among climate science educators as regards water cycle and latent heat flux role in global climate. I think that it was helpful that one of them is author of a standard physical climatology textbook which, although very briefly, expressly mentions the role of “turbulent fluxes” in global mean surface temperature regulation.
I think that I could now exploit the experience collected herein on Real Climate and try to approach these scientists again, with my yet open questions regarding the knowledge gaps that seem to exist e.g. with respect to relationship between water availability for evaporation and climate sensitivity.
I cannot promise, however, that they will reply, and even less I can promise that I will be able to share their personal views if they will be willing to provide them.
Greetings
Tomáš
David says
Tomáš,
Thank you for enlightening me re your previous attempts at conversing with local and regional climate educators and scientists and sharing that experience here at RC. If that sharing happened this year then I guess I missed it or saw it and subsequently forgot. It sucks to get old ;-) But thank you for taking the time and reiterating above.
I’ve relied on RC as a reference site and of course the hosts’ articles for quite some time. However, I only began to read the comments this year.
Cheers!
MA Rodger says
GISTEMP has reported for July with an anomaly of +1.21ºC, this a small drop on June’s +1.25ºC (but this only because June was adjusted up from the earlier published +1.21ºC).
And July 2024 becomes the 14th “scorchyisimo!!” month in-a-row, last July being slightly cooler at +1.19ºC. And with August 2023 also with an anomaly of +1.19ºC, a 15th “scorchyisimo!!” month in-a-row could be on the cards. (The daily ERA5 reanalysis at ClimatePulse have been showing the early August anomalies running up a bit.) Previous runs of “scorchyisimo!!” month in-a-row managed seven in 2015/16 and six in 1997/98.
NOAA has also posted for July (although the link is proving a bit lazy at present).
For the full calendar year 2024 to end up with a lower average than 2023, the Aug-Dec average anomaly would have to drop below +1.02ºC. In the times before the 2023 “bananas” anomalies, the warmest Aug-Dec were 2015 & 2019 at +0.99ºC.
But perhaps the level of cooling is more the measure of it.
Relative to the Jan-Jul average (+1.28ºC) that would be a drop of 0.26ºC. Past years have seen drops of 0.25ºC (2008), 0.20ºC (1998), 0.16ºC (2016), 0.15ºC (2006 & 2020) & 0.14ºC (2002).
Of relative to the Jan-Apr average (+1.34ºC) that would be a drop of 0.32ºC. Past tears have seen drops of 0.32ºC (2016) & 0.22ºC ( 2006, 2017 & 2020).
But in this post-‘bananas’ climate, pre-2023 years may not be good indicators of what to expect.
Pete best says
Where are we regarding accelerating climate change? Still evaluating or is the rate of warming increasing.
https://tamino.wordpress.com/2024/07/10/how-fast/
Mal Adapted says
Pete, Gavin posted on the apparent acceleration of the GMST trend last April. MA Rodger, a numbers guy for sure, contributed comments. I re-posted Tamino’s announcement on the July thread because I had the same question you do, after Gavin’s conclusion in April (emphasis his):
So, I’ve been expecting a showing of statistical detection. My last Statistics course was 40 years ago, so while Tamino’s posts always impress me with their thoroughness, attention to detail, and humility, I don’t try to follow his application of specific procedures. His plots are always crystal-clear, however. If he says
then I’m inclined to accept that as fact, albeit tentatively and provisionally, per scientific philosophy, culture, and practice. OTOH, I’ll happily defer to people such as MA Rodger, who is more qualified than I. Last month his comment was “I don’t see anything immediately new in the Tamino post.” I’m aware that theory predicts acceleration; it was the statistical confirmation of the prediction that was news to me. But Tamino himself finished his post with accustomed humility:
I’m left with a tentative, provisional increment of alarm that global warming has, in fact, accelerated, while watching for a consensus of Gavin’s and Tamino’s peers to form, and exhorting my fellow Americans to vote Democratic.
Pete best says
El Niño was over in May I believe and now it’s a neutral phase but 2024 is still warmer than 2023 so far. Could be the hottest year – should it be.? 2024 should be slightly cooler than 2023 which was peak El Niño.
It’s a close run thing but El Niño temporarily spikes global temps and then it should fall back slightly but even if it is int falling back as much as expected ?
That’s my angle
Ray Ladbury says
My own analysis supports the nonlinear increase of temperature over time. The past year’s result does influence the trend, but it’s significant even if you only include the past decade and not this past year.
I note however, that if you plot temperature vs. ln[CO2], the trend is still linear. This is not surprising, since the increase in CO2 is nonlinear (quadratic gives an excellent fit.). This suggests to me that we aren’t seen a fundamental change to the physics or feedbacks. [CO2] is still driving the show. However, this is not to say that at least some of the nonlinearity in [CO2] increase could not be the result of natural feedbacks. We know fires, melting permafrost, etc. are increasing, while the increasingly warm oceans are likely not as effective a sink as they once were.
Oh, and for the benefit of Weaktor et al., the R-squared for T vs. ln[CO2] exceeds 0.92.
Kevin McKinney says
Thanks, Pete. Shared the story.
zebra says
For Pete et al, which includes Tamino and Gavin and so on:
https://wmo.int/media/news/new-study-shows-earth-energy-imbalance
Yes or no question: Is “global warming” defined as GMST??? Is “climate change”???
If the goal is to educate “the public” and counteract the obfuscation from the usual suspects like the vaporheads, isn’t it time to offer a more disciplined and complete presentation?
David says
Propublica is out with yet another top-drawer piece of reporting, this time concerning training videos being used in furthering preparations towards implementing the various goals outlined in Heritage Foundation’s Project 2025.
One involves the disgusting anti-science, anti-democracy, and anti-humanity approach underpinning their plan for Trump and his incoming team to target all research and government action on climate change and to scrub the subject everywhere in the government.
Below are three links: one to the Propublica story, also from the story a 1:16 youtube exert taken from one of the training videos titled “Hidden Meanings: The Monsters in the Attic” in which Bethany Kozma calmly explains how this evil climate science stuff will be dealt with, and lastly the National Intelligence Estimate covering future risks arising from climate change that also draws her ire.
.
https://www.propublica.org/article/inside-project-2025-secret-training-videos-trump-election
.
https://youtu.be/7CgnMYUYpP8
.
https://www.dni.gov/files/ODNI/documents/assessments/NIE_Climate_Change_and_National_Security.pdf
.
.
Time now for a cocktail I think :-)
Kevin McKinney says
Time to work on “Mercury Rising,” in my case. But thanks for sharing, and I hope the cocktail was a good one.
Mal Adapted says
Wow, that’s pretty arrogant, Sabine. You sound like a couple of long-time RC regulars who are never content just to be right, they have to be the only ones who are! I, for one, am not worried about Project 2025, any more than I was about Agenda 21 in 2016. Both inspired conspiracist ideation, on the left and the right respectively. I personally have no problem with grandiose, aspirational proposals to remake the USA and the world. Talk is cheap, and our constitutional checks and balances have so far prevented outright dictatorship (more about that later). I’m not looking for a total program from decarbonization advocates, of which I’m one: I’ll settle for incremental collective interventions in the energy market, to take more and more of the profit out of selling fossil fuels until nobody’s investing in them any more because carbon-neutral energy is ubiquitous and cheap, whereupon the cumulative cost of global warming will be capped. If the rest of humanity’s impacts on the biosphere continue unabated, at least it will be in a stable climate!
I’m a little more disturbed by Trump’s assurances to Christian conservative supporters that they’ll never have to vote again if they vote for him this November. Sounds like dictatorial ambition to me! It’s infuriating, even if he isn’t actually capable of following through. The Democrats aren’t saints, and have their own historical collaboration with Big Carbon to answer for, but they’re clearly the lesser evil in this election! We’ll never get the government we really want, because our system isn’t designed that way; and whom can we trust to lead a change without making things worse?
As for your contemptuous declarations that the rest of us are all naive dupes of carbon capital: The decades-long investment by fossil fuel producers and investors in propaganda and undue political influence, to thwart collective intervention in their profit streams, is common knowledge on RC. What makes you think you know something the rest of us don’t? You do understand that the IRA of 2022 was the first federal policy enacted to begin decarbonizing the US economy since Jim Hansen’s Congressional appearance in 1998, don’t you? The IRA is hardly going to bankrupt the Koch club by itself, but its symbolic importance is huge IMO. It passed on the slimmest of Democratic majorities. A Republican victory this fall threatens to reverse even that baby step. A Democratic victory offers hope for strengthening and extending our collective decarbonization policy. But politics is the art of the possible. We should all be doing whatever we can to undermine the petro-plutocracy, but we can’t expect to win that war in one fell swoop, because $trillions in annual profits can buy a lot of votes. Casting ours for Harris/Walz is literally the least we can do!
Sabine: “all the Democrats are doing is rearranging the life boats on the Titanic.”
Too dogmatic, IMHO. What Democrats are doing is more like trying to slow down the Titanic before it hits the iceberg, while a loud group of Republican officers and passengers keeps shouting “What iceberg? Full speed ahead!”, and a handful of leftists tries to grab the wheel. Gotta love metaphor. With more moderate Democratic hands on the levers of power, the ship just might make it to shore before it sinks. The passengers won’t ever get back to where they came from, but at least they’ll be alive. Perfect is the enemy of survival!
I respectfully request that you view yourself from our perspective. You’re not the only one thinking hard about this. If what you want is to cap the cost of global warming at the lowest possible total in money and tragedy, well, most of us want that too. We all know who the actual denialists here are when we see them. Let’s reserve our enmity for them.
Kevin McKinney says
JCM, you say:
Well, I find it hard to imagine that, too. But apparently you don’t, because you are apparently under the misapprehension that somebody here actually is saying that. That’s not correct, unless I’m deeply mistaken.
What many, including me, have said is that:
1) It is imperative to stop the increase in GMST;
2) That to do that it is imperative to stop the increase in what you persist in calling “trace gas” (GHG) concentrations.*
We have NOT said that this will address all ecological problems. We do NOT oppose conservation of wetlands, old-growth forests, native grasslands, peatlands, or any other ecosystems you might care to name. In fact, quite the contrary.
On the other side of the ledger–and going back to point #2 above–we do say that on present evidence it seems highly unlikely that trying to stop increasing GMST by conserving wetlands is going to be effective. It may be–I would say very definitely IS–desirable on its own terms. We do indeed have an extinction crisis, and it has multiple drivers, not the least of which is straight-up habitat loss. But that case is best made on its own terms–not using the justification of slowing global warming, which is likely quite specious.
(And, be it noted, also thereby muddying the waters as far as messaging the public.)
JCM says
Thanks McKinney. I agree the most pronounced co-benefit of conservation stewardship from a climate perspective is reduced hydrological and temperature extremes. Across different forums, particularly in person at farm stewardship workshops, I don’t make any mention of GMST. There the most sought after subject is nutrient management and sediment export. However, on these pages, I was told some time ago that the key values of interest to participants are GMST (or GSAT or similar) and global policy recommendations. So, I try to align my contributions with that framework here. Cheers.
Mal Adapted says
Thank you, Kevin. You ably represent the climate-science consensus supporters among RC’s commenters, who understand that global warming has multiple, hierarchical causes from ultimate to proximate, arising from the overlapping knowledge domains of physical science, ecology and evolution, economics, anthropology, psychology, sociology, political science, and above all, human history. We focus on the anthropogenic physical causes, primarily but not limited to “trace gases”, because that’s the announced topic of this blog, and it’s where RC’s authors and many regular commenters have some training and expertise! Many of us have definite ideas about the ultimate causes of all the ancient insults and injustices humans have inflicted on the biosphere and each other. Many of us also have definite ideas regarding What Is to Be Done about it all. We do occasionally discuss those ideas here, but tend to shy away from them because they are highly subjective, and tend to provoke weeks of pointless off-topic drama! In addition, few of us have enough exposure to everything that’s known about the diverse causes of global warming and the uniquely contingent history thereof, to expose ourselves to ridicule by other RC regulars: a sort of informal peer review!
OTOH, the warrant for RC’s monthly UV thread is broad. JCM, and Sabine (surname unknown) represent people who view the long history of our unsustainable behavior toward the earth and each other from a passionately humanistic perspective. Both appear incompletely informed on certain scientific aspects of our global predicament, but their passion is the underlying message in their comments. The heck with scientific reticence and the principle of least drama! They have strong moral opinions about the way people ought to behave “sustainably” by their subjective definitions. Everyone is an expert on their personal morality. However, collective action to reduce our “environmental” impacts as a population is within the domains of the behavioral sciences, about which I presume few of us are experts. Both JCM and several-comment Sabine claim to know crucial facts we don’t, and seem angry that we don’t explicitly recognize their superior knowledge and endorse their prescriptive solutions, forsaking much we’ve been at great pains to learn. The pair are almost certainly wrong about the efficacy of their preferred remedies, but at least they’re confident!
Yet neither JCM nor surly Sabine are climate-change deniers, unlike so many of the antagonistic pseudo-skeptics who show up here. It’s a novel experience for me, at least. I’ve actually learned a few things, from JCM especially, despite his rejection of both the CO2 greenhouse effect and the principle of least drama. Both of them are mitigation alarmists, although not obvious lukewarmers; I for one find their mitigation proposals rather alarming, however. I’m reasonably confident neither has the wherewithal to implement their programs, because they don’t appear to recognize that “Politics is the art of the possible, the attainable — the art of the next best” (Otto von Bismarck), or that perfect is the enemy of better-than-it-is-now! It’s uncertain that incremental, targeted collective action to take the profit out of selling fossil fuels can fully decarbonize the global economy, in the time we have left for collective action on a scale larger than a fortified town; nonetheless, I have no doubt that global heat content will rise until we accomplish it. Nor am I happy about the environmental impacts of producing carbon-neutral energy for 8 billion people. But I’m convinced that without capping the 300-year anthropogenic upward trend of trace gases in the atmosphere, no other collective action to mitigate multiple tragedies of the commons can succeed for long, and will eventually be impossible. Of course Democrats aren’t pure of heart, for “Out of the crooked timber of humanity, no straight thing was ever made”(Immanuel Kant). They are, however, clearly the lesser evil here and now!
zebra says
Kevin M,
No, it’s Physics Cop.
Real science is moving on.
https://essd.copernicus.org/articles/15/1675/2023/
But here we have people who should know better participating in rhetorical word games with the last desperate vaporhead denialist types, the pages filled with the same nonsense repeated over and over.
And in the real world, real people are accumulating their own data… breathing the smoke from fires, and drowning in downpours, and succumbing to excess heat. But I’m sure they really care about the statistical nuances of GMST, a variable which has no effect on anything.
Time to move on.
Barton Paul Levenson says
z: But I’m sure they really care about the statistical nuances of GMST, a variable which has no effect on anything.
BPL: The variable “your weight” has no effect on anything, either, but the medical condition it suggests can have profound meaning. Don’t confuse the measurement with what it’s measuring.
zebra says
BPL
“The variable “your weight” has no effect on anything, either, but the medical condition it suggests can have profound meaning. ”
???
No, not even close as an analogy, and incorrect as well, physics-wise.
“Don’t confuse the measurement with what it’s measuring.”
That’s the point of what I said to Kevin!
And I would wager 98% of the public that accepts the concept of climate change is doing exactly that, because of sloppy communication even by the professionals.
The real point is illustrated by the reference I gave… did you at least scan it?
GMST has obviously been useful as a proxy for increasing overall system energy, but now we can determine that directly, as well as for sub-systems. Seems to me the “climate blog by climate scientists” should, as I said, be moving on.
jgnfld says
Bit of a nit, but needs clarity given all the stats BS we see here from some: While things can get rather more complex with such techniques as path and mediating variable analysis (of old), various autocorrelations from feedbacks/feedforwards, machine learning, etc of today, one thing should be pretty clear: Observations of final dependent measures actually should either (1) NOT have effects on the input variables or (2) HAVE measurable and partitionable feedback parameters.
zebra says
“It is imperative to stop the increase in GMST.”
No Kevin, it isn’t. It is imperative to stop the increase in climate system energy, as quickly as possible. That means achieving a balance in incoming and outgoing radiation.
But I guess if you said it that way, you couldn’t keep these inane, repetitive, pretend-science discussions going, on and on and on.
Kevin McKinney says
Speaking of inane, repetitive, pretend-science… spiced with inane, repetitive, and highly pretentious Language Cop nonsense…
Mal Adapted says
Huh. Looks like the comment of surly Sabine’s I responded to has been deleted.
alan says
Yes, and quite annoying for readers (like me) who have to go back and forth trying to figure out WTF you are responding to.
Moderators: for the love of God, if you want to censor/delete posts, fine; do so BEFORE YOU ALLOW THEM TO BE POSTED. Thank you.
Susan Anderson says
@alan – I can’t help with the Sabine, though you can get a flavor from her (his?) other comments, which on the whole are a waste of time and energy. However, here’s the ProPublica, and you can see that a number of us find it one of the best research/public service information resources around. I know the outrage factor seems over the top, but there’s an awful lot to be outraged about, and their work is reliable. Main site ->
https://www.propublica.org/
Item in question:
https://www.propublica.org/article/inside-project-2025-secret-training-videos-trump-election
I put myself on their mailing list long ago, have to admit there’s so much ‘bad’ news there I had to go back to my inbox to find the relevant item.
As for strictures on moderation, my impression is that they’re overworked and have day jobs, so in general not much moderation occurs. If I were to guess, the community’s outraged reaction and perhaps some rare over the top disinformation caused this unusual post facto deletion.
As ‘for the love of god’ – note that this comment section is full of good, bad, and indifferent material, and endless arguments therefrom, so I wouldn’t invest my emotional (or spiritual) well being in knowing who’s talking about what.
Mal Adapted says
Susan:
Nice. With apologies to everyone including Gordon Lightfoot, I can’t resist:
Wreck of the Edmund Fitzgerald
Susan Anderson says
The insult-filled response from Sabine contains multitudes in the matter of contradictions, peculiar and inconsistent. Though S claims we don’t read, she appears not to have read the ProPublica article, which is much shorter than Project 2025’s many pages (an earlier version was 887 pp and other lengths are cited).
ProPublica is one of the finest news resources in the world. I became familiar with them when Abrahm Lustgarten did in-depth work on the Colorado River: https://www.propublica.org/series/killing-the-colorado … He has moved on and his recent book On the Move is superb. https://yaleclimateconnections.org/2024/04/book-review-on-the-move-is-a-must-read-account-of-u-s-climate-migration/
As long as I’m here, another superb Jeff Masters review: The U.S. is nowhere near ready for climate change: Despite recent investments in adaptation, the U.S. remains woefully unprepared for the coming extreme storms and floods. – https://yaleclimateconnections.org/2024/06/the-u-s-is-nowhere-near-ready-for-climate-change/ … One can acknowledge we’re not doing enough without making things worse by making an an excuse to replace those who are trying with those eager to deceive, cheat, profit, and blame victims.
Yes, the current Democratic administration has terrible stats on actual cutbacks of fossil fuel extraction and use. Their compromises are driven by the realities of democracy in action where doing the least bad is all that’s available. That is no excuse for electing the worst. It should be a driving force to get rid of all corrupt liars in our legislatures and courts, and to get a majority large enough to reform SCOTUS.
Spewing bile about our hosts here at RC and those trying to do what they can is both contemptible and wasteful.
Sabine would do better to absorb Jane Mayer’s Dark Money (also the earlier Chris Mooney’s Republican War on Science). Rachel Maddow’s Blowout is superb on the influence games of the extraction industry. Anything from ProPublica is likely to be well researched and reliable, as is Inside Climate News.
Tomáš Kalisz says
In Re to Susan Anderson, 14 Aug 2024 at 10:03 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823734
Dear Ms. Anderson,
I have a feeling that the content published by Sabine and even more her style remarkably resemble the person who was very active on this forum under a nick “Ned Kelly” and then suddenly disappeared.
Best regards
Tomáš Kalisz
Susan Anderson says
TK: No. NK’s style and content were different. There are plenty of other bores and cranks in a variety of flavors here (and, as is sometimes noted, arguing here is a substitute for doing something real in most cases), but I’m guessing our collective complaints about NK’s massive body of work overwhelming any reasonable back and forth here were heeded.
K McK (and others): The relevant Sabine comment does appear to have been removed. That’s interesting. Perhaps some more active removal of some of the more extreme provocations happened. [I checked both crank shaft and bore hole and they’re not there. I guess there comes a time when timewasting is simply not worth it any more.]
After all, we do have community guidelines and if we don’t follow ’em, it’s not surprising if there are consequences. AFAICT it’s not about the links, it’s about the obnoxity.
Radge Havers says
Thank you, SA.
Looks like there’s yet another troll sock puppet on the loose.
Kevin McKinney says
Not seeing a comment fitting that description. Did it get moderated off to the Borehole or Crankshaft, perchance?
Kevin McKinney says
Actually, I find that the Borehole seems now to exist only in some archives, while I found no trace of the Crankshaft at all. Unless, of course, I stopped looking too soon, which is not impossible.
Nigelj says
Kevin. Go to the list of archvives by category. The bore hole and crank shaft are right at the end of the list. If you click on them and get a largely blank page, click on the title bore hole or crank shaft on the blank page a second time and the comments appear.
Nothing in there by Sabine. Her comment just seemed to get deleted.
Kevin McKinney says
Nigel, thanks. I can find the categories where you describe them, but click as I might, no actual post appears. I did get to the Bore Hole via a search result, and saw some items from as recently as last year, but nothing since.
But really, no matter AFAIAC. I was pursuing it for mere idle curiosity.
Mal Adapted says
I thought I was the only one puzzled by the missing provocation from Sabine (the one who isn’t Dr. Hossenfelder). Yeah, David’s mention of ProPublica set her off. Her truculent reaction was here for a couple of days, but no longer appears, leaving our subsequent replies without a challenge to reply to! The removal was presumably intentional, as many (all?) of her previous comments are still in place. They evince her growing resentment, but none were quite as unhinged as the missing one. I expect we’ll never know, however.
Both the Borehole and the Crankshaft are now just empty bit buckets, AFAICT. Once again, my sympathies are with the moderators.
Silvia Leahu-Aluas says
Yes, Susan, I completely agree. There should be no hesitation in electing the social-democrats/liberals/center/progressives, a.k.a.the D party, as opposed to the reactionaries. The upcoming Democratic administration will be more progressive, as this is where their base and the majority of voters are. I am convinced that we will see more of the Green New Deal implemented.
Hopefully, voters will decide on policy and the politics of delivery for the common good, not of theatrics, no matter how much the media, in all forms, stay trapped in the latter, with few exceptions. ProPublica is one exceptional exception; “Investigative Journalism in the Public Interest”
alan says
I want to read the “insult-filled response from Sabine” because I want to know what the hell is going on here, and what Susan Anderson is replying to.
For example, Anderson writes that Sabine “appears not to have read the ProPublica article”. WHAT ProPublica article? One cited by Sabine? How can I find it? How can I read Sabine’s post?
This *post hoc* deletion (after the fact deletion of posts; pun not intended) is extremely annoying.
Radge Havers says
This is still a moderated site, even though the hosts are busy with other things. Cut them some slack.
FWIW, it appears that, in order to get a comment deleted here, you have to troll pretty hard and succeed in being disruptive. Add to that that Sabine was likely a sock puppet of a previous troll who had already wasted an inordinate amount of space and time here being a jerk for the sake of being a jerk.
IMO there’s no point giving someone like that oxygen, and frankly you’re not missing anything from what’s been deleted– especially since there are more interesting things here to focus on.
If you’re curious, note that although the borehole and crankshaft seem to have been relegated to inactive archives, you can still check them out to get a sense of the kind of stuff that has historically been considered too ridiculous for adults to waste time on.
Mal Adapted says
This is why it’s wise to lurk on a blog for a time before putting one’s 2¢ in. If it’s any consolation, this is the first time I can recall that happening without explanation on this blog in years, if ever. The rare removals of comments have always been preceded by warnings. Like multiple otters (but not sea lions), I reacted negatively to singly-named Sabine’s attack on ProPublica and our collective credulity. Her comment was childishly offensive [Hey, I resemble that remark! MA], but I didn’t think it was that bad, at worst nothing legally actionable. We’ve all seen worse here from time to time, and sometimes have managed to expel certain intolerable irritants decisively, but none of us but the moderators have the ability to delete comments! AFAICT that’s the only one of her multiple comments that’s no longer accessible. I did notice that all comments by “Bok” are missing, from last month’s UV thread as well as this one. Again, AFAICT they weren’t offensive at all. The puzzle waxes!
I’m baffled too, but I’m pretty sure if Gavin and colleagues had anything to do with it, they’d tell us. If not, they’ve all got better things to do anyway. Lurk and learn.
Sabine says
@MA Rodger says
12 Aug 2024 at 8:07 AM
I am not that Sabine. A typo may have sent you astray. I read your comment, and am none the wiser. I recommend you review her commentary more closely:
eg
“So whom can you trust? Trust no one. What you can trust for the most
part is: data, maths, and logic. At least in the physical sciences,
and I count climate science as physics, it’s incredibly rare for data to be wrong
or fraudulent, and for that to remain undiscovered. It happens, but it’s rare.
It’s likewise rare that maths or statistical analysis is just wrong, and for that not to be
criticised or corrected. Indeed, the problem in the foundations of physis is not that the data
or maths is wrong, it’s that they have no data, and the maths isn’t about anything in particular.
And finally, there’s logic. Logic is your friend. Trust arguments, not people. ”
imo too many people (scientists) are focusing on minutia, like monthly and yearly data and anomalies and statistical graphs, when the real science about global warming, global temperatures, massive changes in the climate and SLR are actually about DEEP TIME on a planetary scale. And too much data is missing and not being considered logically.
So it’s not really about acceleration over a short period of time, or net zero by 2050 or anything like that, or this months anomalies or this years Global Mean Surface Temperatures, or who wins the US election in November.
No one (sane) has said SLR will increase by +5 metres by 2100. Or 2025 to 2125. Or 200 to 2150. 2100 is NOT Deep Time either. Nor is a century. The current warming rate is multiple times faster than any of the last warming of post glacial periods over millennia. Hansen is right iow, or at least more right because he uses better data and logic.
Watch Sabine’s video again, I believe you missed all her key points of what really matters re the Science and Scientists and why none of them should be trusted or believed. See quote above again. Good luck.
MA Rodger says
Sabine,
Regarding the video of your namesake, I clearly remember the quote you provide & am not sure what a would be gained if I “review her commentary more closely.” And if I did miss “all her key points” (which would be a surprise) perhaps you could set them out. What I do struggle-with is what you mean by “DEEP TIME on a planetary scale” and I do not understand what it is you mean specifically by “too much data is missing and not being considered logically.”
This “deep time” appears to concern periods far longer than a century (which is too-long a period for action to cut emissions to Net Zero) although such a timescale is applicable for consideration of SLR which takes eventually millenia to run its course.
The idea of +5m SLR by 2100 should not be seen as entirely insane without some initial consideration and indeed has been projected in published papers. (So not “no one” although it is not quite the same as them saying “SLR will increase by +5 metres by 2100”).
Specific to ‘+5m SLR by 2100’:-
A decade-plus ago, the various SLR analyses were always calculating a limit to 2100 SLR at roughly 1m.
But then an outlier appeared with a 2100 5m projection. Hansen (2007) ‘Scientific reticence and sea level rise’
Sudden SLR rise has been seen in paleoclimate studies (Meltwater Pulse 1a saw multi-metre SLR per century or multi-centimetre SLR/yr, this in a world with a lot more ice) and that leads to the worry that Antarctica could suddenly begin quickly shedding ice with just modest levels of AGW. But this proposed idea of decadal doubling-times continuing for a century appears unsustainable. The 1mm/yr SLR polar ice component of SLR would become 512mm/yr by 2100 with a 10yr doubling-time. The energy requirements to melt 180,000 cu km of ice per year would be 100% of the forcing from a doubling of CO2. So, while not an entirely-insane energy requirement, this energy does somehow need directing to the ice (or the ice to it).
A partial exploration of such a process was eventually set out in Hansen et al (2016) ‘Ice melt, sea level rise and superstorms’. However it only assumed various doublings (including annual multi-decimetre SLR) so as to then model the climatic implications. What is missing is any substantial basis for annual multi-decimetre SLR. A multi-metre SLR over millenia resulting from a +2ºC warming is not contraversial. (IPCC AR5 Fig13.14 shows an equilibrium SLR of +4.2m/ºC plus +5m from Greenland melting down which is the expected equilibrium result for AGW less than +2ºC.) Hansen et al (2016) admits the doubling profile cannot be properly inferred from recent data and thus the idea that such ice melt/calving could be achieved is solely supported (I consider mistakenly) by Pollard et al (2015) which only shows +30mm/yr SLR resulting from Antarctic melt/calving (from +2ºC SST = roughly +4ºC SAT) which is nowhere near annual multi-decimetre SLR. Another reference (Hansen et al 1984) appears to be suggesting it is temperature rise which is unstable due to interactng feedbacks, and that this in turn drives massive SLR. But that is a whole different argument.
Tomáš Kalisz says
A question in Re to MA Rodger, 15 Aug 2024 at 1:14 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823769
Dear MA Riodger,
Thank you for your analysis!
It appears that the crucial point that may be decisive for the assessment if the rapid multi-metre sea level rise till the end of this century may or may not be physically possible are the following questions:
1) Is there a sufficient energy source (or, perhaps, a sufficiernt energy reserve already stored in the system – e.g. in form of heat already accumulated in ocean) that could enable the considered melting of the necessary amount of ice?
2) Is there a mechanism how this amount of energy could be distributed quickly enough to the available ice to enable the assumed ice melting?
From your reference to the Meltwater Pulse 1a, it can be construed that under different circumstances (lower greenhouse effect, different insolation distribution over the globe, higher amount of available ice), a such rapid ice melting already happened.
Are there some studies that clarified the mechanisms which enabled this impressive melting / SLR speed during the Meltwater Pulse 1a? If so, I think their approach could provide a clue to the question if a such rapid melting is possible nowadays as well. If not, then I think that focusing scientific effort in this direction might be quite desirable.
Greetings
Tomáš
MA Rodger says
Tomáš Kalisz,
This +5m SLR by 2100 idea has usually been attached to Hansen’s notion of doubling the net polar ice-melt multiple times. Thus the present-day +1mm/year SLR from polar-ice melt could grow to become multi-decimetres/yr by 2100 – upward of 300mm/yr to approach that +5m SLR by 2100. So that would be [ 300 x 361 =] 108.300 cu km of ice per year requiring 33Zj to melt. Globally, that is 2W/m^2, equal to half the global forcing of double CO2.
You asked “Is there a sufficient energy source?” There’s masses of energy flying round planet Earth. For instance, there is the 160Wm^-2 absorbed by the surface from the sun. But such energy needs to be diverted from where it goes today and applied to melting ice. One of the ways of finding 33Zj/yr is by cooling the planet and increasing the Earth’s Energy Imbalance. This is what was modelled by Hansen et al (2016) when they impose the 5-yr, 10-yr and 20-yr doubling times to ice-melt and showed a 3.5ºC drop in global temperature and a +2.5Wm^-2 increase in the EEI. But that was modelling the effect not the cause.
Hansen et al say, “A sea level rise of 5 m in a century is about the most extreme in the paleo-record (Fairbanks, 1989; Deschamps et al., 2012), but the assumed 21st century climate forcing is also more rapidly growing than any known natural forcing.”
Those “most extreme” SLR in the references work out as 40mm/yr (Fairbank’s “maximum rates of 14,000 km^2/yr”) and a meaty 180mm/yr (18m in a century) is described as “extreme but possible” by Deschamps et al but also with 50mm/yr presented supported by other evidence. And these SLR rates being measures of Melt Water Pulse 1A, the relative level of forcing back 14kya is surely immaterial.
In the absence of 14,000km^2 (or multiples thereof) waiting to discharge into the oceans, I would suggest the mechanism we need to fear is a truly massive discharge of icebergs which can then float off to melt at warmer latitudes. However I don’t so far see any work projecting such a doomsday scenario.
Of course, the equilibrium SLR from AGW is already multi-metre (over millennia) so reducing GHG levels will be required if we are not to drown a significant portion of human real estate.
Tomáš Kalisz says
in Re to MA Rodger, 23 Aug 2024 at 7:01 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823938
Dear MAR,
Many thanks for your additional information, and apology for the late response.
Best regards
Tomáš
Tomáš Kalisz says
In addition to my question of 19 Aug 2024 at 3:07 AM:
Dear MA Rodger,
Piotr, 18 Aug 2024 at 6:40 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823830
mentions breaking giant ice dams and quick release of huge amounts of melt water accumulated over centuries in giant lakes behind these dams into the ocean as the mechanism of the very rapid Meltwater Pulse 1a.
This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR. I would appreciate your kind comment anyway.
Apologies for the overlooked typo in your name.
Piotr says
Tomas Kalisz – “ Dear MA Rodger, Piotr, mentions breaking giant ice dams and quick release of huge amounts of melt water accumulated over centuries in giant lakes behind these dams into the ocean as the mechanism of the very rapid Meltwater Pulse 1a.
This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.
Aga-baga? Don’t you understand ANYTHING your read, Tomas??? My argument argues the very OPPOSITE to what you claim it does! Specifically:
I said that multimeter SLR in the past, are not a good model for the potential future SLR rates – because they were caused by the specific conditions that are ABSENT today: by the collapse of ice dams, which released the meltwater accumulated on land over centuries. Today, NEITHER Greenland nor Antarctica has such giant lakes, waiting to break through the ice and add rapidly to the SLR. This makes the likelihood of “the rapid multi-metre SLR” in the near future LESS, NOT “more” likely, as you claim.
Don’t you have some remedial reading courses in Czechia?
Tomáš Kalisz says
in Re to Piotr, 21 Aug 2024 at 4:33 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823912
Hallo Piotr,
I accept your objection, although I think it rather fits my writing skills than my reading.
In my original sentence
“the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR” ,
I strived to express my satisfaction that the present situation significantly differs from the situation that led to the very rapid multi-metre sea level rise in the intergalcial, and that in this view, the threat of a such rapid multi-metre SLR till the end of this century may be in fact not as bad / as serious as some regular Real Climate readers, e.g. Geoff Miell, are afraid.
I am sorry for drafting my sentence the way that confused you.
Greetings
Tomáš
Piotr says
TK: “I accept your objection, although I think it rather fits my writing skills than my reading”
No, your writing, even though pretentious. meandering, and avoiding answering the direct questions is one thing – the fact you often COMPLETELY misrepresent post you read , and you “answer” is rarely if ever on a subject – indicates your inability to read / comprehend the texts you comment. In the above case – after my cautioning against extrapolation past SLR onto a very different future – you “understood” as =my supporting such extrapolation (“ suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.
In other words – you could NOT HAVE MISUNDERSTOOD my text more. Hence:
“Don’t you have some remedial reading courses in Czechia?“
Tomáš Kalisz says
In re to Piotr, 23 AUG 2024 AT 9:03 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823948
Dear Piotr,
I have explained that I understood your post exactly as you meant it.
If you are not a telepat, please be so kind and desist from asserting what other people read or misread.
Best regards
Tomáš
Piotr says
Re: Tomas Kalisz Au.25:
No, Mr. Kalisz, I does not take a “ telepat” to be able to read what you wrote and notice that IN YOUR WRITING you completely misrepresent my argument. As I wrote it in the post to which you reply:
===
P, Aug. 23 – “I cautioned against extrapolation past SLR onto a very different future
– you present it as … my supporting such extrapolation (“suggest that the situation might be more favourable now [for] the rapid multi-metre SLR“)
==
Then, I gave you the benefit of the doubt – that you didn’t understand my argument. But since NOW you insist that you “ understood your post exactly as [I] meant it“, then it means that you KNOWINGLY mispresented my arguments as OPPOSITE to what you KNEW they were.
In other words, that you, Tomas Kalisz, are a LIAR who DELIBERATELY misrepresents other people arguments.
And no, your pathetic attempts at legalese (“desist from asserting“) won’t stop me for calling you what you’ve proven with your posts to be.
Tomáš Kalisz says
In Re to Piotr, 27 Aug 2024 at 7:47 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824041
Hallo Piotr,
In my post of 19 Aug 2024 at 3:33 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823836 ,
I wrote:
“This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.”
Are you sure that your transcription of my sentence,
“This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
which you take as a basis for your objections, is equivalent to my original?
I have a feeling that, for example, the word “threat” that in my opinion plays relatively important role in my sentence, got somehow lost in your translation :-)
Greetings
Tomáš
Piotr says
Kalisz Aug. 27:
Are you sure that your transcription of my sentence,
– “This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.” [as]
– “This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
which you take as a basis for your objections, is equivalent to my original?
Yes, I am sure – “at least as regards the discussed threat” is just a chaff that changes nothing. As attested by the fact – that my response:
====
“Aga-baga? Don’t you understand ANYTHING your read, Tomas??? My argument argues the very OPPOSITE to what you claim it does! Specifically: I said that multimeter SLR in the past, are not a good model for the potential future SLR rates – because they were caused by the specific conditions that are ABSENT today”
===
applies EQUALLY WELL to your “original” as to the cleaned-up summary of it by me.
Tomáš Kalisz says
In Re to Piotr, 28 AUG 2024 AT 2:12 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824084
Dear Piotr,
Your English is much better than mine, so you also have to know better if my sentence and your transcript are equivalent or not.
Unfortunately, I have a bitter feeling that when you fight a perceived enemy, you are, with a clear consciousness, able to assert that sentences “Milost, nelze popravit.” and “Milost nelze, popravit.” are equivalent too, because the comma is just a chaff and changes nothing…
Greetings
Tomáš
Piotr says
Re Tomas Kalisz Aug.29.
Dishonest analogy – in your example, the change in the position of a comma changed everything, In my post – my replacing the highlighted words with “for”:
– “This seems to indeed suggest that the situation might be more favourable now [ at least as regards the discussed threat of ] [for] the rapid multi-metre SLR.”
changes NOTHING, other than making your (false) claim it less meandering. Hence your insinuation of my misrepresenting your words is, as usually with your insinuations, baseless.
And your littering your sentences with words that contribute nothing to your argument – is not a problem of your English, but of clarity of your thinking/writing. I’d bet your Czech is as intellectually undisciplined, pretentious, and lacking self-awareness as is your English.
You can tell a lot about people by the language they use.
Tomáš Kalisz says
In re to Piotr, 29 Aug 2024 at 7:54 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824128
Dear Piotr,
Thank you for your reply.
My Czech example was only to explain how I perceive your arguments – I doubt that anyone else read it except you.
I’m happy to admit that my originall sentence was ambiguous, but I’m still reluctant to believe your claim that it meant the exact opposite of what you wrote in your post (and what I intended to confirm / to agree with).
Anyway, I think that we can and should close this exchange now.
Greetings
Tomáš
Piotr says
Tomas Kalisz Aug. 30 – I’m happy to admit that my originall sentence was ambiguous
It wasn’t ambiguous – it was poorly written, loaded with chaff that adds NOTHING to your point, thus a product of undisciplined, sloppy, mind. But we already know it about you – so it that wasn’t my objection – I objected to your insinuation that my quote distorted the meaning of your words:
>> original – “This seems to indeed suggest that the situation might be more favourable now, at least as regards the discussed threat of the rapid multi-metre SLR.”
>> my shortened version: – “This seems to indeed suggest that the situation might be more favourable now [for] the rapid multi-metre SLR.” ,
I asked you to put your money where your mouth is – to demonstrate HOW the omission of the highlighted words – significantly CHANGED the point you were making. You didn’t, nor did you apologize for the insinuation you were not able to prove.
Until you honestly own up for your actions – I don’t see the point of answering your subsequent questions as if nothing has happened.
Tomáš Kalisz says
In Re to Piotr, 30 Aug 2024 at 1:55 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824167
Dear Piotr,
Thank you for your explanation.
If your transcription of my sentence is correct, I apologize that I have not believed you that my sentence has in fact an opposite meaning as I thought and that I suspected you from a deliberate manipulation with my words.
Greetings
Tomáš
JCM says
To Tomas,
Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”.
Obviously this directly opposes the bizarre distortions on display by respondents. Global landscape hydrology is a huge known information gap which is increasingly recognized. When detractors say things like “both of you REFUSE to acknowledge the conclusions” it doesn’t make any sense at all. They have it totally backwards. The so-called answers are completely fabricated and unsupported. Additionally, regressing back into arguments such as “given how small human impact is compared to the volume of global water cycle, and how short the residence time of water vapour in the atm is (~ week)” suggests detractors have not yet understood the idea at all. How is that even possible?
I recommend to avoid getting sucked into an endless vortex of nonsense if at all possible. Repeatedly pointing out the same falsehoods over and over again is usless. It should be time to move forward as Lague was initially introduced simply on the request to supply a quantitative analysis why Piotr and co were totally wrong to imagine that catchment stability is inversely related to climate stability. Ongoing uninformed and butchered attempts to rationalize a fixed ideological opposition to terrestrial biogeophysical process considerations to realclimate observables is misguided
For clarity, the suggestion that support for the values of landscape appreciation and research automatically means opposition to trace gas abatement is totally false. As previously mentioned, even Johan Rockström @ Potsdam is saying trace gas cuts will never be enough because systems are changing for numerous compounding reasons. This is so simple to understand and non-threatening. It is truly hard to imagine denying or actively minimizing this due to an artificial fixation on trace gas.
For instance, it is increasingly recognized that the significant declines in the resilience of systems like the Amazon are not primarily caused by trace gases: ‘Observation-inferred resilience loss of the Amazon rainforest’ (https://esd.copernicus.org/articles/15/913/2024/) states, ‘the results presented here suggest that [GHG], as a major historical and future forcing in models, plays a minor role in the observed rapid decline in rainforest extent. Mitigation strategies to limit future rainforest loss could therefore be most effective when focusing on other, human-induced stress factors.’
Can you believe it? Recent complex models in July 2024 have re-discovered that stopping direct ecological destruction is an effective way to prevent ecological destruction. The recent defacto hypothesis that dramatic changes should be abated exclusively with trace gas abatement is misconceived.
There are other references as well: ‘Agricultural expansion dominates climate changes in southeastern Amazonia: the overlooked non-GHG forcing’ (Environ. Res. Lett., 10, 104015, https://doi.org/10.1088/1748-9326/10/10/104015).
The literature has long acknowledged what is obvious to many: trace gas reduction is essential for achieving stability, but it alone will not stop the change. Lague’s work demonstrates that the CESM can produce a global response from terrestrial change alone. This is encouraging for the value of ESM-style models and is especially exciting given the disproportionate emphasis placed on global-scale computational analysis for globally significant policy advice.
The message is simple using current-generation models: climates will change with major and minor trace gas emission, and they will change even more with direct biogeophysical destruction. This is so simple to understand.
I suspect that the rigid opposition might be a collateral effect of misinterpretations and an inability to appropriately contextualize teachings like Genevieve Guenther’s ‘The Language of Climate Politics – Fossil Fuel Propaganda and How to Fight It’ or Mann’s ‘The New Climate War.’ I doubt these authors intended for uninformed extremists to take up this fight in the way some are doing. Frankly, actively opposing landscape stewardship is just plain foolish. Alternatively, perhaps these critics are innocent victims in the crossfire of a fight they don’t fully understand, somewhat unaware of their surroundings. It’s the only way I can make sense of it. I’d appreciate any insights you might have on what’s going on here.
I’m currently using WiFi at a gathering on a colleague’s luxurious ranch on Devil’s Gulch Road in upland Colorado. I’ve discussed examples of these interactions and many are aghast. The sense is that amateur GHG enthusiasts and phony-environmentalists are losing their way.
Sabine says
to JCM
Kudos!
It’s unfortunate the phoneys and unhinged extremists are everywhere.
They are on all sides of the global warming ‘argument’.
Sabine says
to JCM
I think you are an excellent communicator and writer. I’d recommend you create a Substack space or similar and share these kinds of issues more broadly. There are many good publishers on the topic on substack already who may help to spread your information. And getting an X twitter account and the alt bluesocial account (where some climate scientists are emigrating) to promote your new articles or data could be useful and effective for you.
Your quality insights, clear communication and knowledge are really wasted here on RC. It truly is an inactive backwater and very much a broken record of rhetoric with a very narrow (myopic) focus and troll-like behaviours from the resident groupies.
imho you deserve much better
JCM says
thanks Sabine. I must admit however, that writing/publishing and academic-style pursuit are not my primary interests. Additionally, I’ll leave social media banter to the cyber pros as I’m not familiar with the most effective tactics. My interests are specifically in applied science, practical implementation, and engaging with communities. Personally I find this to be much more fulfilling.
Piotr says
JCM to his Robin, July 13:
“ To Tomas,
Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. Obviously this directly opposes the bizarre distortions on display by respondents.
The key word here: “extreme”, as in the difference between all non-iced land being a desert and all non-iced land being a swamp – even for such a EXTREME difference (all desert – all swamp), the global T increased only by 8K. The real Earth does not undergo such extreme swings – consequently – the difference in global T for LESS EXTREME cases (“low – high resistance to evaporation”) is about … 1K.
Furthermore – humans can affect only a fraction of that 1K – since human CHANGES to fluxes of H2O are tiny compared to the natural fluxes, and the residence time of water vapour in the atmosphere is measured in DAYS, as opposed to GHGs – where human emissions are much larger compared to the natural fluxes, and the residence time of human perturbation of GHGs is measured in DECADES ,not DAYS.
As a result of these two factors – the current global concentration of CO2 is about 50% above the preindustrial, CH4 200% above preindustrial, while water vapour can be affected by humans in any appreciable way only through warming by GHGs via Clapeyron Clausius equation. Therefore, if you want to reduce warming caused by reduced clouds – you do it by reducing the temperature by reduction of GHGs concentrations. Water cycle is a feedback, not a driver, and as such it amplifies the effects of our action or inaction on GHGs.
To quote you: “Obviously this directly opposes the bizarre distortions on display by respondents.” Specifically:
– respondent JCM: calls the effects of human (direct) changes to evaporation on global T – “mindboggling” and blames world desertification and ecosystems destruction on … science’s “artificial fixation on trace gas”
“ It is truly hard to imagine denying or actively minimizing this due to an artificial fixation on trace gas” (c) JCM
– respondent Kalisz first calculates how much water we’d need to evaporate to cancel out the radiative forcing of ALL GHG gases, then inspired by JCM’s reading of Lague et al. – formulates a “modest proposal” of increasing the global desalination … at least 1000-FOLD, and spreading the produced water over 5mln km2 of Sahara, with the hope that after 100s of years – the scheme may approach 0.3K cooling.
(Conveniently neglects the warming from massive GHG emissions of constructing and running such a scheme for 100s of years)
JCM: “ Piotr and co were totally wrong to imagine that catchment stability is inversely related to climate stability.”
The Piotr you speak of must be living in your brain, JCM, The _real_ Piotr didn’t “imagine” anything of the sort -my argument does not need any relationship, inverse or not, between catchment stability and climate stability, In fact, the word “catchment” DOES NOT APPEAR in any of my posts on the subject. Nor the word “catchment” exists in your source, Lague et al (2023).
I’d suggest less discussion of the figments of your imagination – and more addressing the falsifiable replies of your opponents to your claims. Like those above, and in the many posts before this.
Tomáš Kalisz says
In Re to Piotr, 13 Aug 2024 at 9:37 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823711
Dear Piotr,
It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Water vapour concentration in atmosphere is basically independent from water cycle intensity. Residence time of water vapour in atmosphere is a variable that has an extreme broad range,.. just a few remarks that show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.
Best regards
Tomáš
Piotr says
Tomas Kalisz Aug.14: It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
That’s the problem: your “understanding” ;-) Hint: nobody argued that Lague et al. didn’t use constant GHGs conc.. (Excluding the effect of GHGs was to JCM conflating
the direct effects of evaporation with the effects of GHGs)
TK: “ I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Lague’s comparing an EXTREME and HYPOTHETICAL case of all land covered with deserts, with an EXTEREME and HYPOTHETICAL case of all land being a swamp, SAYS NOTHING about the magnitude of the HUMAN effect on global T via human changes in global evaporation.
So who of us two “ sounds like he has not read Lague 2023 at all >, and has the <b> hutzpah to lecture others based on his own ignorance (inability to understand what he reads) and his intellectual dishonesty (ignoring tens (?) of post where I have already explained to you where your misrepresentation of Lague’s paper lies) ?
TK Residence time of water vapour in atmosphere is a variable that has an extreme broad range
Irrelevant to the discussion at hand: all your “ extreme broad range variability ” gets INTERGATED over the AGW time- (“decades”) and space- (“global”) scales. And when you integrate – the transient/local fluctuations are AVERAGED OUT and therefore of no further consequence. The best example are the results of your Lague et al 2023 – who integrated all those “extreme” local differences to produce a SINGLE average value for all land and another SINGLE average value for all oceans. Which brings us to the reason why we talk about you
And in both cases – these numbers are in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs.
Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
Thus your and JCM narrative trying to minimize the importance of GHGs to AGW, and
trying to dissuade the world from getting off the fossil fuels by implying that we can counter GHGs effects with evaporation geoengineering schemes – remains a denier’s wet dream.
“[opponents] remarks show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.”
and yet you have commented incessantly on Lague et al – even though you the very opposite of “a climate science professional” – you have commented on Lague’s paper in dozens of threads, and used them as a support for your claims – even though have not taken any climate courses, didn’t bother to read any climate textbooks, and even few months ago didn’t understand the differences between fluxes and reservoir size. “ Do as I tell you not as I do”?
Piotr says
** Please ignore the previous version that went off before the final edit.- Piotr
Tomas Kalisz Aug.14: It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.
That’s the problem: your “understanding” ;-) Hint: nobody argued that Lague et al. didn’t use constant GHGs conc.. (Excluding the effect of GHGs was addressed to JCM who has conflated the direct effects of evaporation with the effects of GHGs)
TK: “ I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.
Lague’s compared an EXTREME and HYPOTHETICAL case of all land covered with deserts, with an EXTEREME and HYPOTHETICAL case of all land being a swamp. This SAYS NOTHING about the magnitude of the HUMAN effect on global T via human changes in global evaporation.
So who of us two: “ sounds like he has not read Lague 2023 at all ?
And who has the hutzpah to lecture others based on his own ignorance (inability to understand what he reads) and his intellectual dishonesty (ignoring tens (?) of posts that has shown your misrepresentation of Lague’s paper) ?
TK Residence time of water vapour in atmosphere is a variable that has an extreme broad range
Irrelevant to the discussion at hand: all your “ extreme broad range variability ” gets INTERGATED over the AGW time- (“decades”) and space- (“global”) scales. And when you integrate – the transient/local fluctuations are AVERAGED OUT and, therefore, of no further consequence. An you have already seen it in your own source: Lague et al 2023 integrated all those “extreme” local differences to produce a SINGLE average value for all land and another SINGLE average value for all oceans.
And in both cases – these numbers are in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs. Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
Thus your and JCM narrative trying to minimize the importance of GHGs to AGW, and
trying to dissuade the world from getting off the fossil fuels by implying that we can counter GHGs effects with evaporation geoengineering schemes – remains a denier’s wet dream.
TK: “ [opponents] remarks show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals. ”
writes … Tomas Kalisz, who have posted for months on Lague et al., EVEN THOUGH he has not taken any climate courses, wasn’t interested in reading climate textbooks, even few months ago didn’t understand such basic concepts as the differences between fluxes and reservoir size,
“ Do as I lecture you, not as I do “?
And to make thing better, demands that the top climate scientists in the world explain things to him, when he didn’t bother to do his damn homework. And bitterly complains when they don’t.
Tomáš Kalisz says
In re to Piotr, 15 Aug 2024 at 11:29 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823767
Dear Piotr,
I hope that I already know the relationship between reservoir size (atmosphere volume above a selected surface area multiplied with the average absolute air humidity therein), flux (average annual precipitation over the selected surface area) and residence time (reservoir size divided by flux), I do not understand how you from a short (in global average) water vapour residence time derived your conclusion that the direct effects of anthropogenic changes in evaporation “disappear after days”.
I would rather expect that if we changed e.g. the water availability for evaporation, the respective changes in water cycle intensity and/or air humidity may persist until the water availability for evaporation changes again.
Are you indeed sure that your comparison of residence time of water and CO2 has any predictive value for relative importance of the respective anthropogenic changes for Earth climate?
Greetings
Tomáš
Piotr says
Toams Kalisz: I hope that I already know the relationship between reservoir size (atmosphere volume above a selected surface area multiplied with the average absolute air humidity therein), flux (average annual precipitation over the selected surface area) and residence time (reservoir size divided by flux),
That you can repeat their definitions, does not mean that you understand “the relationship between these three” nor their implications to the schemes you promote here. As is obvious from your next sentence:
TK: “ I do not understand how you from a short (in global average) water vapour residence time derived your conclusion that the direct effects of anthropogenic changes in evaporation “disappear after days” ”
The water vapour residence time of 2-10 days MEANS that if you ADD water vapour to the atmosphere – it will be GONE from there by 2-10days – hence your extra vapor affected the climate only for the same 2-10 days.
As opposed to CO2 where the residence time of our human perturbation is in many DECADES, and therefore removal of GHGs now will continue to affect the climate for DECADES.
So only somebody who has no idea of the MEANING of even such a basic concept as the residence time – would push for diverting the research and AGW mitigation efforts from reduction of GHGs (effects lasting for decades) to increasing evaporation (effects lasting for 2-10 days).
And only somebody completely full of himself would assume that he, must be really really smart if despite knowing next to nothing about climate science – he, Tomas Kalisz, just invented a feasible solution to the AGW that all the climate scientists in the world working on those issues for decades – MISSED!
Tomáš Kalisz says
in Re to Piotr, 20 Aug 2024 at 7:44 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823875
Dear Piotr,
Thank you for confirming that we use the same residence time definition.
As regards your assumption that the average residence time of water vapour (about ca 8-10 days) in Earth atmosphere can imply that any human interference with water cycle (or, more generally, any change in water cycle) has a negligible influence on Earth climate, because its effect must disappear within this short time, I must, however, respectfully disagree.
It is because these interactions do not comprise the water vapour atmospheric concentration only. I think that Lague 2023 is a valuable asset especially because it quite clearly showed that although dramatic changes in water availability for evaporation from the land have small effect on water vapour concentration (because absolute air humidity spreads from the oceans over land even in case that there comes no water vapour from the land at all), the changes in latent heat flux, and, furthermore, the changes in cloudiness, both resulting from this “forcing”, can be very significant.
Lague 2023 suggests that an increase in evaporation from the land can, counter-intuitively, result in a decrease in mean absolute air humidity, due to higher global latent heat flux, higher global cloudiness and lowering of of global mean surface temperature. These effects are not expected to disappear after 10 days, oppositely, they are expected to persist as long as the higher water availability for evaporation from the land persists.
That is why I think that your assertion about negligible influence of changes in land hydrology on global climate, construed from the short residence time of water vapour in Earth atmosphere, may be in fact incorrect and misleading.
Greetings
Tomáš
Piotr says
T. Kalisz.: Dear Piotr, Thank you for confirming that we use the same residence time definition.
Definition of the residence time has not been the subject discussion since that time I had to explain to you the difference between a flux and reservoir size. Here the point is that you parroting the words of the definition without the slightest ideas what it means to your lunatic irrigation schemes.
P: [the residence of WV in atm is in DAYS, as opposed to DECADES the residences time of human perturbation of GHGs. Which means that the effects of human direct changes to evaporation disappear after DAYS, so they are not a viable alternative to reducing GHGs, that would otherwise influence the global T for DECADES.
TK: “I would rather expect that if we changed e.g. the water availability for evaporation, the respective changes in water cycle intensity and/or air humidity may persist until the water availability for evaporation changes again”
No – when after a WEEK – the VW you added to the system is gone – no cloud for cooling – no surplus warming from increased VW concentration the heat reradiated into space of the ground – YOU HAVE TO START again – and week and a week after and a week after. Compared that with removal of CO2 that does not have to be repeated by many DECADES.
Kg per kg water vapour is BY FAR LEAST effective greenhouse gas – its 100-year GPW (Global Warming Potential,) compared to 1 kg of CO2) is = -0.001 to 0.0005.
Which means that to have any measurable effect not only you have repeat evaporating week after week after weak, but each time you have to evaporate MASSIVE amounts of water vapour – which to make it worse – is NOT available on the deserts – the only source being 1000-FOLD increase in desalination – with its astronomic cost and energy-use – hence GHG-generate by the massive desalination and transport over 5 mln km2 over MANY CENTURIES.
In other words if there was an Ig-Nobel Award – for the MOST IDIOTC, MOST COST-INEFFECTIVE, way to mitigate the AGW – you and your JCM would have been the laureates.
Tomáš Kalisz says
In Re to Piotr, 23 AUG 2024 AT 8:45 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823947
Dear Piotr,
I agreed to that if the effect of human interference with water cycle has to be observable, it must persist.
You are therefore correct that in case of an artificial increase of water availability for evaporation from arid areas such as Sahara, it is hardly imaginable without a steady supply of the required water.
Past human interferences with land hydrology, however, might have had rather the opposite effect. There are authors, like Makarieva et al, who suppose that deforestation and/or unsuitable agricultural practices might have impaired rain recycling over entire continents,
Speculations that through a feedback loop, these changes might have finally resulted in substantial decrease of water availability in entire regions thus significantly contribute to their desertification, are difficult to prove or disprove, because it seems that our knowledge regarding past global precipitation and its geographic distribution are still extremely limited.
Furthermore, there seems to be still a knowledge gap with respect to the relationship between water availability for evaporation from land and global climate sensitivity towards other forcings.
It is, however, clear that if above described human activities like land deforestation indeed changed continental water regimes, the respective changes in water availability for evaporation persist. In this sense, your argument based on short mean residence time of water vapour in Earth atmosphere may be completely irrelevant.
For all these reasons, I still think that your claims about negligible influence of human interferences with land hydrology on global climate are too bold.
Greetings
Tomáš
Piotr says
Tomas Kalisz: Aug. 25 “ There are authors, like Makarieva et al, who suppose that deforestation and/or unsuitable agricultural practices might have impaired rain recycling over entire continents”
One could “speculatively suppose might have” ANYTHING. It counts whether one can support quantitively their speculations – here by calculating that significant part of AGW was caused by deforestation. Neither Makarieva, nor you, did.
TK if above described human activities like land deforestation indeed changed continental water regimes, the respective changes in water availability for evaporation persist. In this sense, your argument based on short mean residence time of water vapour in Earth atmosphere may be completely irrelevant.
Neither you nor your Makarieva did quantify the effects of deforestation on global T.
But what you failed I could try with the help of your another source Lague et al 2023:
– EVEN if we assumed that all agricultural land has been created by deforestation, that there is no irrigation of the fields, and the Lague’s 8K difference between all land being swamp, and all land having zero evaporation – the maximum effect would be warming by ~ 1K.
But in REALITY it would be only a tiny fraction of that ~ 1K:
1. we need to reduce the area of the agricultural land by fraction of cropland that hasn’t been created by deforestation (Eurasian Steppe, Prairies, Pampas, Savannas, most of agricultural land in Australia, irrigated semideserts (Central Asia, River Nile etc)
2. neither croplands have zero evaporation, nor many forests have the evaporation of a swampland, hence the actual effect on global T is only a fraction of the max. difference calculated by the difference between a swamp and zero evaporation
3. the reduction in evaporation due conversion to cropland may be compensated by irrigation, used precisely in the places where the evaporation is otherwise limited.
Therefore, instead of 1K warming – we have a fraction, of a fraction of 1K, that may be further offset by the increase in evaporation due to irrigation.
So to borrow your phrase – it is you, Mr. Kalisz, who “ may be completely irrelevant” here.
Tomáš Kalisz says
in Re to Piotr, 26 Aug 2024 at 8:08 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824026
Dear Piotr,
In my opinion, Makarieva et al
https://www.frontiersin.org/journals/forests-and-global-change/articles/10.3389/ffgc.2023.1150191/full
provide, from very different perspective than Lague et al, another hint in the same direction.
I understand their article similarly as Lague 2023 – the way that anthropogenic changes in terrestrial hydrology indeed might have contributed to the observed AGW.
I recommend reading the fulltext, it is also an open access article. If you do so, you will find out that not only Lague but also Makarieva et al in fact tried to provide a quantitative esstimate for this anthropogenic effect:
“Historical deforestation affected about 13% of land area Sl=1.5×108 km2 (or 3.8% of planetary surface SE=5.1×108 km2) (Figure 1). With the global mean latent flux of FL = 80 W m−2, if deforestation has reduced this flux by thirty per cent (ΔFL ~ −0.3FL), this could increase the surface radiation by −0.038ΔFLΔτ ~ 0.9 W m−2 (cf. Figures 3D, E, Δτ = 1) or twice that number (cf. Figures 3D, F, Δτ = 2), Table 1. Given an equilibrium climate sensitivity ε ~ 1 K/(W m−2) (Zelinka et al., 2020), the latter case corresponds to a warming of about two degrees Kelvin (Table 1).”
I do not overemphasize the accuracy of both estimations (by Lague and Makarieva), because it is obvious that quantitatively, they substantially differ from each other. What I see potentially important, however, is the circumstance that despite of very different approach, both estimations qualitatively point in the same direction.
Greetings
Tomáš
Piotr says
Tomáš Kalisz 27 Aug
“Makarieva et al provide, from very different perspective than Lague et al, another hint in the same direction.”
The role of papers in climate science is NOT to provide wishy-washy “speculations” and “hints” on what “ supposedly might have” been the case, but quantitative evaluation of the speculations. Neither you nor your Makarieva delivered it – since neither of you quantified the effects of deforestation on global T.
That’s IN CONTRAST’s with Lague et al. – who provided NUMBERS for the global effects on T of two extreme cases, which then in turn allows us to put QUNATITATIVE constraints on the effects of deforestation on global T.
Which as I have shown, in the post to which your “reply”, to be:
“ a fraction, of a fraction of 1K, that may be further offset by the increase in evaporation due to irrigation ” – for details see my post from Aug.26 you are supposedly replying to.
So, my dear Kalisz, your claim that Makarieva results were “ in the same direction ” as the analysis based on Lague et al – is a LIE,
And so much for your? Makarieva? effects of what “might have impaired rain recycling over entire continents” on global T.
TK: “I recommend reading the fulltext”
says the guy who can’t understand even simple post on RC, not even the implications of his OWN posts …
The onus of proving YOUR claims is not on the reader, but on its author – YOU have find the quotes in Makarieva in which she quantifies the effect of changes in water cycle by deforestation – as being MUCH bigger than “a fraction, of a fraction of 1K globally, that may be further offset by irrigation ” – based on the quantitative results of Lague et al.
Nigelj says
Tomas Kalisz:
“It is my understanding that the models used by Lague 2023 suggested that global water cycle intensity decreased and global water vapour concentration increased in the “desert land” model situation, while concentration of greenhouse gases remained constant.”
This sounds weird. How can the concentration water vapour, a greenhouse gas increase and yet concentration of greenhouse gases remain constant?
“I think that when you continue in using vague phrases like “water vapour can be affected by humans in any appreciable way only through warming by GHGs”, it sounds like you have not read Lague 2023 at all.”
No more vague than your statement: “Residence time of water vapour in atmosphere is a variable that has an extreme broad range”
I have not followed the endless debate between you and Piotr in detail, but his point seems to be that you have this desert land and swamp land scenario and a certain temperature differential and when you look at what humans have done and could practically do to shift earth from one extreme to another it looks like it would fall far short of the calculated temperature differential. His comments are a sort of first approximation but his quantitative reasoning looks good. You havent even provided a first approximation to defend your own argument.
“Residence time of water vapour in atmosphere is a variable that has an extreme broad range”
From the study “The residence time of water vapour in the atmosphere”…”The time water spends in the atmosphere, or WVRT, is a fundamental diagnostic of the climate system. WVRT varies widely, ranging from less than 2 days over the subtropical oceans to more than 10 days at high latitudes, reflecting regional differences in precipitation-generating mechanisms.”
https://www.nature.com/articles/s43017-021-00181-9#:~:text=The%20time%20water%20spends%20in,differences%20in%20precipitation%2Dgenerating%20mechanisms.
Is 2-10 days extremely broad? I dont think so but its hard to define what extremely broad means. However 2 – 10 days does not come even remotely close to the residence time of CO2 in the atmosphere. which is measured in centuries. This is the point Piotr made and its irrefutable.
“just a few remarks that show why I would prefer if the comments on articles like Lague 2023 were published primarily by climate science professionals.”
Yet you are not a climate science professional and you have posted numerous comments on Lague. So you are practicing double standards.
Its a public forum so anyone will comment on anything. Deal with it! I think its best to focus on the content of what people say, and not worry too much about their qualifications.
Tomáš Kalisz says
In re to Nigel, 15 Aug 2024 at 3:57 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823774
Dear Nigel,
To assess if I described the results described in Lague 2023 correctly, you can inspect the full text of this open access article on
https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1/pdf .
As regards the residence time of water vapour in the atmosphere, if we take the simplest definition thereof as the ratio of the annual sum of precipitation over certain area to the average overall amount water comprised in the air column above this area, and assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year. Taking into account that there are desert areas with a significantly lower annual sum of precipitation, you can roughly estimate that water vapour retention time on present Earth may vary in the range from single days to tens of years. I am not sure if comparing this parameter for water and non-condensing gases makes any sense.
As regards Piotr’s calculations of the cumulative effect of forest conversion into cropland by humanity, I offered a much simpler example of conversion of ca 5 million square km of wetland into desert (or vice versa), with a similar direct effect on mean global surface temperature about 0.3 K. I think that a discussion, systematically restricted by Piotr just to a question if such direct effect of 0.3 K is significant or negligible, makes little sense without a broader context which I tried to address e.g. in my post of 4 Aug 2024 at 7:57 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823562 .
As regards the content of my “comments” on Lague in their entirety, I do not think that I apply a double standard. I believe that if you read them, you would rather say that I just asked questions inspired by the article and/or expressed my doubts if bold conclusions derived therefrom by Piotr (in the sense that “human interference with terrestrial water cycle has a negligible influence on Earth climate”) are indeed justified.
I still think that these doubts were not addressed in comments provided by Piotr, at least not the way that would help to resolve them or to clarity that they may be indeed relevant. If they were addressed, I would spare my calls if someone else could perhaps do so.
A specific example: My attempt to suggest that there may still be an open question what is the influence of water availability for evaporation on climate sensitivity – which could influence earth climate significantly even in case that the direct effects thereof were indeed negligible – was simply dismissed by saying “your suspicions and feelings are irrelevant”.
Of course this is also a possible way how to discuss. I just think it is not the most productive one.
Greetings
Tomáš
Barton Paul Levenson says
TK: if we take the simplest definition thereof as the ratio of the annual sum of precipitation over certain area to the average overall amount water comprised in the air column above this area, and assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year.
BPL: You’re assuming no moisture-bearing winds in or out of the area.
The average residence time of water vapor in the atmosphere is 8.9 days.
https://hess.copernicus.org/articles/21/779/2017/hess-21-779-2017.pdf
Kevin McKinney says
Tomas, you should read Nigel’s citation. Your definition is clearly idiosyncratic at best.
And given that it arrives at a radically different value than given in a review article, there’s good reason to think it is completely wrong.
Piotr says
Tomas Kalisz “ I offered a much simpler example of conversion of ca 5 million square km of wetland into desert (or vice versa), with a similar direct effect on mean global surface temperature about 0.3 K.
For some reason you forgot mention that your “simple” scheme would also:
– require increasing the current global desalination ~ 1000-FOLD,
– pumping huge volumes of desalinated water over 1000s of km of pipes to spread it over over 5 mln km2
– have to be maintained for at least THOUSANDS of YEARS to even approach that 0.3K cooling – the 0.3K assumes formation of the swamp vegetation over half of the Sahara. vegetation requires, among other, soil; formation of 1 cm of soil takes ~ 200 years)
– the amount of GHGs emitted to the atmosphere to do the desalination and distribution of the water over THOUSANDS OF YEARS – would cancel most, or even reverse, that 0.3K cooling.
In other words, your modest proposal is to spend trillions of dollars year after year over 1000s of years to achieve …. a miniscule cooling or even a net warming.
With modest proposal like yours – who needs J. Swift?
Tomáš Kalisz says
in Re to Kevin McKinney, 19 Aug 2024 at 12:30 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823848
and Barton Paul Levenson, 19 Aug 2024 at 8:21 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823841
Dear Kevin,
The reference provided by Nigel is very interesting, however, not easy for me as a layman and I will need time to grasp the message (if I will be able to grasp it at all).
Nevertheless, I think that the definition of water vapour residence time which used in my example is in accordance with the reference provided by Barton Paul. Please note the end of the first paragraph in the right column on the first page of this article, which reads:
“All of these examples estimate the global average residence time of atmospheric moisture based on the size of the atmospheric reservoir divided by the incoming or outgoing
flux and as such arrive at estimates in the range of 0.022–0.027 years or 8–10 days.”
I no way disprove this mean value, nor the conclusions made in the more recent article cited by Nigel. I do not think they are in a discrepancy with my example, which does not speak about averages over a range of latitudes but about a more granular view on geographic regions with specific hydrological regimes. The purpose of this example was to show that at regional level, the variability of water vapour residence time is much bigger than the range derived from averaging it globally or over a range of latitudes.
Dear Barton Paul,
Thank you for the reference.
As regards your objection, I think that the absolute humidities about 5 g water in 1 m3 air observed over hot deserts like Sahara have to be indeed explained by long-range water vapour transport.
If I considered that the water vapour above my exemplary desert with annual sum of precipitation 50 mm came solely from local evaporation, then, assuming the residence time about 0.03 year, its mean atmospheric concentration would have been as low as 0.15 g/m3.
In such case, the corresponding mean relative humidity in this region would have been close zero, in discrepancy with mean relative humidities observed in desert regions like Sahara, which are to my best knowledge somewhere in the range 20-30 %.
I therefore still suppose that my example considered the reality of the long-range water vapour transport properly and that the long residence time of water vapour over hot desert regions of Earth is in fact a direct consequence of this long-range transport.
Greetings
Tomáš
Piotr says
Kalisz: if assume absolute air humidity 5 g H2O/m3 air in a desert area with an annual sum of precipitation 50 mm, the retention time may be as long as 1 year.
BPL: You’re assuming no moisture-bearing winds in or out of the area.The average residence time of water vapor in the atmosphere is 8.9 days.
Kalisz is like Trump – makes poorly formulated and different statements, so when questioned he can choose the one that fits the moment.
– in this post, to inflate the residence time of water vapour from days to “1 year” – he “assumed” no horizontal movement of air with moisture
– in another post – his compliments Lague et al. on showing …. the importance of the said horizontal movement or air with moisture from the ocean onto a desert.
By making two opposite assumptions he is bound to be always right … ;-)
knows it – because he was lecturing others for not reading Lague et al who show that even with zero evaporation from land – there is water vapour over it
Tomáš Kalisz says
in Re to JCM, 13 Aug 2024 at 1:34 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823701
Dear JCM,
Welcome back from your vacation.
I am not completely sure yet if Piotr indeed does represent everybody on this website, including the hosts.
It is, however, well possible.
In my reply to him of today, 14 Aug 2024 at 2:59 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823728
I tried to draw a preliminary conclusion from our debate.
Let us see if someone will dissent with Piotr’s view.
Greetings
Tomáš
Piotr says
Tomas Kalisz: “Dear JCM, Welcome back from your vacation.”
What, no flowers?
TK: I am not completely sure yet if Piotr indeed does represent everybody on this website, including the hosts.
What a …weird thing to say, given that I never claimed that I represent anybody but myself, and my arguments rely on logic and facts, not on “representation”. Fighting your strawmen often, Mr. Kalisz?
TK: Let us see if someone will dissent with Piotr’s view.
What for? You have ignored the criticisms of the same claims by others before, so what would be different now?
Tomáš Kalisz says
In Re to Piotr, 14 Aug 2024 at 12:25 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823736
Dear Piotr,
Of course that you write for yourself. I just tried to express my feeling that the majority of discussion participants herein shares your views.
I asked my question if someone’s view perhaps differs from yours because the present question – if others share also the view that my questions can undermine the reputation of climate science – is important for me.
Greetings
Tomáš
Piotr says
Tomas Kalisz: “if others share also the view that my questions can undermine the reputation of climate science ”
To “undermine the reputation of climate science” you would have to know something about the science.
Your capability as an uneducated in it denier are much more limited -because the deniers don’t need to refute the climate science with a better alternative explanations – all they need is to “seed the doubt” and spread it via Internet, where every opinion is equally valid, a post from Gavin has to the general public the same weight, as a post from Tomas Kalisz, JCM, or other Mr. Know it Alls.
And once the doubt has been spread and seeded – it can be used for plausible deniability by the politicians to block action on the GHG reduction and continue trillion dollars subsidies to the fossil fuel interests – if:
– “The science is not settled”;
– “There are major knowledge gaps”
– the science does not want to address them,
– ” it is hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
– human changes of the water cycles have “ mindboggling ” effect on AGW
changes in the water cycle] due to an artificial fixation and overemphasis on the outputs of trace gases (c) JCM
– the climate science is “ artificially fixated and overemphasize the role of trace gases” while resulting in the global desertification
then – let’s not rock the boat until the science is settled, let’s redirect the research and money from GHG mitigation to the non-GHG geoengineering. And in the meantime lets continue the corporate welfare for the fossil fuel industrial complex:
“ Globally, fossil fuel subsidies were $7 trillion or 7.1 percent of GDP in 2022,” (source: IMF)
Even though your role in this is that of a small cog in a machine – it is irrelevant to the ethical evaluation of your actions as an individual – you are what you support. Whether you support it as a paid troll, or more likely, as a “useful idiot” of the fossil fuel interests – does not make much difference. By their fruits you shall know them.
Barton Paul Levenson says
JCM: Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. . . . Obviously this directly opposes the bizarre distortions on display by respondents. Global landscape hydrology is a huge known information gap which is increasingly recognized. When detractors say things like “both of you REFUSE to acknowledge the conclusions” it doesn’t make any sense at all.
BPL: Why don’t you write to Dr. Lague and ask him what he meant?
Piotr says
JCM: “Lague 2023 clarifies specifically in the concluding remarks that “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change by altering atmospheric water vapor and cloud cover”. . . . Obviously this directly opposes the bizarre distortions on display by respondents.
BPL: Why don’t you write to Dr. Lague and ask him what he meant?
Well, it’s her (“Larysa”). But the more important point that the authors are rarely the objective judges of the importance of their own work. ;-) So a more informing question would be
====
what % of Delta T= 8K between the two EXTREMES (all continents a desert minus all continents a swamp) could possibly be attributed to the net (direct) changes in evaporation by humans (e.g. reduction due to deforestation minus increase due to irrigation).
In other words – whether the human ALTERATION of the natural evaporative fluxes is, has indeed a “mindboggling” and is “profound forcing of AGW, and therefore her paper supports JCM attacks on the existing climate models – where he blames “ the planet’s land degradation and loss of native ecologies on the climate models being “ artificially fixated and overemphasizing [ the role of GHGs in global T changes] :
“ UNCCD reports up to 40 % of the planet’s land is degraded and annual net loss of native ecologies continues unabated at >100 million ha / decade. This is a profound forcing to climates and puts our communities at risk. It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis
“ hard to imagine denying or actively minimizing the consequences to real climates due to an artificial fixation and overemphasis on the outputs of trace gases ” (c) JCM
It might be interesting to see whether Dr. Lague agrees with JCM’s use of her name and her work.
Russell Seitz says
BPL : You rang ? Sen the contact info you requested weeks ago.
Barton Paul Levenson says
RS,
I was looking over our long conversation about nuclear winter/autumn five years ago, and I realized I used very intemperate language and even swore at you a couple of times. I’m ashamed now that I acted that way and I would like to apologize. I should apologize, as well, for waiting so long to do this.
JCM says
Thanks BPL. Although I think the meaning of Lague’s remark is only ambiguous to those who want it to be. It simply opens the door for future research. I noticed she is now in partnership with Gordon Bonan who’s career has focused on human disturbance to forest systems specifically. Their next article in press is Reimagining Earth in the Earth System. at Journal of Advances in Modeling Earth Systems (2024).
Human and natural changes to the land is the obvious trajectory of her career, including interesting stuff about continental configuration. These biogeophysical and biogeochemical effects are complementary the early simpler geophysical perspective focused on fluid dynamics and radiative forcing in GCM.
Lague’s specific article here only makes reference to a linear change to evaporative resistance in units s/m. As I previously mentioned long ago, the proportional analysis introduced by Patrick o is slightly misleading because for 1 unit change in resistance has the same response regardless of the initial condition. She clarifies in lecture that other unexplored factors may not be linear, such changes to surface roughness. In other works specific to forests, Bonan is interested in BVOC and aerosol changes related to forest change. Lague’s ET is just piece of the puzzle. Personally I am most interested in soils.
cheers
Piotr says
Re: JCM Aug 15.
Your (JCM’s) saying that Lague’s paper: “ simply opens the door for future research. ” is cop-out AFTER you quoted her statement: “This extreme experiment raises the question of how real-world changes to the land surface (e.g. land use, agriculture) may be contributing to climate change”
In support of your claim about “mindboggling” importance of the human changes in water cycle to AGW, and in support of your blaming the climate models for:
the planet’s land degradation and loss of native ecologies [due to] an artificial fixation and overemphasis on the outputs of trace gases ”. (c) JCM
For THAT – you, or YOUR SOURCES has to answer a question I have already posed to you:
– ” what % of Delta T= 8K from Lague et al 2023 between the two EXTREMES (all continents a desert minus all continents a swamp) could possibly be attributed to the net (direct) changes in evaporation by humans (e.g. reduction due to deforestation minus increase due to irrigation).”
– and to show that the result (= % * 8K) is significantly LARGER than the increase in T caused by the increases GHGs,
“ Simply opens the door for future research. ” doesn’t deliver either.
Tomáš Kalisz says
In Re to Piotr, 18 AUG 2024 AT 8:10 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823833
Dear Piotr,
Your perpetual repetition of your cropland example does not resolve anything, and you already have to know it.
Besides the circumstance that your example is speculatively parametrized and thus prone to endless discussions if this or that arbitrarily set value is really suitable and reflecting reality or not, I am afraid that your arguments suffer from further severe deficiencies:
1) You seem to take the quantitative estimations of Lague 2023 as given, whereas it is quite clear that they can be even lower (in this case supporting your “delta t less than 0.3 K” claim even stronger), but equally well they can be significantly higher, thus making your claim weaker.
2) Even in case that your “delta t” claim was fully justified and strongly supported with undisputable data showing that the direct influence of changes in water availability for evaporation indeed have a negligible influence on global mean surface temperature, I insist in my opinion that your conclusion speaking about “influence on global climate” is an unjustified generalization.
Global climate is not the same as global mean surface temperature, and if something can have an influence on temperature, we have to ask if perhaps its influence on precipitation (amount thereof, and distribution thereof) is also (un)important. Lague 2023 seems to suggest very moderate influence of dramatic changes in water availability for evaporation to precipitation patterns, whereas reality of Earth’s deserts suggests that this influence might be very strong.
3) Moreover, so far we spoke about direct effects only. It still remains, however, completely open if changes in water availability for evaporation can or cannot have very pronounced indirect effects on global climate, through possible influence thereof on climate sensitivity.
For all these reasons, I would be personally quite cautious in drawing bold conclusions like “human interferences with water availability for evaporation have negligible influence on global climate”.
Greetings
Tomáš
Piotr says
T. Kalisz Aug.21 Your perpetual repetition of your cropland example does not resolve anything, and you already have to know it.
That’s because your hero, JCM, as a part of his denier’s agenda “Anything by GHGs” have used Lague et al as a proof of “mindboggling” (JCM) potential of mitigation of GHG by human changes by humans water fluxes, and that “mindboggling potential” presented as a proof of climate science’s “ artificial fixation and overemphasizing [the role] of trace gases”.
To which I just remind him that even the largest human impact on the water cycle agriculture – based on the data of his Lague et al. – produced LAUGHABLE small effect on global T – “ a fraction of a fraction of a 0.3K”
The only OTHER proposal on the table to alter global T via human intervention in the water cycle – was Tomas Kalisz LUNATIC idea of watering Sahara into a swamp by increasing the present global desalination 1000_FOLD and maintaining it for many HUNDREDS/THOUSANDS OF years to even approach 0.3K colling, an effect that is likely to be cancelled by all the emissions of GHGs over the HUNDREDS/THOUSANDS of years of operating your scheme.
JCM says
Every now and then, I feel it’s important to reiterate that I have never claimed any miraculous potential to compensate fossil fuel emissions through landscape stabilization.
I recently realized that this misunderstanding might stem from arbitrarily placing these concepts within a geoengineering framework. However, I strongly disagree with labeling the stabilization of functional ecologies as geoengineering, in the same way that solar radiation management, strategic tree planting for carbon drawdown, or artificial irrigation schemes are classified. The geoengineering perspective overlooks the fact that the loss of ecosystem function has already directly contributed to regional, and potentially global, climate change, in addition to the atmospheric radiative forcing caused by fossil fuel pollution. The forcing and feedback mechanisms at play are distinct from those associated with trace gases. Ecological stabilization is fundamentally different from deploying an engineered compensation scheme because the loss of functional ecosystems is itself a historical forcing.
That being said, ongoing deliberate distortions, misrepresentations, and twisting of words is clearly being done in bad faith regardless of whatever misunderstandings persist. Taking phrases out of context and rearranging them to completely alter the message is, in my opinion, a particularly low tactic. I once again request that participants cease this behavior. If these actions are not intentional but instead stem from deeply ingrained biases, I encourage you to reflect on this. Consider taking into account how the destruction of functional ecosystems might contribute to anomalous hydrological and temperature extremes. This includes, but is not limited to, drainage and channelization of landscapes, chemical biocide application, soil desiccation, loss of biodiversity, and impaired watershed function.
While the most acute erosion to rockflour might occur on a subsidized cash-crop parcel, the effects are present throughout our communities and beyond, ranging from the forested hills to the central valley. We are witnessing a widespread, ongoing, and unrelenting deterioration of landscapes across the vast majority of the Earth.
Tomáš Kalisz says
In Re to Piotr, 23 AUG 2024 AT 7:56 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823946
Dear Piotr,
It appears that you prefer dealing solely with direct effect of changes in water availability for evaporation on global mean temperature.
In this point, I agree to you that the estimates made in Lague 2023 suggest that this direct effect is small. If you are not going to address other points that I have raised, I think we should stop this exchange because it does not bring anything new.
Greetings
Tomáš
Piotr says
JCM 24 Aug 2024 “ Every now and then, I feel it’s important to reiterate that I have never claimed any miraculous potential to compensate fossil fuel emissions through landscape stabilization
Every now and then, I feel it’s important to confront your declarations with your actual words, e.g.:
====
JCM, June 5 “Join me in celebrating world environment day today June 5th 2024! This year focuses on land restoration, halting desertification and building drought resilience under the slogan “Our land. Our future”. UNCCD reports up to 40 percent of the planet’s land is degraded and annual net loss of native ecologies continues unabated at >100 million ha / decade. This is a profound forcing to climates and puts our communities at risk. It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gas and aerosol forced model estimates.”
===
So, HOW ELSE do you explain your contrasting “ profound forcing to climates” by the human alteration to water cycle, with “an artificial fixation and overemphasis” on GHGs, IF NOT that we should therefore DIVERT the attention and money from “trace gas” mitigation toward changes in the water cycle that provide profound forcing to climates” ?
HOW ELSE do you explain your INSISTENCE on calling GHGs “trace gas”, even though
the term is scientifically sloppy – not properly defined (the analytical chemistry’s definition of “trace” is <100 ppm, i.e. well BELOW the CO2 conc.) and open to manipulation (e.g. to imply that "trace gas" may have only "trace" influence).
All of the above fits well with:
– the main denier's narrative " Anything but GHGs”
– the denier’s standard attacks on the credibility of climate science (“an artificial fixation and overemphasis”)
– describing the terrible consequences of heeding the advice of science on reductions to GHGs:
“40 %of the planet’s land degraded” just before: “ It’s hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the outputs of trace gas and aerosol forced model estimates.”
By their fruits, not their declarations about themselves, you shall know them.
Kevin McKinney says
Tomas, you wrote:
Correct, and this is precisely why ARs discuss at chapter length other aspects of climate. Not sure why I have to reiterate this point.
Not sure what the “something” is supposed to be here. But in any case, the interplay of temperature and precipitation is already the subject of considerable study. So I don’t think we “have to ask”; this question has already been asked, and continues to be investigated. In fact, I think there are already some answers. (E.g., AR chapters dealing with precipitation, soil moisture, drought and the like.)
Globally–our concern here–rather than locally? How so?
Just as it remains completely open whether or not there is a chocolate cake orbiting Jupiter. You haven’t answered any of the fundamental questions as to how your proposed “indirect effect” might work in reality.
–How could ‘water availability for evaporation’ possibly change on a global scale possibly change drastically, given that 70% or so of the planet is ocean, and that despite humanity’s proven ability to degrade ecosystems there are very real practical limits on our ability to fundamentally transform hydrology on the remaining 30%?
–If you propose, as you seem to, that such transformation is presently altering the climate–again, our concern on this site–then where is the evidence? We have been monitoring and studying atmospheric water vapor, in part because we know it’s an important radiative feedback. Is there one single study out there presenting evidence that the rise in absolute humidity is causing observed warming, rather than (as we know from solidly-established theory should be the case) being caused by that warming?
–If you provided a mechanism by which a “possible influence on climate sensitivity” could exist on this planet, I missed it. It’s clear that you have an *expectation* that such an effect should exist, but it’s unclear to me, at least, why that would be. It’s particularly unclear to me why such an effect might be *larger* than the “direct effect.”
(In this respect, I’m returning to my old thought experiment about Arrakis, Frank Herbert’s implausible but enticing imaginary desert world. Clearly–and contrary to my initial thoughts–climate sensitivity on Arrakis should be low, because important feedbacks that exist on Earth are extremely limited on Arrakis. There’s not much water vapor feedback because there’s very little water anywhere on the surface; there is no ice to melt and thereby change albedo; and there’s very little vegetation to affect albedo, either. (That’s the most implausible thing about Arrakis, IMO; where’s the primary production to support those giant sandworms?) So there, doubling CO2 would not increase temperature much beyond the direct radiative effect. But there’s no way–thank God!–to turn Earth into Arrakis, short of exporting most of our water off-world. We aren’t limited by the availability of water; and in fact, the sheer abundance of it on a global scale makes it very challenging to explain why local anthropogenic changes in water availability wouldn’t effectively be swamped by the global warming-driven increase in specific humidity.)
Tomáš Kalisz says
in Re to Kevin McKinney, 26 Aug 2024 at 9:58 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824009
Hallo Kevin,
Many thanks for your kind feedback.
I will start with your Arrakis counter-example.
I am not sure if you noted that the disputed article Lague 2023
(open access under https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1/pdf ) suggests that an increase in water availability for evaporation may in fact DECREASE the mean global temperature and global mean absolute humidity, while the global latent heat flux increases. This is why I asked if the generally accepted view that “water vapour feedback” must any time augment GHG forcing is indeed as general as assumed. Are you sure that the magnitude of this feedback (and, possibly, also its sign) is/are independent from water availability for evaporation?
In view of Lague 2023 who provided an opposite estimation than previous discussions on this website (wherein majority of participants asserted that improving land hydrology / intensifying water cycle by providing more water for evaporation from the land must warm the climate (“because of water vapour feedback”)), I can well imagine that the present “water vapour feedback rule” was derived for the present Earth with its present level of soil humidity, terrestrial vegetation and precipitation distribution, and nobody has ever asked how this “rule” looked like for the Earth 200, 500, 1000, 2000 and 5000 years ago.
Maybe that the results achieved by Lague 2023 came from peculiarities of her climate model – that is why I am curious how her experiment would have looked like using other models. Nevertheless, if her results indeed suggest that higher water availability for evaporation in fact DECREASES global mean surface temperature, then I think that my suggestion to look if good water availability for evaporation might perhaps rather stabilize the climate against other forcings than destabilize it (as generally assumed on teh basis of the “water vapour feedback” estimated for present Earth) may be more relevant than a suggestion to investigate if there is a chocolate cake on Jupiter orbit.
I think so because results of Lague 2023 suggest that even though we have a planet with 70 % ocean, it may not be a guarantee against continental desertification. I can well imagine that we could arrive at hot continents with lot of water vapour on a clear sky thereabove, as described in Lagues “desert land” scenario. And, contrary to the results achieved by Lague 2023 which do not suggest any dramatic change in precipitation, I am afraid that the situation of “continental heat islands” might in fact result in a significant decrease of terrestrial precipitation, and in real desertification of entire continents.
That is why I share JCM’s concerns that by poor agricultural practices and further human activities, causing soil degradation, we may start a feedback loop that can bring us dangerously close to a such Arrakis-Earth.
Greetings
Tomáš
Piotr says
Tomas Kalisz: “It appears that you prefer dealing solely with direct effect of changes in water availability for evaporation on global mean temperature.”
What are you trying to say? What are these … “ indirect effects” which are NOT small, but I for some, presumably nefarious reason, try to avoid discussing?
And why do you imply that these “indirect effects” – have NOT been ALREADY
accounted for in Lague’s by using quite a complex climate model?
After all, it was your guru JCM who brought and promoted the Lague’s paper, while you used it as proof to that your stupid Sahara irrigation schemes have indeed merit?
Aren’t you trying to snatch victory from the jaws of the defeat – by portraying my holding JCM and you to account for your claims, as … “insisting” on talking about things nobody discussed here. And trying to make virtue out of your attempt to change the original subject of the discussion, under the threat of you proudly walking away?
TK If you are not going to address other points that I have raised, I think we should stop this exchange because it does not bring anything new.
When the going gets tough, the tough get going ? ;-)
Piotr says
Tomas: Global climate is not the same as global mean surface temperature…
Kevin: “ Correct, and this is precisely why ARs discuss at chapter length other aspects of climate. Not sure why I have to reiterate this point.”
Because the “anything but GHGs” deniers, having failed to prove that humans can compensate for the entire, or at least substantial part of, warming by the GHGs by increasing evaporation, change the subject by lecturing opponents that
“ Global climate is not the same as global mean surface temperature“.
That sentence has also another undertone – it detracts the attention from the fact that most of the global climate change is driven by AGW (global increase in T), and most of the AGW is driven by increased GHGs. There the most feasible, the most long-term, and the most cost-effective to mitigate global climate change – is to mitigate GHGs.
Which is anathema to the deniers, minimize the role of GHFs by saying: it is “only 0.04%” of atmosphere, or by calling them a “trace gas” (with the implication that a “trace” gas must have only a “trace” influence), and who blame global desertification and destruction of ecosystems on the climate science’s “ artificial fixation and overemphasis” on the role of GHGs. As our JCM put it:
“ hard to imagine denying or actively minimizing the consequences to realclimates due to an artificial fixation and overemphasis on the [role of “trace gases”] “
Tomáš Kalisz says
In Re to Kevin McKinney, 26 AUG 2024 AT 9:58 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824009 ,
part 2.
Dear Kevin,
The next point of you feedback I would like to address are your questions about the mechanism of the hypothetical indirect effect of water availability for evaporation from the land, which, as I suggested, might consist in dependency of climate sensitivity towards other forcings to this parameter (i.e., water availability for evaporation).
In the previous part of my reply, I tried to show that Lague 2023 can be understood as a hint that do called water “vapour feedback” and “cloud feedback” may be much more complex mechanisms than considered so far, and that they may both depend on water availability for evaporation from the land. If you have not read Lague 2023 yet, I recommend to do so. It could make my explanations easier.
The above mentioned hint arises in my opinion particularly from comparison of Lague 2023 with another scenario studied previously using another model which included water vapour and latent heat flux only but not clouds. I think that this comparison justifies my question if the “cloud response” to GHG forcing, now considered as a positive feedback enhancing the GHG effect, must be really the same in other Earth configurations. To avoid recycling the argument that we cannot water present deserts, let us just look back. Are we sure that the clod feedback to GHG forcing was the same (as today) 200 years ago, 500 years ago, 1000 years ago or 2000 years ago, when continental hydrology possibly was quite different from its current state?
As regards my objection that quantitative estimations of Lague 2023 should be taken cautiously, because even her present model may not reproduce real precipitation patterns well: I took these patterns from the global perspective of precipitation partition between land and ocean. If Lague 2023 suggests that eater availability for evaporation from the land may, by combined feedbacks from latent heat flux, from the change in water vapour GH effect, and from the change in clouds, influence the global mean surface temperature, I think our primary concern should be the question if (and if so, how much) it can influence also this land-ocean precipitation partition. And, because precipitation can definitely play very important role in water availability for evaporation, if there can be a threat of negative feedback loop, by which anthropogenic changes in continental hydrology might cause desertification of originally humid and habitable regions.
The reason, why we should ask if water availability for evaporation can influence climate sensitivity towards other forcings, is in my opinion simple: If there are two or more identified forcings, wherein each of them may influence Earth climate alone, we should ask how the act in mutual interplay. And, from the historical perspective, as well as for the sake of shaping climate policies properly, I believe that asking my question if anthropogenic changes in continental hydrology perhaps might have prepared the stage for present GHG global warming, may be justified too.
Best regards
Tomáš
JCM says
Very interesting, Piotr.
I’ve seen this meme “anything but GHG”. To clarify, my focus is on the importance of landscape stabilization, not just any arbitrary issue. Climate is just one aspect of the multiple co-benefits.
This contrasts with those ideologically opposed to the notion of human interference with Earth systems, as they try to find any excuse to avoid acknowledging the required remediation. Perhaps they feel humanity is too insignificant or that natural factors dominate. Whatever the case might be, obviously this is not my view at all. If you continue to associate me with denialists, it’s evident that you’re either not paying attention or deliberately misunderstanding. Are you aware of this?
No amount of effort to create a toxic or hostile atmosphere will push me away. You serve as a prime example of the fixation I mentioned. It is a serious societal issue and is widespread among governance boards, committees, and teaching at all levels. Although well-intentioned and passionate, many self-proclaimed environmentalists operate with a narrow, half-baked perspective, fueled by a strong sense of personal virtue and confidence. Our interaction is providing me with deeper insights into how this bias functions, the extent of the knowledge gaps, and the tactics used to enforce these views. I find this particularly valuable, as you seem to be a remarkable textbook example.
If additional funds are needed for monitoring and research to better formulate the realities outside, and improve both teaching and policy advice, then it should be sought immediately. That should be academic. Many thousands are involved in community conservation initiatives ongoing, but the grass-roots is no match for the scale of the issue. The distorted perspective you have chosen to enforce is unfortunately common nowadays, and in my opinion, it’s extremely counterproductive to our shared goal of Earth system stabilization.
Rediscovering landscapes does not undermine the validity of policy advice related to the CO2-enhanced greenhouse effect. Your argument exemplifies the classic zero-sum fallacy. I suspect your disregard for significant human impacts stems from the belief that acknowledging the profound deterioration of landscapes is inconvenient and much more challenging to quantify than the direct radiative forcing from fossil fuel emissions. No amount of hand-waving or speculative quantification schemes embedded in extreme ideological rhetoric will convince me otherwise. I think this should be obvious.
Piotr says
JCM 27 Aug Very interesting, Piotr.
I doubt the sincerity of this: your very interest … completely evaporated before my proof how “anything but GHGs” applies to you. No wonder that you think that it may apply only to …. others:
JCM: “ I’ve seen this meme “anything but GHGs” .
As for the rest of your production – I am not interested in your declarations about yourself nor your opinions about others – by their fruits you shall know them – whether “ anything but GHG ” applies to you or not – can be falsifiable tested using your own words and logic. Which I have done in my “very interesting” post:
=== Piotr Aug.26: =========
“So, HOW ELSE do you explain your CONTRASTING “profound forcing to climates ” by the human alteration tof water cycle, WITH “ an artificial fixation and overemphasis” on GHGs?
How else, if not “ Anything (here: the water cycle) but GHGs“?
HOW ELSE do you explain your INSISTENCE on calling GHGs “trace gas”, even though you were shown that the term is scientifically sloppy – not properly defined (the analytical chemistry’s definition of “trace” is <100 ppm, i.e. well BELOW the CO2 conc.) and open to manipulation (implying that "trace gas" may have only "trace" influence).
========
" I’ve seen this meme “anything but GHG” , eh?
Tomáš Kalisz says
In Re to Kevin McKinney, 26 Aug 2024 at 9:58 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824009
Dear Kevin,
In my replies of 26 Aug 2024 at 3:29 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824018
and of 27 Aug 2024 at 2:26 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824034 ,
I tried to explain why I think that so called “water vapour feedback” and “cloud feedback” may not be fixed parameters but rather functions of the actual Earth configuration, in which values of some important variables, e.g. the water availability for evaporation from land (studied as a climate forcing perhaps for the first time in Lague 2023), may change quickly and may be also substantially influenced by human activities.
If these feedbacks are in fact functions depending among other variables also on water availability for evaporation, then also climate sensitivvity towards concentration of non-condensing GHG may depend on water availability for evaporation.
I have not noted any reaction from you yet, so I would like to ask if my explanations were understandable and if you are satisfied therewith.
Thank you in advance and greetings
Tomáš
Piotr says
Tomas Kalisz Aug. 30: “If these feedbacks are in fact functions depending among other variables also on water availability for evaporation, then also climate sensitivvity towards concentration of non-condensing GHG may depend on water availability for evaporation.
Because as it has been explained to you MANY TIMES ALREADY – humans CAN’T CHANGE your “water availability” ENOUGH to make a difference. If they could – changes in water cycle would have been a forcing, not a feedback.
And therefore to mitigate AGW – we need to reduce the FORCING – GHGs, and the effect of GHG reductions will be amplified by the changes in water cycle resulting from changes in GHG forcing.
Kevin McKinney says
Tomas said:
I thought I’d looked at it, but it appears to be a different Lague opus than the one I had read earlier, so thanks for linking. Continuing:
Yes, the view is practically universal. That is because water vapor is, as has been well-known since 1860, a powerful GHG, and because warmer air can sustain more water vapor. More water vapor in the atmosphere cannot cool; and more warming will always enable higher potential specific humidity.
No, of course not. As the Arrakis discussion should have made plain, one can imagine (and Frank Herbert did imagine, more or less) a situation in which water constraint held the water vapor feedback to a very low value. What I question is whether there is any plausible scenario under which such a situation could arise on this planet. More on that later.
However, in the meantime I note that you seem to be suffering from a confusion. Your remarks seem to indicate that you think Lague (2023) somehow undercuts the general view of the water vapor feedback. In fact, the paper completely supports that view.
Here’s how it works in Lague.
1) They artificially constrain surface hydrology in the model. It takes pretty heroic parameters to do so:
Unrealistic, of course, but this is a sophisticated ‘thought experiment’, and doesn’t need to be realistic.
2) They then run the model for 20 virtual years of ‘spin-up,’ and examine the steady state climates that result in each case.
Those results can be seen in their Figure 1. And what do the top panels of that figure show?
Desertland: water vapor increases because atmospheric residence times increase ~50%, due to reduced water retention on land, increased terrestrial temperatures, and those comparatively cloud-free skies you mentioned. As atmospheric water vapor increases, so does temperature: by about 2.5 C over land, but more than 3 C over the ocean. (The opposite happens for Swampland.)
So, what we have is a great demonstration of precisely the water vapor feedback: more water vapor in the atmosphere means more warming. So, no challenge in Lague (2023) to the water vapor feedback. On the contrary, their results rely on that phenomenon.
So, what about your “fear”? Specifically, that:
Well, we’re already achieving something of the first effect by radiative forcing: while precipitation patterns are complex, and trends can be either positive or negative in different locations, we certainly do seem to be seeing a robust intensification of the hydrological cycle–both more intense precipitation, and enhanced evaporation.
However, with regard to the second concern you express, why would you expect that anything we could or will do could approach the state of the terrestrial surface prescribed in Lague? You seem to suggest, without quite saying, that you think some sort of runaway feedback process leading to that result could be possible. But what might that process be? I can’t imagine one, to speak only for myself. Yes, we can make city surfaces largely impermeable, fill or drain wetlands, and channelize rivers, and none of that is hydrologically good. But it doesn’t create Desertland–or Arrakis–on a continental scale, and it doesn’t by itself propagate. I really think you can relax a bit about land use, or at least the global magnitude of its effects, and perhaps worry a bit more about the radiative forcing issue, which is what really seems to be driving change today.
David says
Kevin, your 30 Aug 2:52 pm reply to Tomáš was excellent.
JCM says
“Yes, we can make city surfaces largely impermeable, fill or drain wetlands, and channelize rivers, and none of that is hydrologically good.”
precisely. Today, landscapes are impaired 40% compared to nature.
Repeated arguments by assertion which place humanity as insignificant demonstrate nothing. Those who make such claims might believe they’re presenting a real argument, but they actually offer nothing.
In reality, CMIP6 has no relation to ERA5L, lapse rate, nor TOA SW and LW observation whatsoever. They do not match at all.
No amount of total nonsense assertion provides any value on these pages whatsoever. Extreme desiccation of landscape warms climates, enhances SW absorption, and intensifies warming even more through WV feedbacks. Are y’all even being serious? It’s insane.
Tomáš Kalisz says
In Re to Kevin McKinney, 30 Aug 2024 at 2:52 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824170
Hallo Kevin,
Thank you very much for your fast reply.
Unfortunately, I do not understand your interpretation of the Figure 1 in the cited article.
a) You speak about water vapour increase, however, Figures 1c and 1d show latent heat flux development of the tested models in time. Could you clarify?
b) You ascribe the course of the depicted time curves to the water vapour feedback, although there is no such commentary accompanying Fig. 1. The discussion of results provided by authors is, however, based mostly on results shown in Fidures 3 to 9, and seems to give a more complex picture, I think.
c) Figures 3 to 9 depict differences between swamp land and desert land. I have not noted any other reference system throughout the article. Could you specify where you found the information that in the desert land, water vapour concentration increased commensurately to the water vapour residence time increase which is about 50 %? What was the baseline for this estimation?
Thank you in advance and greetings
Tomáš
Tomáš Kalisz says
in Re to JCM, 30 Aug 2024 at 11:46 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824195
Dear JCM,
I think that I understand the view defended by our opponents:
There is hardly any reliable evidence that human activities during anthropocene led to continental desiccation. Although there may be hints from your practical observations of nature, it appears that there are no reliable precipitation records longer than ca 100 years, nor proxy data that could replace them.
Furthermore, it appears that there are no studies yet that tried to find out by computational modelling if (and if so, how) precipitation distribution between land and ocean could have changed as a result of human activities in the preindustrial era.
I am afraid that we have to wait and hope that such methods and/or studies emerge soon. Until it happens, our concerns that anthropogenic interferences with terrestrial hydrology might have contributed to climate changes observed during anthropocene, including the industrial era, will be taken as mere unsupported speculations.
Greetings
Tomáš
JCM says
Tomas,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824212
in this context – degradation, desiccation, desertification, destruction, depletion of natural capital, erosion, or whatever you prefer – this represents the capacity for ecologies to maintain consistent moisture levels.
https://www.researchgate.net/profile/Rahul-Adhikary/publication/343586418/figure/fig1/AS:930231787466754@1598795949631/Global-soil-degradation-map-Source-UNEP-International-Soil-Reference-and-Information_W640.jpg
This is a known issue of global concern.
Although monitoring is extremely scarce and diminishing, climate science offers the opportunity to deduce these effects through its focus on the atmosphere. One approach is to critically examine and compare CMIP, which primarily emphasizes atmospheric radiative forcing and fluid Earth dynamics, against other sources of information and intermodel consistency.
Recall, climate science is no longer a study of the physics of the atmosphere and oceans, but also the ecology of Earth. This is the promise of Earth system science: to transcend disciplines to enable study of the interacting physics, chemistry, and biology of the planet. There is a real concern that trace gas enthusiasts will try to define the ecology of the Earth system by monopolizing so-called Earth System models.
On model consistency –
terrestrial latent heat flux varies widely across CMIP ESMs, from 35 to 65 W m-2. This significant variation suggests that the ensemble is ill-suited to detect perturbations on the order of 2-4 W m-2. Nevertheless, CMIP is often cited as evidence that large-scale land degradation has minimal biogeophysical impact on climates.
Furthermore, the change in carbon cycling through land is not known better than a range of zero (0) GtC to over 300 GtC in the recent decades across ESMs. Since changes in terrestrial organic carbon are closely linked to moisture stability, it’s almost impossible to draw meaningful conclusions about the impact of land degradation based on CMIP information. Yet this is often done.
Comparing to other information –
as previously discussed, reanalysis products deduce a decrease of ET over the recent decades according to the rigid requirements of simulating atmospheric states. In contrast, CMIP suspects a relentless increase of ET through it’s unconstrained scheme. Given that continents are inherently moisture-limited – a critical factor in their faster warming rate compared to oceans – a fair bit of caution should be used when drawing conclusions using the products of ESMs. Remember, a healthy soil is the wilderness beneath our feet. ESMs have nothing at all to say about that.
Additionally, in a paper you previously shared, it was demonstrated how the lapse rate effect is changing with the incorrect sign in CMIP compared to observed reality. Other works, including Schmidt’s 2023 CERESMIP-related paper, highlight significant discrepancies at the top of the atmosphere (TOA), particularly the unusual decrease in shortwave radiation (SW-out). Today, the Earth’s energy imbalance (EEI) is deviating outside almost all CMIP members and scenarios.
It’s worthwhile to re-consider the ecological aspects of ESMs when a wide variety indicators each suggest similar biases and unknowns related to biogeophysical effects. This input, supported by a variety of literature over many threads, goes well beyond mere assertions.
cheers
Barton Paul Levenson says
TK: , our concerns that anthropogenic interferences with terrestrial hydrology might have contributed to climate changes observed during anthropocene, including the industrial era, will be taken as mere unsupported speculations.
BPL: Climate scientists found decades ago that land use was important to global warming. It is, however, a minor effect compared to that of greenhouse gases. The idea that it is being ignored is not true; please read the IPCC reports.
Secular Animist says
We live in The Age Of Idiot Billionaires.
https://www.theguardian.com/environment/article/2024/aug/13/trump-musk-x-climate
Sabine says
to Secular Animist
While the 1920s the 1950s and the 1970s and 1980s were the Age of Idiot Millionaires.
You think politics and the media wasn’t manipulated and BS back then?
The people may have changed, the issues might appear a little different, but nothing has changed here. The elites of America have been extreme belligerents and a dire threat to the world and humanity for well over 100 years already. Be they a Howard Hughes type or a news / media owner or a funder of elected officials. The Climate issue is the least of your problems in America. One of a hundred symptoms that are now out of control and impacting the entire world negatively.
Myopia affects people in both time and place.
Piotr says
Sabine: “ While the 1920s the 1950s and the 1970s and 1980s were the Age of Idiot Millionaires”
Equivalence fallacy. First, in the 1920s-1950s even science didn’t know much about AGW.
Even 1970s-1980s both scientific understanding and public awareness of the AGW are nowhere those today.
Second, the Idiot Millionaires of the 1970s-80s, held less money and therefore less power, than the todays Idiot Billionaires:
– ” the share of wealth held by the top 1 % from 30 % in 1989 to 39 % in 2016, while the share held by the bottom 90% fell from 33 %to 23 %.”
– “the gap between the richest and the poorest in the U.S. more than doubled between 1982 and 2016.”
So no – it’s not the same.
Secular Animist says
With all due respect your reply is boilerplate rhetoric devoid of any actual content, beginning with telling me what I think, and concluding with a generic insult that has exactly nothing to do with anything I have ever written or posted here. It’s a textbook example of pointless trolling.
Susan Anderson says
Thank you, precisely correct.
Axe grinding, hypocritical intolerance all too often to the fore, as finding people to blame is so much easier than doing something real to make things better.
We have one job, to do the best we can with what we are given. [me: guilty as charged]
Piotr says
Secular Animist to Sabine: “ your reply is boilerplate rhetoric devoid of any actual content, beginning with telling me what I think, and concluding with a generic insult that has exactly nothing to do with anything I have ever written or posted here”
Precisely. And quite representative of the “fundamentalists” here – Sabine, Ned Kelly, and to an extent – Geoff Miell or Killian:
1. despite little or no background in climate science, or because of that – are full of contempt toward climate science and scientists (Sabine: “none of the [Science and Scientists] should be trusted or believed “)
2. the reason for that – if the top scientists in the world failed to see what I, a lay person, did, then I must be really, really, smart.
3. they may use a scientist (say, Hansen) but only if they can cherry-pick their words to present as the confirmation of their narrative (“I have been telling you that for years, but you never listen“)
4, they are fundamentalists: either you are with them or against the truth
5. they are maximalists – it’s “all or nothing”; for them “the good is the enemy of [their] perfect”
6. by setting the goal impossibly high (nothing short of a complete change of the current social structure and economy, and altering human nature) they assure failure by breeding resignation and apathy: “since there is no way to get there – I may just as well give up, enjoy things while I can, and “After us – Deluge!”.
7. because of that, they often end up in bed with … deniers – because their results are the same – the apathy towards getting away from the fossil fuels
8. “ Les extrèmes touchant – while she has a seething contempt toward scientists “(none of the [Science and Scientists] should be trusted or believed“) Sabine goes all gaga over our (“anything but GHGs”) denier, JCM:
JCM blames “ the planet’s land degradation and loss of native ecologies” on “ artificial fixation and overemphasizing [the role of GHGs in global T changes]”
Sabine enchanted: – “JCM , What you say is great to hear and it has the ring of truth.
– To JCM. I think you are an excellent communicator and writer. Your quality insights, clear communication and knowledge are really wasted here on RC.
and fiercely protective:
To JCM: Kudos! It’s unfortunate the phoneys and unhinged extremists are everywhere.
-+ Imho you deserve much better. t”
And their ignorance walks hand in hand with their arrogant conviction of being right even about things they know nothing about:
Sabine “ fair and targeted rational legislation and regulation within a Socialist market economy such as operates in China and Russia where the People come first ”
The tens of millions of the “People” who perished in “the People come first” Soviet Union and Communist China, might beg to differ with Sabine and her glorification of their killers.
Mal Adapted says
Piotr:
I just want to make sure you know that it was the video posted by Sabine Hossenfelder, who commented only once, that’s the source of “none of the [Science and Scientists] should be trusted or believed” quote by multi-posting, singly-named Sabine. I vehemently agree with your comment otherwise.
I, for one, think Dr. Hossenfelder is a skillful but problematic science communicator. With a career as a physicist, she’s uncommonly capable of understanding the physical science behind the consensus of climate-focussed scientists for rapid anthropogenic global warming. I get that she’s convinced by the data that the upward trend of GMST has departed from the more linear slope of the late 20th century, which means the ramifying impacts of warming are ahead of earlier projections. Yet her claim not to trust or believe unspecified scientists is disingenuous, because she stands on the shoulders of giants in her own discipline. Her warnings sound a little paranoid, and are forthrightly arrogant. [G]get back to Logic and the actual Data is all well and good, but Google Galileos rarely have the training and discipline to distinguish truth from deliberate deception, and are all too easily led astray by specious denialism! This is where scientific metaliteracy really makes a difference.
Her video isn’t denialism, to be sure. Her claim not to trust scientists doesn’t mean she thinks they’re exaggerating climate change for some mysterious agenda. She does trust the 200-year history of accumulating, verifiable evidence supporting the scientific consensus that global warming is happening and it’s anthropogenic. But she’s frustrated with scientific reticence and the principle of least drama, because she thinks climate experts should be speaking to decision makers and the public with greater urgency than they have been. I, for one, believe the principle of least drama is central to sustaining science’s epistemic authority, and the whole scientific profession loses by this professional scientist’s glib distrust. And while her suggestion that some scientists are motivated by the quest for grant money may seem reasonable to laypeople, she omits the fact that the majority of the scientists contributing to the consensus can just as easily do research without political consequences. Then there’s her implied false equivalency with denialists directly supported by carbon capital. Pretty freakin’ outrageous, really!.
IMHO anthropogenic climate change is already sufficiently urgent that scientists shouting greater alarm isn’t going to bring many voters along sooner. Dr. Hossenfelder is entitled to her dramatic opinion, and I think she’s pretty sly with the confident alarmism in her videos, but I speak only for myself.
Paul Pukite (@whut) says
Sabine H is good friends with Tim Palmer, he the Oxford climate physicist who recently published a book on the science of uncertainty called “The Primacy of Doubt”. Palmer is heavy into chaos, which is not a great prospect for prediction, but also associated with ECMWF . Haven’t read the book yet, but perusing it, he has some odd ideas on scientific computing — a la errors in numerics due to low-power quiescent-point digital circuitry that may help with climate simulations that he says can consume “10 of megawatts” of power per supercomputer. That gets to my comment up in the thread (search for “100 MEGA watts of power”). Yet, bizarre that he thinks errors in digital computers are benign, and that he doesn’t comprehend that there are parity checks, etc that nip the errors in the bud in any case. Could look into fuzzy logic instead, or NN even.
Desperately need a breakthrough here as throwing more computing cycles at a problem similar to climate dynamics rarely solves anything. I should rewatch the YouTube video of Tim and Sabine discussing climate science topics. Perhaps her outlook is swayed by Tim Palmer’s views.
Susan Anderson says
Mal A (and others) Due to layering, I can’t reply directly.
Please note the ‘sabine’ here is not Sabine Hossenfelder. SH is a skilled communicator whose perspective, while it can be a mite (only a mite) annoying, never departs far from evidence and real science. In fact, she can be quite good, though when she wades into climate science she doesn’t quite get how engaged and distracting the verbal wars about climate can be, and how hard people like our hosts have worked to dispel the fog of ignorance; her efforts come across as more naive than wrong.
The rest of you have produced reams and reams of argument which make it nearly impossible to find the nuggets of value amongst all the dross.
Piotr says
Mal – “ I just want to make sure you know that it was the video posted by Sabine Hossenfelder,
Yes, I know. This is why I was directing my 8 points to “our” Sabine – if you promote somebody’s else claims, then they represent your views, as well as those of the author.
Some of these points obviously do not apply to Sabine H. – obviously she is not attacking science from the position of ignorance (pp. 1-3), I don’t know whether she went all gaga over a specific denier, the way our Sabine went over JCM (so no p. 8 either) – nor she is responsible for our Sabine’s that the Communism in Russia and China, responsible for killing 10s of millions of people, are systems “where the People come first ”
That said Sabine H. “none of the [Science and Scientists] should be trusted or believed” combined with her use of half-truth and false equivalency between scientists and the deniers – suggest that p.4-7 do apply to her too:
==
4, they are fundamentalists: either you are with them or against the truth
5. they are maximalists – it’s “all or nothing”; for them “the good is the enemy of [their] perfect”
6. by setting the goal impossibly high (nothing short of a complete change of the current social structure and economy, and altering human nature) they assure failure by breeding resignation and apathy: “since there is no way to get there – I may just as well give up, enjoy things while I can, and “After us – Deluge!”.
7. because of that, they often end up in bed with … deniers – because their results are the same – the apathy towards getting away from the fossil fuels
====
Mal: Her video isn’t denialism, to be sure
That’s what my pp. 4-7 are about – you don’t have to set out to write a denialist piece to have your opinions help the denialists. The road to hell is paved with good intentions.
Mal: And while her suggestion that some scientists are motivated by the quest for grant money may seem reasonable to laypeople, she omits the fact that the majority of the scientists contributing to the consensus can just as easily do research without political consequences. Then there’s her implied false equivalency with denialists directly supported by carbon capital
This argument is straight from the denier’s writing guidelines – and you pointed to some of the problems – I would add that in most countries the research in government institutions is not funded from external grants, in fact – if anything, during Trump administration or in Russia – Gavin’s position would have been much more secure if he were denying the human cause of climate change.
Furthermore, if follw Sabine H. in her claim that scientists are corrupt – then they must be also idiots for going after pennies from the stingy government coffers, instead for billions available from the fossil fuel industrial complex: if Gavin could convincingly argue that the increase in GHGs is not the main cause of the climate change oil multinationals, Russia and Saudi Arabia would pay him his weight in gold – what’s $ 8 mln (assuming conservatively 100 kg of Gavin) reward compared to the TRILLIONS of dollars in oil profits on the line – you couldn’t dream of a better return on investment.
Sp much for the implied equivalency of climate scientists with the deniers funded by the fossil fuel interests and/or petro-states.
—
P.S. I wonder – has Sabine Hossenfelder included herself among the “none of the [Science and Scientists] should be trusted or believed “ – or the insinuation that scientist betray their ethics and instead prostitute themselves for grant money – applies only to OTHERS?
Mal Adapted says
Piotr:
Snort! What about that, Gavin? I am ROTFLMAO!
Escobar says
Whatever you do, do not watch or listen to what Sabine says. 10 minutes is far too much a waste of your precious time when it’s far better spent attacking climate denying tilting windmills and making it all up as you go. Trump Speak seems to have taken over the whole climate science community here where Facts Data Reason and Logic no longer are needed.
Do a Trump and say whatever pops into your head instead. Weird. The end times are definitely upon us – the people going mad was one of the signs apparently
How I lost trust in scientists
Sabine Hossenfelder
https://www.youtube.com/watch?v=gMOjD_Lt8qY
And definitely do not watch to the end. She is clearly an ‘evil climate science denier shill paid for by the fossil fuels industry and the UK GWPF. I think you should all report her to YouTube and get her Cancelled forthwith. The Biden Administration to Sanction her and ban her from traveling and spreading her evil ways.
Some one should be nominating this site for the annual 2024 Skeptics Anonymous Award
Mal Adapted says
Susan:
Aw, Susan, now I feel singled out. I’ll own my dross, but do you really feel that way about Piotr, Radge, Kevin, et al., and even yourself? If so, I’ll try not to take it personally!
We’ve talked about this. “Unforced Variation” includes forced responses to unforced variations of ill-informed scientific arguments and ill-conceived policy proposals. Anyone can simply scroll past the dross, and someone else can be counted on to pick out the rare nuggets and comment on them, whereupon one can go back to the original dross. Verbose challenges to any bad idea, not just outright climate-change denialism, are in the class of forced responses! Since that bi-monthly thread went away some time ago, we climate-science proponents have only this one to satisfy our personal joneses for dialogue.
Nonetheless, your plea for smaller reams of argument is well taken! I, for one, usually reach a point where I simply stop responding to further provocation by a tiresome source. There’s no reason to, when we’re all invisible, virtual identities, and physical violence isn’t a threat even for those who post under their real-life names (though cyber attacks might be, which is why I don’t). IMHO, the most satisfying response to sea-lions is to leave them wondering where you went!
Which reminds me: Bok made some constructive contributions last month, which can be revisited at will on that archived thread. He made several more good comments this month, but all of them are now missing. WTF? The mystery deepens. While my sympathies are with the harried moderators, I do wish they’d enlighten us!
Mal Adapted says
Paul Pukite:
Heh. Paul will recall “David Young”, a glib, confident denialist who showed up here five years ago. Young was eager to flaunt an opinion piece in PNAS by Tim Palmer and Bjorn Stevens, that he thought supported his claim that the CMIP ensembles used by the IPCC weren’t “fit for purpose”. Hilarity ensued, as others of us read the PNAS Perspective item and found it didn’t say what Mr. Young thought it did. Indeed the authors took pains to assure us they were confident (within published limits) in the GCMs consulted by the IPCC, and warned of those who “misrepresent doubt about anything to insinuate doubt about everything“. The piece was really about the need for models that make useful projections of local and regional climate change, as an aide to policy makers at less-than-global scales. The authors’ take-home message was a plea for funding of more computing power, to run higher-resolution, regional-scale simulations. Most of us were for that, of course, but agreed that global scale models were already plenty fit to inform the urgency of collective decarbonization.
Based on clues in his further comments, it seemed David Young’s denialism resulted from his ideological fear of collective action. He told himself climate change was a liberal preoccupation, merely a stick to beat rich people with. Models? Pfft! Scientists are all liberals committed to a collectivist agenda, and grasping for grants. And the decades long public record of propaganda and undue influence by carbon capitalists on the US government, in order to thwart collective intervention in their profit streams, is manufactured. Come to think of it, I haven’t seen Mr. Young here since then! I might have had something to do with that, in concert with his other antagonists here. No regrets.
Lastly: if it wasn’t already clear, I respect and admire Sabine Hossenfelder. I think she’s a highly effective science communicator, and clever about it. She may help US voters build a secure majority for federal decarbonization policy. I wish she’d go a little easier on climate scientists, who really aren’t in it for the grant money, and are constrained to the principle of least drama by formal training and peer discipline. But I see nothing wrong with emphasizing the upper tail of their uncertainty, if it strengthens public resolve to cap the warming collectively. As GCMs grow more sophisticated, climate realists should continue to defend modal projections regardless. IMHO, they are already quite alarming enough!
Paul Pukite (@whut) says
Mal said:
I do recall Young, who is an aerodynamics PhD at Boeing. His main concern was the pointlessness of trying to do fluid dynamics predictions, as his experience indicates that it all goes to turbulent chaotic flow (as in the flow over a wing, see here). He was also politically very conservative, which was likely the agenda he was trying to push,
OTOH, I don’t believe that ocean and atmospheric dynamics are chaotic and necessarily turbulent at larger scales. Or at least I don’t think anything has been verified one way or another, which means it is still worth researching. Two ideas to consider here (1) the concept of the “inverse energy cascade”, whereby smaller waves will feed larger waves, and thus reverse the direction from ever smaller scales of turbulence to something potentially more ordered, such as standing waves, and (2) external forcing as a means to overcome chaotic tendencies. Too many characteristics of large-scale climate behaviors such as ENSO show order rather than chaos, so the research focus should not be to give up as David Young would suggest everyone do. That’s the typical authoritarian style that seems shared among the political right. Would have appreciated having a scientific/technical discussion with Young, but that rarely turns out positive when politics is the overriding agenda.
Mal Adapted says
Paul:
Yep. As my favorite repentant ex-Libertarian professional disinformer Jerry Taylor said:
In an interview, Taylor described how he came to realize he’d been peddling motivated denial, saying:
Taylor turned out to be a genuine skeptic after all. Too bad there aren’t more like him.
Nigelj says
Elon Musk is on record as saying climate change is one of humanities main problems and we need a carbon tax. Now hes flip flopped into a climate denier and fossil fuels proponent. Perhaps hes gone crazy and embracerd idiocy for whatever reason. However I suspect hes being nice to Trump and agreeing with Trumps climate denialism, hoping for a subsidy for his Tesla EV company if Trump is elected and to generally get Trumps support promoting EV’s.. Either way, his statements on climate are very badly informed.
Kevin McKinney says
I’m not sure he’s become an actual denier–there was a moment, reportedly, during the Trump interview where he tried to steer the latter toward accepting that there is actually a climate problem. Of course, it was useless.
And as long as he works to get Trump elected, what Musk actually thinks about climate is pretty irrelevant. It does seem as if his contempt for ordinary people, emphatically including his own workers, and his own sense of entitlement are what primarily drive his choices now.
Russell says
Heinz, Pritzker, Putin, Turner, the list goes on and on
Barry E Finch says
“The current rate of SLR is around 5 mm/y. I’d suggest to get to more than a metre of SLR by 2100 requires some form of average SLR rate doubling time. That’s simple mathematics and logic”. Well now you are going ambiguous. Is “form of average” an average of the SLR over a fixed doubling time, or some average doubling time? You are nothing if not slippery. To the sensible bloke back then few months ago (you are buried in my notes) I had intended to pin that SLR curve though I’m quite sure that its quadratic (NOT exponential) function pins at the centre month, not the start or end. But that’s a winter thing because I don’t bicycle in winter any more, the road ice is too much.
Sabine says
While Americans remain extremist in their biased incomprehensible political views and take every criticism or valid comment personally and then get all emotional about any objective observations of their dire straits and dysfunctions and make believe political and economic self-fantasises, the Chinese simply get on with it, well planned, practical and effective and logical: so ho hum they’re boring. It’s what success looks like – but it still will not stop global warming or slow it down or protect ecosystem destruction:
China pledges to set a yearly CO2 emissions target
Welcome to Carbon Brief’s China Briefing.
https://www.carbonbrief.org/china-briefing-8-august-record-extreme-weather-first-quarterly-co2-fall-since-covid-dual-control-of-carbon-emissions/
Some bullet points to show how China is galloping ahead of the rest of the world when it comes to renewable energy.
Quote
NEW RENEWABLE TARGETS: Regulators published provincial targets for 2024-25 under China’s renewable portfolio standards (RPS) on 2 August, reported China Power. The targets, for the renewable share of electricity supply, increased by more than 3 percentage points year-on-year in most provinces, according to analysis published by financial outlet Yicai, “compared with a 1 to 2 points jump in previous years”.
UPGRADING THE SYSTEM: BJX News reported that China has issued a plan to upgrade its power system to “promote the construction of a new type of power system” between now and 2027. The outlet said the new system should be “safe, stable, cost-effective, flexible” and support the addition of more “clean and low-carbon” resources. A “key effect” of the plan, according to the National Energy Administration, is to improve the transmission of renewable energy from the remote desert bases to cities “at a large scale”, added the outlet.
SOLAR SURGE: Elsewhere, BJX News reported that China added 134 gigawatts (GW) of new renewable capacity in the first six months of 2024, according to the National Energy Administration (NEA) – an increase of 24% year-on-year. It added that solar made up 102GW of the total. (Total US solar capacity stood at 139GW at the end of 2023.)
‘UPHEAVAL’: China’s domestic solar industry is in “upheaval” with wholesale prices falling by another 25% so far this year, after falling by almost half in 2023, the New York Times reported. It quoted Frank Haugwitz, a solar industry consultant, saying efforts by the Chinese government to rein in the industry’s expansion have been “too small to reduce China’s overcapacity”. Bloomberg said that an increasing number of Chinese solar manufacturers “are falling into restructuring or bankruptcy”, adding that “while bigger players like Longi have so far survived billions of yuan in losses by imposing production halts and layoffs, smaller companies have fewer ways to plug financial gaps”.
‘SEVERE OVERCAPACITY’: In a meeting of China’s Politburo at the end of July, state-run newspaper China Daily said, president Xi Jinping called for “strengthening industry self-regulation and preventing ‘involutional’ vicious competition”, adding that China should “strengthen the market mechanisms” to help with “inefficient production capacity”. The outlet did not report that any particular sectors were named during the meeting. Several days earlier, Bloomberg stated that Wang Bohua, head of the China Photovoltaic Industry Association, had called for “struggling solar manufacturers [to be pushed] to exit the market as soon as possible to reduce severe overcapacity”.
The share of sales of “new energy vehicles” (NEVs) 51.1% – which includes both battery electric vehicles and plug-in hybrids – in China in July, according to the China Passenger Car Association. The trade body added that NEV performance beat manufacturers’ expectations, which it attributed to a trade-in policy encouraging consumers to replace old cars.
“The timeline here indicates policymakers still only aim to peak emissions by 2030, despite the clear likelihood that emissions will…peak much sooner,” Yao Zhe, global policy analyst for Greenpeace East Asia, said in a statement, adding that this shows China is still “underpromising”.
Li told Carbon Brief:
“This is the Chinese government rolling up its sleeves and trying to make quite an important switch…Folks have been advocating for China to really reduce its emissions in absolute terms for almost two decades. This is the mechanics of how this will happen – them actually making this switch and trying to make sure this is done in the right way by, for example, disaggregating [targets] to the local level, getting the private sector involved and trying to build up the carbon accounting system from the bottom up.”
Yao said Greenpeace expects that China’s next NDC will include a carbon emission reduction goal for 2035.
Li told Carbon Brief that China’s international pledge will then drive domestic targets, due to “how the timeline works”. He added: “The NDC [target] for 2035 has to be communicated in 2025, [looking] 10 years into the future…The job of the five-year plans for the next two five-year periods [will then be] to align with that international pledge.”
Kevin McKinney says
Not very coherent, anti-American bias aside. You tell us that “China is what success looks like,” then devote your two meatiest paragraphs to “upheaval” and “severe overcapacity”.
You are correct that China is the primary driver of the global energy transition, however. Kudos for the progress they have made. (We’ll see if they peak emissions this year or next, as some analysts project–but it seems very likely to happen before the promised date of 2030.)
But their society under Xi has other issues to address–xenophobia, gender inequality, territorial ambition, weak rule of law, and authoritarian rule., to name a few.
Peterbestyville@gmail.com says
1 in 3 cars sold globally are in China. The electric vehicle revolution is taking place there so for those who are a technology revolution to mitigate emissions then China is the leader.
Politically and economically Europe and the USA are concerned so have put in tariffs/sanctions to make them expensive.
So China has the revolution tech but the wests worry means it’s a slow process.
We need longer to adjust or do we expect to buy electric western build vehicles
Nigelj says
Sabine says: “While Americans remain extremist in their biased incomprehensible political views and take every criticism or valid comment personally and then get all emotional about any objective observations of their dire straits and dysfunctions and make believe political and economic self-fantasises, the Chinese simply get on with it, well planned, practical and effective and logical: so ho hum they’re boring. It’s what success looks like – but it still will not stop global warming or slow it down or protect ecosystem destruction:”
I think you are trolling there and making some big evidence free assertions about renewables not even slowing down climate change. You come across as just as extremist as the people you call extremists. Its sad because some of your points about American politics are valid. A gentler approach would probably generate better discussion, and on a page like this its not necessary to make such inflammatory comments to get attention.
Anyway I would say the reason China “just gets on with it” (building renewable energy) is because China is a dictatorship and so when the government wants renewable energy thats what happens, regardless of what the public wants or thinks. Dictatorships can be efficient, but personally I do not want to live under a dictatorship, and especially one rather dismissive of human rights and Chinas living standards are well behind Americas. Not even the climate crisis is a good enough reason to adopt a dictatorship system.
The reason Americas climate action seems disorganised is because America is a democracy and so every 4 years you can get a new government that might cancel the climate projects of the last gavovernment. Its an unfortunate situation. New Zealand has gone through a period of infrastructure projetcs getting cancelled in a similar way. The main parties are now looking at forming a bipartisan agreement on major infrastructure projects.
And in a democracy governments are understandably more sensitive to what the public wants (some of the time anyway) and to lobby groups. They have to be if they want to be elected.
In America political support between the two big parties and presidential candidates seems to have been rather evenly split in recent times. This might be partly a feature of it having only two main parties. For example the UK and Australia have the conservatives, Labour and the liberal democrats, so there is more choice. The UK also have bigger swings in the support each party gets. In America party suppor is more fixed and tribal, with election outcomes decided by relatively small numbers of people. Im hugely simplifying but to make a point.
Americans are not likely to choose to have a dictatorship form of government. Of course its just possible that Trump goes completely crazy and makes himself a dictator, and the fools in the Supreme Court and GOP support him. Then people would find dictatorships dont always deliver the outcomes that are good for the environment,
Thats the reality whether we like it or not. Mal Adapted expressed it all very well namely if you want climate action in America its going to be an incremental thing, and the Democrats are strongest on climate action so vote democrats.
Thanks for the copy and paste. Thats interesting.
Sabine says
to Nigelj
Is there a particular reason why you choose to talk down to me as if I’m your 5 year old granddaughter who knows nothing at all about the world or life? As opposed to someone who has a mature life long and broad knowledge of the world and my very own values and judgments about life. A person who knows and can judge for myself what is real and true versus what is false misguided or mindlessly distorted cultural political propaganda? You must have a reason surely: but you sound like a primary school teacher presenting the socially acceptable school policy.
Mal Adapted says
Sabine:
Well, Sabine, I can’t speak for Nigel, but your reaction (mysteriously missing now) to David’s mention of ProPublica, in which you told us all we were naive dupes of fossil fuel funded propaganda, was justifiably criticized as arrogant and insult-filled, not that of a mature adult.
Neither was this (quoted in subsequent replies from regular commenters):
That’s definitely not the opinion of someone who has a long and broad knowledge of the world. Just sayin’!
jgnfld says
China , yes, is extremely authoritarian. Yet in this case, the massive problems china has encountered from extreme level of coal burning caused such problems for the population that even the authoritarians became worried. Beijing was becoming well nigh uninhabitable when the new policies were initiated in 2014.. https://aqli.epic.uchicago.edu/country-spotlight/china/. It’s still bad: They are the 13th most polluted country in the world by some measures and measurably worse as a country than the most polluted regions of the USA.. But their trends on some measures–my link is to particulates and lifespan reduction–are positive, not negative, and by fairly significant margins..
They also saw/foresaw, I think, the economic potential of various green technologies in their competition with the West.
I don’t necessarily think the authoritarians did this out of the goodness of their hearts, Authoritarians tend to balk at actions that may see unrest at levels that would lead to their personal demises.
Mal Adapted says
Nigel, let me just say I’m impressed with your fairly deep understanding of US politics, apparently acquired remotely. I hope you’re right that Americans won’t choose a dictatorship, but I wonder what our founders would make of the current state of affairs. As always, we’re forced to choose between two evils, but it’s hard to imagine a greater evil than a Republican victory this fall, at least by comparison with the Democratic Party’s moderate, science-respecting platform. That approximately half the voters are planning to choose Trump, demonstrates our growing inability to rank the world’s evils. As many as half my fellow citizens appear to prefer comforting denial to inconvenient truth. Oh, my people!
Secular Animist says
Nigelj wrote: “China is a dictatorship and so when the government wants renewable energy thats what happens”
It is not as simple as that. China is a dictatorship but “the government” is not a monolith. Indeed the government INCLUDES the Chinese fossil fuel industry which remains a powerful force in determining what exactly “the government wants” — as it does everywhere in the world regardless of the form of government.
Escobar says
According to the prevailing resident ideology Carbon Brief has become a Communist insurgency, an anti-american supporter of authoritarian dictatorship of China, and should be labelled a foreign agent under the FARA Laws. Everything presented by Anika Patel must be all lies and propaganda then.
Mal Adapted says
Prevailing resident ideology? Nah. That was one commenter, singly named Sabine. Talk about a straw [wo]man!
Escobar says
https://www.carbonbrief.org/china-briefing-8-august-record-extreme-weather-first-quarterly-co2-fall-since-covid-dual-control-of-carbon-emissions/
ozajh says
I happened to read this post within minutes of reading on Peter Sinclair’s site about recent massive Solar Panel imports by Pakistan.
https://thinc.blog/2024/08/15/pakistan-addresses-blackouts-prices-with-solar/
I wouldn’t be completely surprised if there was a political correlation here, with the Chinese government heavily subsidising the sales. Chine has often previously lined up with Pakistan on ‘enemy of my enemy’ grounds. (And I’m not saying that a large quantity of renewable electricity in Pakistan isn’t a good thing!)
Barry E Finch says
Nigelj 14 Aug 2024 at 4:15 PM “My recollection is that James Hansens findings are that above 2 degrees you kind of reach a tipping point where glaciers start to dramatically speed up their flow into the oceans”. My recollection is that Eric Rignot said 2 things “when a marine-terminating glacier’s ice shelf is gone it speeds up to 6-7 times its present” and another time with no explanation “a SLR of as much as almost 5m / century is possible” so I instantly applied my high mathematics skills same as “Geoff Miell” and calculated ((2,200+600)*5.5) * 100 / 360 = 4,280 mm / century from ice loss AFTER ALL THE ICE SHELVES ARE GONE. Throw in 200 mm / century for expansion and the insult and you got 4.5 metres per year after all ice shelves gone. I started studying ice shelves and got through about 40 of the glaciers on Greenland in 50 hours or so before losing interest and moving on. Also, Eric then confused me by stating later that grounding line retreat was far more important than ice shelf or no ice shelf. Still I suggest you could get a good working prediction by figuring out when each ice shelf will be gone so … Go For It because ….. I absolutely definitely NEVER will (can’t even understand my own hundreds of lines of references, notes and calcaultions about it from 2018). The “Geoff Miell” of course reliably brings a lazy nothingness (no study work) to the science table on this century, multi-century prediction topic, similar to a truly-awful, lazy “Paul Beckwith” bloke.
Barry E Finch says
Tomáš Kalisz 14 Aug 2024 at 2:30 “global water vapour concentration increased … while concentration of greenhouse gases remained constant” is an impossible self contradiction unless it happened that CO2+CH4+O3+N2O concentration decreased by an amount equalling the H2O gas concentration increase.
Tomáš Kalisz says
In Re to Barry E Finch, 16 Aug 2024 at 9:55 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823788
Dear Barry,
In the article, the authors tested the influence of water availability for evaporation from the land on global climate. In this sense, it is understandable that they kept the atmospheric concentration of all non-condensing greenhouse gases in their model constant.
They found out that the “desert land” provided higher average water vapour concentration and lower global precipitation than the “swamp land”. It is an open access article, which you can read on
https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1/pdf .
It is my understanding that in their previous work
https://marysalague.com/wp-content/uploads/2023/06/halfland_main_r2.pdf ,
modelling the influence of land disctibution over the globe using an ISCA climate model that considers only water vapour but does not include clouds, they arrived at qualitatively different results.
Putting more land into tropical region (and thus decreasing water evaporation) in this case caused a decrease in global average air humidity and global climate cooling.
Personally, I assume that the model comprising clouds is more realistic than the previous one, however, I do not dare to assess if it is indeed realistic enough that the results are at least qualitatively correct (and that they perhaps will not reverse again if an even more sophisticated model is used instead). This was one of the reasons why I asked if there is another similarly directed study using a different model, and if a climate scientist could comment.
Greetings
Tomáš
Barry E Finch says
JCM 13 Aug 2024 at 1:34 “trace gas reduction” S.B. “well-mixed greenhouse gas reduction”. Much as I dislike the “greenhouse” phrasing that somebody decided was best, we are stuck with it. If is mentioned “infrared-active gas” I expect >99% would think “Whaaaat?”
JCM says
the language sensitivity is understandable Barry – but, as previously discussed, it’s a shorthand to avoid misunderstandings such as those in: https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823788
A critical aspect of terrestrial forcing is its coupling with large ocean reservoirs, which operate at their energy limit and supply moisture to the atmosphere at saturation. The ocean’s surface response is strictly energy-limited and follows the temperature-dependent equilibrium partitioning of turbulent flux.
Since others have provided no quantitative analysis – only unsupported, ideologically-driven, and overtly-biased hand-waving – I’ll reference the ongoing widely discussed idealized model. Using this model, temperature is linearly related to ET suppression at -0.16 mm/day/K, incorporating all feedbacks. Column water vapor increases by 1 mm/K. This idea is inconvenient for certain storylines so it seems to be rejected automatically.
Nevertheless, ERA5L is giving a trend ET -0.2 mm /yr for the recent 30 year climatology.
When integrated over 30 years, this equates to about -0.02 mm ET/day. The maths could be verified as there is some rounding happening.
With a coupled model temperature relation -0.16 mm/day/K, the 30-year change in ET in reanalysis corresponds to a climate response of about 0.13 K, or roughly 0.04 K per decade assuming equilibrium. Include plus and minus huge uncertainties.
Using the idealized ET suppression model and ERA5L data, we should expect a 30-year global increase in column water vapor of about 0.1 mm due to biogeophysical effects, in addition to the biogeochemical carbon cycle effect. This is why the shorthand trace gas distinction is convenient in this context.
The change in shortwave radiation (SW-in) is approximately 2 W/m2/K in equilibrium, due to the shortwave CRE feedback to ET suppression. The so-called “humidity paradox” could be explained by terrestrial moisture limitation combined with vast expanses of energy-limited ocean. This appears to be associated with greater energy flows through the system.
In the CMIP6 ensemble, standard radiative forcing is expected to cause (somehow) a huge stabilizing increase in terrestrial ET of about 0.3 mm/year. However, reanalysis shows a change -0.2 mm/year, a difference of -0.5 mm/year over the recent climatology, indicating the expected stabilization is missing. This difference equates to roughly 0.1C per decade and 0.3 mm of unaccounted column water vapor. Fluxcom yields a difference 0.6K/century. The effects under various sky conditions, both clear-greenhouse and cloudy-shithouse, are critical. But, it is all very uncertain.
The example provided is just one element from an idealized experiment where NCAR assisted to plug a simple land interface model with the CESM. Additional factors discussed in ecological climatology include various other changes as well.
Gordon Bonan’s work describes these processes conceptually: ecological destruction increases surface reflectance and reduces the energy available to drive the hydrological cycle. It decreases evapotranspiration and increases sensible heat flux, thus lowering humidity and potentially inhibiting cloud formation. It reduces surface roughness, limiting heat transfer between the biosphere and atmosphere, which may warm land surfaces and decrease convective overturning. It also diminishes biological ice condensation and precipitation nuclei, affecting the cloud and energy budget. The net effect of these changes is unknown, poorly monitored, and largely outside the scope of the UNFCCC.
Summaries of the climate science provided to policymakers typically offer only simplified accounts, such as the cooling effect of increased surface reflectance from ecological destruction, suggesting that it is offset by the trace gas effects of the missing carbon sink. It seems that because biogeophysical monitoring and inputs are not prioritized, they are treated as if they don’t exist. Meanwhile, CMIP/AMIP models still fail to adequately parameterize surface factors (e.g., vs ERA5), leading to poor reflections at TOA (e.g., CERESMIP).
Tomáš Kalisz says
in Re to JCM, 18 Aug 2024 at 8:51 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823822
Dear JCM,
Your explanations look as an excerpt from an article. Could you provide the reference, or is it a yet unpublished work (perhaps the article you mentined in your previous post?)?
Greetings
Tomáš
JCM says
To Tomas,
the discussion combines elements from Kleidon’s “Working at the limit: a review of thermodynamics and optimality of the Earth system”, to Lague’s “Reduced terrestrial evaporation increases atmospheric water vapor by generating cloud feedbacks”, and various elements from Bonan’s research.
Specifically, the linear relationship of -0.16 mm/day/K for ET suppression was simply derived from Figure 4, panel (a) in https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1 by dividing the total change in mm/day for land by the total temperature change.
Recently, Clair Zarakas and collaborators, including Bonan, provided a comprehensive summary of land element parameter ranges and their significance in: “Land Processes Can Substantially Impact the Mean Climate State”.
Specific Key Points from Zarakas:
“Assumptions about land processes substantially impact mean state terrestrial temperature and precipitation.”
“Land parameters influence climate predominantly through changing evapotranspiration rather than through other mechanisms.”
“Warming driven by land processes activates different atmospheric feedbacks than radiatively-driven warming.”
https://eartharxiv.org/repository/view/6605/
Additionally, it is the soil hydrology parameters, not the plant physiology change as observed from space, which dominate the influence:
“Three soil hydrology parameters – frac_sat_soil_dsl_init, d_max, and fff – had the largest impact on global mean temperature. Land surface temperature change in the land-only perturbed parameter ensembles (PPE) were generally much smaller than those in the coupled PPE, consistent with the fact that atmospheric feedbacks substantially amplify the land surface temperature response to changing land surface properties (Lague et al., 2019).”
“”While land modeling has substantially expanded beyond its initial scope of providing lower atmospheric boundary conditions into its own subdiscipline and research community, land models’ continued role as atmospheric boundary conditions means that a broader climate science community must engage with land processes (and uncertainty herein) in order to understand and model the physical climate system””
As you may have noticed, some contributors mistakenly believe that greenhouse climate politics and the CO2 problem encompass the entirety of global change science. This is totally false. An enriched understanding requires a broader view that appreciates the scope of this field, not merely what’s spoonfed in fancy promotional brochures. Historically, climate studies were part of Geography, integrated with systems and ecology. However, since the climate policy frameworks of the 1980s and 90s, certain barriers have emerged in academia, limiting the convergence of multidisciplinary research. This narrow perspective is often perpetuated by amateur enthusiasts and even some academic activists who naively assume that hydro-ecologies merely respond passively to atmospheric change. This view is not only misguided but also fundamentally wrong (despite their ongoing red-faced-steam-coming-out-of-the-ears objections). Some contributors also seem to fear that acknowledging the significant human impacts on global change and their relationship with climate dynamics might upend everything they believe to be true. This is also totally false.
The range of factors is documented in introductory climate texts, particularly those focused on the surface-atmosphere boundary layer. This I know for certain! It’s not controversial and these processes are essential in governing heat dynamics on Earth; it’s just rather not the focus of the narrow climate politics, newsmedia, public outreach, fashionable grants, awards, and television programs. However, I admit that when regional or global ESM biases emerge and influential people scratch their heads looking only at industrial aerosol or gas emission inputs I wonder what the heck it is they are thinking. I believe somehow the view of environmental change has been mishandled in such a way that it has been reduced to “pollution” which becomes ingrained in children for life. No amount of mathematical rigor or astrophysical brilliance seems to overcome this shortcoming.
That said, atmospheric pollution matters and it’s critically important to handle using globally prescribed targets. Additionally, profound ecological destruction and what we’ve done to landscapes must also be remedied. This can be handled in short-order using locally-oriented, diverse and well-understood solutions (don’t expect your favorite climate celebrities to know anything about that). Admittedly, this is messy and inconvenient from a global governance perspective; but, conditions can be improved quickly with localized, well-understood methods, offering benefits in a matter of years, not centuries.
Tomáš Kalisz says
In Re to JCM, 20 Aug 2024 at 2:57 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823882
Hallo JCM,
Thank you very much for your explanation.
Personally, I am somewhat sceptical about drawing quantitative conclusions from Lague 2023. I already wrote to Piotr that if we look e.g. on panel 3 in Figure 4, we see that the difference between the “desert land” and the “swamp land” in annual sum of precipitation, as predicted by the model used by authors, is remarkably small.
In deserts of the real Earth, lack of water available for evaporation seems to cause much more dramatic difference in precipitation patterns.
Greetings
Tomáš
Piotr says
Tomas Kalisz. joining JCM in his attack on Lague et al 2023 they used before a proof of their claims:
In deserts of the real Earth, lack of water available for evaporation seems to cause much more dramatic difference in precipitation patterns
Only in the deserts of your brain, Mr. Kalisz. On the real Earth – we have such a thing as “wind” – hence the results of your own source that you both try now to disown.
JCM says
Thank you Tomas, this is very interesting.
Consider that moisture cycling rates are influenced by both ecosystem characteristics and temperature.
For example, in today’s Earth, a desert ecosystem may exhibit ET rates of 0.5 to 4 mm/day, while a wetland might range from 5 to 15 mm/day, depending on its geographical location. This results in a global average difference of about 6 to 7 mm/day between wetlands and deserts. However, in the extreme scenario, this difference narrows significantly to just 1.3 mm/day when comparing a total swamp to a total desert (with ocean). That seems surprisingly small.
It’s important to consider the continuum of globally averaged temperatures depicted in the extreme scenario, in addition to ecological variation.
Comparing the 6 or 7 mm/day difference based on current ecological conditions in the mean climate state of today to a planet with a significantly different GSAT could be misleading. It’s only half the story.
Recall, increasing moisture availability is typically associated with decreasing temperatures. When examining the hydrological cycle, these factors tend to oppose eachother. Specifically, an optimum arises by riding at the intersection of moisture availability and energy limitation. As globally averaged temperature decreases, also the energy becomes more limited.
Therefore, a much cooler planet than today’s Earth is likely to exhibit a globally averaged ET difference between wetlands and deserts that is less than 6 or 7 mm/day. Conversely, a much warmer planet might show a greater difference. Imagine an oasis surrounded by desert – the oasis will exhibit significantly higher ET compared its surroundings. As GMST increases, so does this contrast.
While the moisture-dependent variation could be substantial, the mean change aligned with GMST may remain minimal due to the optimal balance between energy and moisture availability. For this reason I think it’s useful to digest Kleidon’s thermodynamic constraints framework.
A similar principle applies to ocean v land. As continental moisture becomes more limited and GSAT rises, the oceanic latent flux increases to match the new (increased) energy threshold. This establishes a new steady-state optimum with higher GMST and increased oceanic evaporation.
The ocean’s response is inversely related to changes in land ET. In the extreme CESM scenario, the ocean-land ratio is 0.43/-1.3, meaning that for each area-unit of moisture reduction on land, the ocean compensates with an increase of 0.3 due to higher air temperatures. The overall global difference in this new steady state reveals a global mean atmospheric moisture regime not drastically different from other steady states.
In summary, the global mean difference in atmospheric moisture dynamics when varying GSAT is minimized by the opposing factors of moisture availability and energy limitation. Under an extreme scenario in the CESM, with 8K temperature difference, the global mean change in latent flux is a mere 0.19 mm/day.
This compensation is illustrated in Figure 3, where dry continents see the ocean almost entirely compensating for the reduction by utilizing the increased energy availability. This is accomplished with a higher global mean temperature. The new steady-state precipitation patterns and wind anomalies are shown in Figure 12.
Finally, acknowledging your concerns, it’s important to note that, based on the experience of CMIP, other ESMs besides CESM are likely to exhibit significantly different responses.
Tomáš Kalisz says
In re to JCM, 23 AUG 2024 AT 10:16 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-823940
Hallo JCM,
I am fine with a small difference in global latent heat flux between the swamp land and desert land extreme scenarios.
What I see somewhat suspicious is a relatively small difference between land and ocean in both scenarios. Makarieva et all are afraid that anthropogenic disruptions in rain recycling over continents, caused by improper land use, might have caused, at least in some regions, a feedback loop that resulted in a complete desertification of an originally humid landscape.
I have no idea in which extent are mechanisms like rain recycling included in state-of-the-art climate models generally, and in the CESM used by Lague et al specifically.
This would be my question to climate modellers, if there was any willing to reply.
Greetings
Tomáš
JCM says
Thank you Tomas,
I want to caution against interpreting the small relative mean change in mm/day as evidence for a lack of profound climate change. The results from CESM seem to imply a large SW cloud radiative response to changing properties of the landscape. This suggests a significant departure in variability of the moisture regime alongside changes in GMST.
I typically discuss this change in variability as increasing hydrological and temperature extremes. Switching from gentle daily rainfall to highly variable and infrequent precip is a profound climate change, despite this being obscured by smearing it into the avg mm/day in model summaries.
From a hydrological perspective, beyond the scope of Lague, a significant decrease in precipitation frequency combined with an increase in intensity with GMST accelerates desertification. This happens because catchments become less efficient due to saturation or infiltration excess flows, in addition to direct destabilization. This is the flipside relation of flood and drought – as rainfall is harvested less efficiently, this compounds erosion & desertification. The most extreme visualization is urban stormwater through concreted drains. Consider the downtown core of any metropolitan area as completely desertified.
Recognize additionally that from my hydrological and soils perspective we typically refer to desertification as specific to the soil properties themselves, not directly associated with the avg rainfall. That is: desertification = land degradation, increasing bulk density, loss of fertility, loss of soil organic matter, slowing or loss of nutrient cycling, loss of life.
Regarding Makarieva, early in my involvement here, Gavin Schmidt poo-poo’d discussions on her work, partly due to her unfounded criticism of model physics. After reconsideration, I believe current-generation models might actually capture these mechanisms given the right input. This is supported by Lague’s use of the CESM.
While I can’t speak for those designing complex process models for inclusion in CMIP, I understand that the goal is to minimize tweaking specific mechanisms. Instead, the focus is on setting boundary condition constraints, like initial optical thickness and surface parameterization, and letting the governing physical equations determine the outcomes in global circulation, temperature, and precipitation patterns.
More recently, Makarieva has been highlighting discrepancies between observations and models regarding the lapse rate and the expected lapse rate feedback. She notes that “current models assume that as the planet warms, the temperature lapse rate should slightly decrease, following the moist adiabat (the so-called lapse rate feedback, Sejas et al., 2021). While this is robust across models, observations indicate an increase in the lapse rate, especially over land, consistent with radiative forcing due to changing non-radiative fluxes, including those caused by land cover change.”
In my view, Makarieva’s point holds without needing to introduce new model physics; rather, it may be a critique of the largely unconstrained and unmonitored surface parameterization.
cheers
Piotr says
JCM: the language sensitivity is understandable Barry – but, as previously discussed, it’s a shorthand to avoid misunderstandings
Your use of the “trace gases” has the goal OPPOSITE to avoiding misunderstanding:
First, the term is poorly defined – there is NO natural nor generally agreed upon definition of the word “trace” in the context of the greenhouse effect. In analytical chemistry, a trace element is “one whose average concentration of less than 100 parts per million (ppm).” By their definition – CO2 is NOT a trace compound – it doesn’t have and never had in the last couple bln years, conc. <100 ppm.
Second, the term is scientifically useless in the context of AGW – since almost all AGW is driven, directly or indirectly, by what you call “trace gasses” while the “non-trace gasses” do nothing (N2, O2) or are merely feedbacks – PASSIVE amplifiers of the effects of the “trace gases” – if we increase conc. of trace gases – water vapour would make the resulting warming larger, if we we decrease “trace gases” the water vapour would make the resulting cooling larger.
Therefore, water vapour is not a forcing, and as such won’t reduce the RELATIVE importance of “trace gasses” in driving AGW, quite the opposite – it makes the climate not less, but MORE sensitive to what we do to “trace gases” in the atmosphere.
Third – ironically, by being “trace amounts” – it is easier for humans to CHANGE them and thus alter their radiative forcing. Contrast this with water vapour – where natural fluxes are MASSIVE, and the residence time many orders of magnitude SMALLER than those of CO2 et al. – hence it would require “mindboggling” effort and money to change these massive natural fluxes in any significant way,
Fourth, the use of “trace gasses” to the general public is misleading – by implying that a “trace gas” can only have a “trace influence” on the climate. And the Occam razor suggest that it is YOUR reason for insisting on using this phrase – as part of the old deniers narrative “Anything but GHGs” – if the trace gases had influence corresponding to their (trace) concentration, then this would support your attack the climate science by blaming it for:
“ the planet’s land degradation and loss of native ecologies [due to] an artificial fixation and overemphasis on the outputs of trace gases ”. JCM
And promote your non-trace gas (water vapour) – as an viable alternative to the AGW mitigation INSTEAD of the “ artificial fixation and overemphasis on the outputs of trace gases“.
Piotr says
Re: Barry E Finch Aug. 16 – I doubt you will convince JCM – he INSISTS on using “trace gases” for a very specific reason – to imply that “trace” gases have only “trace” importance to AGW.
He needs it to push an old denier narrative “anything but GHGs” – if the effect of “trace” gases are indeed “trace” too – then it is intellectual honest to call for a switch of the the research efforts and money from “trace” gases mitigation to gigantic (i.e. non-trace) geoengineering of the water cycle
And for a better effect, lets blame the climate science for:
“ the planet’s land degradation and loss of native ecologies [due to] an art