This month’s open thread on climate science topics. Arctic sea ice minimum is upcoming, global temperatures running at (or close) to record levels, heat waves, new reconstructions for the last 2000 years, etc… Surely something there to discuss?
Climate science from climate scientists...
“Arctic sea ice minimum is upcoming, … Surely something there to discuss?”
The NSIDC News & Analysis a week back was projecting that 2019 will end up at 3.75Msqkm, the 2nd most melty minimum behind 2012 and ahead of 2016 & 2007. This mirrors the message from the JAXA SIE data which shows 21 Aug 2019 SIE at 4.47Msqkm, 2nd lowest for time of year, and running five days behind 2012 and six days ahead of 2016 & eight ahead of 2007.
If the 2019 melt ended today, it would sit behind the minimums of 2007, 2011, 2012, 2015 & 2016 and still a whisper behind 2018. Assuming the remaining melt of 2019 matches the melt in these yet-to-be-matched years, 2019 would sit comfortably in 2nd pace with SIE in the range 3.5M to 3.9M sqkm. behind 2012 (3.18Msqkm) and ahead of 2016 (4.02Msqkm) & 2007 (4.07Msqkm). (Mind, as the minimum draws closer and the average rate of daily melt drops, the possibility of a short period of unexpected change (or lack of change) in SIE levels signiificantly effecting the minimum becomes larger, as in 2016 when a vigorous melt season pulled up early with the minimum arriving on 7 Sept.) The JAXA SIE anomaly (with the annual cycle removed) is graphed out here (usually 2 clicks to ‘download your attachment’).
The mid August PIOMAS analysis shows Arctic Sea Ice Volume no longer the lowest on record but sitting 2nd lowest, 130 cu km above the lowest 2012 while still pulling away slightly from =3rd placed 2017 & 2011 which sit 490 cu km above 2019.
Greenland melt also looks to be a 2nd place for Surface Mass Balance for the 2018-19 melt season (behind 2011-12) although, as NOAA’s Greenland Ice Sheet Today page makes plain, snowfall is another variable. So while the snowier 2016 season will probably push 2019 into third for Cumulative Melt Day Area, the less-snowy 2019 will see net Ice Mass Loss close to the 2012 record.
And down in warmer climes, the 2019 Atlantic hurricane season is the least active season for a couple of decades, although still with some months to go. Despite the slow start, just a fortnight ago NOAA were predicting an above-average season so things might be getting livelier in coming months.
Killian @148,
I think your ‘paraphrasing’ of my comment @141 says a whole lot about you but very little about my comment @141.
Kevin McKinney @145, the phys.org article looks plausible to me. It’s unlikely that a mainstream science mag would get that idea wrong. We all know there’s a lot of geothermal energy down there that is easily enough tapped by human activities.
The geothermal energy would be a small component of total global warming given the extent of land areas devoted to drilling combined with the temperature trends in those areas, so its just something adding a little to AGW, and another reason why oil drilling is a problem.
Of course the claims sometimes made that geothermal energy largely explains climate change dont make sense.
“Is there science linking the current high annual increase in MLO CO2 levels to some mechanism driving your skyrocketry?”
Some of the high MLO numbers might relate to the larger than normal number of fires in the Amazon this year as below. Many are suspected to have been deliberately started to clear land, given the President Bolsonaro has made it plain he couldn’t care less about protecting the rainforest. So the mechanism is not primarily a natural sink feedback right now, but forest fires globally are still generally getting larger in area and more frequent as a result of climate change.
https://edition.cnn.com/2019/08/21/americas/amazon-rainforest-fire-intl-hnk-trnd/index.html
@Killian, #147:
Believe it, or not, I already saw posts (I think it were comments on youtube, or somewhere else in a comment section after an article), where the underestimation yielded the commentor to say: they underestimated, so their models were wrong. So we cant believe them, and hence there is no human caused global warming.
No joke. Some people write such things!
What’s hidden under the Greenland ice sheet? | Kristin Poinar (from 2017)
Seems to me there ought to be, and it should be relatively easy to create, a comparison model between (A) what the global temperature record would have been if society had, at the outset of the Industrial Revolution, opted to only use renewable sources of energy (wind, solar, hydroelectric, etc.) rather than coal, gas and oil, and (B) the temperature record that we have now. Such a comparison would illustrate very well, in an easy-to-understand manner, the tremendous gains that can come from leaving fossil fuels in the ground.
If such illustration already exists, I haven’t come across it.
Thank you!
S. B. Ripman @157 — Use the average global temperature of the 1890s as a guide to the expected global temperature now sans carbon dioxide emissions.
Is anybody able to help me with my query #133, in which, regarding surface air temperatures, I ask:
‘If we are seeing 50 C in these places today, what climate-related processes will prevent us from hearing of …60 C in the same places in 10 years time, and … seeing 70 C there in twenty years?’
Nothing to see here… move along.
Rare ‘sudden stratospheric warming’ to blast NZ with icy ‘streamers’
https://www.newshub.co.nz/home/new-zealand/2019/08/weather-niwa-warns-rare-sudden-stratospheric-warming-to-blast-nz-with-icy-streamers.html?fbclid=IwAR2YEEX6rgBZn-EUHpRg11z2isjd_-5VczZL62azFEEiuplDO5Y-f80I_ow
(I will let you know how it pans out, from here at 46 degrees south.)
NigelJ 154, re forest fires. One can say that indeed the Amazon forest fires, and many other human-started fires like the clearances for palm oil are a feedback of climate change. I suggest that humanity is reacting to worsening climate conditions by its increasingly frantic efforts to produce more, to grow more in places where essential food supplies will grow, regardless of the net environmental impacts of that farming practice. So, in the big picture, humanity is as much a part of the potential positive feedback loop as every other natural living system which is suffering from climate-change-to-date. Pine beetles breed and eat, coral polyps die, humans put GHGs into the atmosphere. I guess we have the (forlorn) hope that humanity will not mess its own nest, but our track record in that regard to date is abysmal, and there is no way we will come to our collective senses at a useful scale in time, IMHO.
Adam Ash @133&159,
The absence of a specific location for your 50ºC tempertures does make any reply difficult. So let me assume a location that fits the bill, perhaps Rajasthan that has reportedly suffered such temperatures this year. Now the recent heatwave can be put in context.
According to BEST, Rajasthan has an average monthly high temperature for May of 40.6ºC (1951-80 average high) so a heat wave ten degrees above is surely not unexpected. Finding previous record-breaking high temperatures for this region might be a better measure (the 2018 record of 50.8ºC broke the 50.6ºC record set in May 2016 but prior to that….) but without them we do have the monthly average May highs from BEST. Using this, your projection forwards of 60ºC in ten years and 70ºC in twenty does not project backwards as the record high temperature cannot have been anywhere near as low as 40ºC ten years ago if the 1951-80 climatology for the entire state was 40.6ºC.
A quick look at the BEST high monthly May averages (1875-2013) for Rajasthan shows very little increase for May (+0.04ºC/decade, not statistically significant at 2sd) with record monthly averages (since 1875) running:-
1875 …. ….+42.28ºC
1895 …. ….+42.32ºC
1905 …. ….+42.57ºC
1948 …. ….+42.87ºC
1988 …. ….+42.10ºC
2010 …. ….+43.17ºC
That is not to say that AGW is not leaving its mark on heat waves in Rajasthan. While “annual mean temperatures across India are increasing … consistent with human-caused climate change,” reportedly “heat waves in a relatively small area of India [Rajasthan] are becoming more frequent and more intense [although] this is not true for most of [India].”
161 Ash said I suggest that humanity is reacting to worsening climate conditions by its increasingly frantic efforts to produce more, to grow more in places where essential food supplies will grow
Nope. Q: What isit being burned down FOR?
O 155:
Stop concerning yourself with idiots and criminals. We have passed the social tipping point for awareness.Focus on the tipping point for awareness of true sustainability.
MAR, dear sir, we are in no way surprised.
Jetstream – I heard different information about it.
1) The climate change yields to slower (polar) jetstream, which is more meandering.
2) The climate change yields to faster (polar) jetstream with more turbulences.
More meandering (1) and more turbulences (2) looks mathching to me.
But slower (1) and faster (2) does not.
Any ideas about this?
I’m pretty sure we are crossing some ultimate tipping point in Europe right now, the ongoing extreme drought marks the end of Europe as we know it. Southern Europe is turning into a desert and the rest of Europe is turning into steppe. The entire eco-system is falling apart. Groundwater tables ever more falling for years now. All insects almost gone, bird populations falling rapidly, amphibia populations ect ect as well and the forests (correct term: Wood plantations) are collapsing. It’s a multifactorial, vicious circle. You think I’m only fear mongering? Just wait and see.
Hands down, I’m done after rouhgly 35 years of useless weeping and warning. What’s the sense of being a Kassandra? The only sense I see is just a small private pay-off of being such an obtrusive realist my whole life:
I didn’t hoard material shit and I didn’t put any own children into the frying pan. That’s it.
I’m sick and tired of fighting such a futile battle. I’m done.
Hail capitalism, hail the “elite”, hail all calculated optimism and hopium, hail the military-industrial complex and finally the fossil fool industry!
Over & out.
Not a good piece of news:
https://www.cbc.ca/news/canada/kitchener-waterloo/hotter-larger-fires-turning-boreal-forest-into-carbon-source-guelph-research-1.5255815
#153, nigel–
I would have thought so, too, but IMO the article is rubbish.
Yet that’s exactly the claim that the article makes, or at least strongly flirts with:
And again:
The specific claim that they make based on their research is not obviously unreasonable, at least:
And since ‘leave it in the ground’ is the basic conclusion either way, it’s arguably not mischievous in the sense of discouraging mitigation measures.
However, resurrecting one of the late, great Hubert Lamb’s less-good ideas is not a good sign, and this bit is flatly false:
Adam @133,159
There are several factors that tend to keep a lid on temperature increases around what are already the hottest places on the planet. They are all low altitude, low latitude, desert or semi-desert. The significance of the dryness is that the strong summer sun can go into heating up the ground, which heats up the air from the bottom. In wetter regions, some of the heat goes into evaporating water from the ground and vegetation.
You can add area to the 50C+ region by drying out a steppe, but it is harder to add to the absolute maximum temperature. Heat is dispersed vertically, because hot air has relatively lower density and rises. The hotter it gets, the deeper the vertical dispersion. The hottest temperature obtainable is limited by how hot you can get aloft, say 5km altitude, as well as the surface. The heat tends to be dispersed horizontally aloft, and the overall rate of global warming is slower than at the surface.
Also, the rate of radiation back to space increases rapidly as the temperature increases. This means that the hottest places radiate heat back to space the fastest, and are the most difficult to warm up further.
Increasing heat beyond the limits of human endurance depends on humidity as well as temperature. The combination of heat and humidity already is very extreme in the vicinity of the Persian Gulf, and problem areas will become more widespread at the tropical oceans continue to warm.
A friend pointed me to Rex Fleming’s recent book “The Rise and Fall of the Carbon Dioxide Theory of Climate Change”. I was surprised to see it was published by Springer, in the past a very reputable publisher. I did not find any useful reviews of the book, and the book no longer seems to be on Springer’s website. It would be useful to have an authoritative review of the book. All I found on the web were reviews and interviews from the denialist camp.
Mr. Benson, no. 158: Thanks for the advice. But doesn’t that assume that all of the temperature rise is due to fossil fuel usage? Surely other factors, including CFCs, deforestation and conversion to farming and ranching, growth of cities and highways, growth of factories and machinery, growth of human population and diminishment of other species, etc., fit into the mix. Isolating and highlighting the contribution from oil, coal and natural gas would seem to provide a good vision of what can be gained by leaving fossil fuels in the ground.
Kevin McKinney @168, regarding the oil fields and geothermal energy article. I still maintain the science was ok, but I think you are right the way they wrote the article created the impression they were flirting with geothermal energy as a main cause.
The geothermal energy article failed to really draw attention to how much energy oilfields would really add into the system. They must at least have a rough idea and I would think its obviously small. By leaving doubts, and quoting past junk science on the issue this all plays into the hands of climate denialists, who could quote the entire report as suggesting geothermal energy is a big cause of warming, without needing to even cherry pick parts of it.
I’ve seen this sort of problem in one or two other well intended articles; its almost a naive style of communication that fails to qualify things adequately, and as a result the writers could end up on the back foot having to defend and explain their position. People don’t want to be having to constantly do that, yet its what warmists end up doing. Writers need to qualify things better and really boldly.
John Pollack,
Good points. I’ll add that maximum temperature isn’t the only issue. Humans can take the heat of the day pretty well as long as they have a cool night in which to recover. So as nighttime temperatures increase a region can become deadly even if daytime conditions haven’t significantly worsened.
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GL083686
Future Heat Stress During Muslim Pilgrimage (Hajj) Projected to Exceed “Extreme Danger” Levels.
Abstract
The Muslim pilgrimage or Hajj, which is one of the five pillars of Muslim faith, takes place outdoors in and surrounding Mecca in the Saudi Arabian desert. The U.S. National Weather Service defines an extreme danger heat stress threshold which is approximately equivalent to a wet‐bulb temperature of about 29.1 °C—a combined measure of temperature and humidity. Here, based on results of simulations using an ensemble of coupled atmosphere‐ocean global climate models, we project that future climate change with and without mitigation will elevate heat stress to levels that exceed this extreme danger threshold through 2020 and during the periods of 2047 to 2052 and 2079 to 2086, with increasing frequency and intensity as the century progresses. If climate change proceeds on the current trajectory or even on a trajectory with considerable mitigation, aggressive adaptation measures will be required during years of high heat stress risk.
https://link.springer.com/article/10.1007%2Fs40641-019-00140-z
“On the Causes and Consequences of Recent Trends in Atmospheric Methane. Carbon Cycle and Climate (K Zickfeld, JR Melton and N Lovenduski, Section Editors) First Online: 22 August 2019” (OPEN ACCESS)
“There is evidence for various contributors to emission increases or reduced removal of atmospheric methane. No single process can explain the methane rise and remain consistent with available data. Reconstructions of recent changes in the methane budget do not converge as to the dominant contributor to the rise. A plausible scenario includes increasing emissions from agriculture and fossil fuels while biomass burning is reduced, with possible contributions from wetlands and a weakened sink.”
Thanks John, Al, et al. I guess my main point there in regard to maximum survivable temperatures is that mother nature pays no heed to human physiology and thermal management, so there is no natural system which will prevent rising temperatures pushing through a human-survivability threshold without out any regard for how we may feel about it. So if its getting markedly warmer where you live today, you should not hold out any hope that the warming will stop before it becomes unbearable and you have to migrate to cooler climes, or perish.
Topic: Original Data and Graphics:
Hello I was looking for the overview-graphics on the global temperature since millions of years, which I have seen often, but did not remembered where it was.
After long search I found it was on wikipedia:
Palaeotemp
Later I found this article:
Can we make better graphs of global temperature history?
Interestingly there are links to some datasets.
Thats a good idea, but already two files are missing:
https://www.gfy.ku.dk/~www-glac/data/NGRIP_d18O_50yrs.txt
and http://hadobs.metoffice.com/hadcrut4/data/current/time_series/HadCRUT.4.2.0.0.annual_ns_avg.txt
are not available.
Would be good if the new links could be placed there.
Also I think it would make sense to push these data onto certain archive-sites, just in case….
[Response: This is a better effort: http://gergs.net/all_palaeotemps-2/ – gavin]
I see Judith Curry is trying to emulate one of the Gentlemen Who Prefer Fantasy (Matt Ridley) by branding RPC8.5 (and its successor SSP5-8.5 of AR6) as “borderline implausible” and part of the IPCC’s “Alice in Wonderland syndrome of scenarios that include too many implausible assumptions.” Her grand paper (which she isn’t going to bother to get publshed in full) is entitled ‘Climate Change: What’s the Worst Case?’ (linked in this weblog)
The denialist viewpoint is that too much attention is being given to the worst-case scenarios of AGW. As well as SLR, Curry considers global temperature rise associated with scenario RCP8.5. Unlike Matt Ridley who simply ignored RCP8.5, Judith Curry is more reasoned. In doing so, and as Curry’s paper is addressing the worst-case scenario, she decides “it is difficult to see how this paper could be categorized at ‘contrarian.’”
The argument runs that RCP8.5 is dependent on assumptions on economic growth, population growth and fossil-fuel use that are collectively “borderline implausible.” Of particular note is the continued extensive use of coal. Now, if you tot up the FF emissions within RCP8.5 from today to 2100, they do total 1,700Gt(C) and FF reserves stand today at 1,200Gt(C) with two-thirds of that coal. If the reserves remained at that level then, even with a return to extensive coal-use, RCP8.5 looks a tad unattainable. Except FF reserves of oil and gas both expanded 50% in 20 years (1995-2015). If that rate continues, there will be well-enough to attain RCP8.5, and that without any skyrockety additions to atmospheric CO2 which would be an incredibly serious worry under RCP8.5.
And if RCP8.5 can be dismissed from policy decision-making by calling it “borderline implausible,” that means “the IPCC AR5 (2013) likely range of warming at the end of the 21st century has a top-range value of 3.1ºC**” as the next worst-case scenario is RCP6.0. And that top-range-value-of-the-worst-case 3.1ºC**, already a “more moderate amount of warming,” is itself derived from “climate models with values of the equilibrium climate sensitivity that are larger than can be defended based on analysis of historical climate change.” And further, it also ignores natural variation which is important because “natural processes have the potential to counteract or amplify the impacts of any manmade warming.” (I’m sure the “amplify” bit could have been downplayed even better with a more thought.)
** It sounds a far more “moderate amount of warming” if it is, as presented here, given as relative to 1985-2005 temperatures.
Thus this work by Judith Curry which says it provides “a rationale … for distinguishing between the conceivable worst case, the possible worst case and the plausible worst case, each of which plays different roles in scientific research versus risk management” [although I fail to see that it does provide such a rationale] could end up concluding that the Paris Accord’s +1.5ºC is achievable by following RCP6.0.
And that, children, is how Alice arrived in Wonderland.
Nemesis: Over & out.
AB: I do believe that that’s their goal.
@Al Bundy, #179
When I talk about extreme drought in Europe/Germany, all I get is Hate in my area. When I talk about insect die-off, all I get is Hate. When I talk about birds die-off, all I get is Hate. When I talk about dying trees, all I get is Hate all my life. The sheeples hate the message and they hate the messengers, they hate facts, they hate reality. It’s just surreal. I’m sick and tired of being the splinter in their brain, I’m sick and tired of Hate. I love being in solitude, I love to remain silent ever more. You know, greed, hate and ignorance, that’s just Samsara, it’s the way it is, this is reality.
MAR @178 says “The argument runs that RCP8.5 is dependent on assumptions on economic growth, population growth and fossil-fuel use that are collectively “borderline implausible.” (Ie higher than Judith Curry thinks will happen)
Judith Curry is too quick to claim that assumptions on population growth and economic growth are borderline implausible. Estimates of what would happen with population and economic growth this century vary widely, with the best estimate is slowdowns this century would be modest. Refer “Projections of population growth” on wikipedia. We might hope that population growth will slow down faster than this, but there is no guarantee it will and it would be foolish to assume it will, so RCP 8.5 is certainly plausible.
Economic growth is hard to predict with any certainty. There is a good argument and some evidence that it is already slowing in western countries, and is environmentally unsustainable, but countries are ingenious at prolonging economic growth, for example China, and much will depend on how AI and robotics develop. Its hard to be sure so RCP 8.5 looks plausible. This is not to say that endless economic growth is possible or desirable, simply that it may not slow down as fast as Judith Curry seems to think
“Of particular note is the continued extensive use of coal. Now, if you tot up the FF emissions within RCP8.5 from today to 2100, they do total 1,700Gt(C) and FF reserves stand today at 1,200Gt(C) with two-thirds of that coal. If the reserves remained at that level then, even with a return to extensive coal-use, RCP8.5 looks a tad unattainable. Except FF reserves of oil and gas both expanded 50% in 20 years (1995-2015). If that rate continues, there will be well-enough to attain RCP8.5, and that without any skyrockety additions to atmospheric CO2 which would be an incredibly serious worry under RCP8.5.”
It’s not clear how the fossil fuel estimate is derived, but a quick look at peak coal and peak oil on wikipedia shows estimates vary hugely and there is no consensus, so optimistic estimates are plausible , and thus so is RCP8.5. Its notable that the experts didnt really see the fracking boom coming. Of course we will run out of coal sooner or later in a few centuries at most, that is a given, I’m not minimising that problem, but it would be foolish to claim with certainty it will be this century.
Further to #73 in he August UV thread,
I have updated the graph of projected future MLO CO2 increases (usually 2 clicks to ‘download your attachment’) to include a provisional value for August’s MLO CO2 increase. It has come in with embarrassing accuracy as we should expect a significat bit of noise within the outcome (thus the ‘smoothed’ values tabled below).
And there is a little bit of ‘slight-of-hand’ in the modelling so the future CO2 increases were not projected with any great confidence.
The NOAA monthly Global CO2 are subject to significant revision in the months following first release which will modify the ‘modelled’ values but to prevent any resulting confusion I have here stuck with the global dCO2 values as released in July (these values up-to-&-including April) and 2.5ppm/yr for months thereafter. The modelled numbers graphed are tabluated below. (The average MLO modelled increase for the full callendar year of 2019 works out at 2.86ppm/yr.)
MLO 12-Month CO2 increases: Actual & Modelled.
…… ……. …. Actual … . (Smoothed) … Modelled
Jan19 … … … 2.87 … … … 2.85 … … … 2.74
Feb19 … … … 3.43 … … … 2.95 … … … 2.92
Mar19 … … … 2.56 … … … 3.02 … … … 3.13
Apr19 … … … 3.08 … … … 3.02 … … … 3.10
May19 … … … 3.42 … … … 3.21 … … … 3.16
Jun19 … … … 3.13 … … … 3.20 … … … 3.24
Jul119 … … … 3.06 … … … 3.05 … … … 3.07
Aug19 … … … 2.97* . … … … … … … … 2.94
Sep10 … … … … … … . … … … … … … 2.78
Oct19 … … … … … … . … … … … … … 2.66
Nov19 … … … … … … . … … … … … … 2.44
Dec19 … … … … … … . … … … … … … 2.13
Jan20 … … … … … … . … … … … … … 2.07
Feb20 … … … … … … . … … … … … … 2.06
Mar20 … … … … … … . … … … … … … 1.87
* provisional
Hurricane Dorian has now been upgraded to Cat 5 and it looks like the 2019 Atlantic Hurricane season, after the slowest start in twenty years, is entering a period of activity. As well as Dorian, there are three potential further tropical storms being tracked by the NOAA National Hurricane Center.
Could we be in for a repeat of the 2017 hurricane season when a crazy six week period from Sept to mid-Oct saw eight hurricanes with six of them major ones?
Items linked in the Aug 30 Science Advances notification:
Opinion cascades and the unpredictability of partisan polarization. From the abstract:
It sounds like when we’re in public fora, we should keep emphasizing the non-partisan character of the climate science consensus. Alrighty, then 8^}!
Also, The public and legislative impact of hyperconcentrated topic news:
Huh.
CO2?
August 18 – 24, 2019 409.57 ppm
August 18 – 24, 2018 406.90 ppm 2.67 ppm over last year
August 18 – 24, 2009 385.71 ppm 23.86 ppm over ten years ago
Noisy weekly numbers, but decadal look reduces noise somewhat.
Tamino has a post up about methane.
https://tamino.wordpress.com/2019/09/01/methane-acceleration/#comment-105194
“There was a time — from about 1999 until 2007 — when atmospheric methane wasn’t increasing at all. It had been, before 2000, but it remained steady for that 8-year period. But in 2007 it started rising again, as is plain to see in the following graph. What is not plain to see is that around 2014 it started rising even faster; the years 2014 through 2018 saw very rapid increase in CH4 levels…
Nisbet et al. identify the increased rate of rise in those four years, and consider the implication for the Paris climate agreement. The stated goal is to keep global temperature rise “well below 2°C.” So far, all our plans, our computer models, our strategies that have a decent chance of accomplishing that goal have relied on no increase in CH4, some even rely on decreasing CH4 in the air. The fact that it’s going the wrong way, at increasing speed, is a genuine threat to our chances of success…
What’s the source of the increase? One clue is the 13C/12C isotopic ratio, which has been decreasing lately. Fossil-fuel CH4 is usually “heavier” (i.e. higher in 13C than other sources) while microbial CH4 (from biological sources) is lighter. But we don’t have enough geographical coverage of 13C/12C isotopic ratio to nail down the source of that change. Nonetheless, Nisbet et al. speculate on several possible causes of the acceleration of atmospheric methane.
One possibility is an increase in microbial CH4, from wetlands and cattle, which would account for the atmosphere’s decreasing 13C/12C ratio. Another possibility is a change of the fossil-fuel mix toward natural gas, which has a lighter 13C/12C ratio than coal. Yet another possibility is a decrease in the atmosphere’s ability to break down CH4, which would likewise account for both the increased amount, and the decreasing 13C/12C ratio. The most worrisome possibility — although not yet a likelihood thank goodness — is a dramatic increase in microbial CH4 from permafrost melt or other feedback sources.
And of course we cannot rule out the possibility of “all of the above.” ”
Mike says: I think it is all of the above, but it’s very hard to nail this down with great certainty. When we know that the worrisome possibility of methane increase from permafrost melt and/or other feedback sources has become a certainty we will be hard pressed to reverse these sources and the warming that they bring.
I don’t see much good news in the methane increase story. Even if most of the methane increase could be attributed to the US fracking industry, there is no reason to believe that we can do anything about that. I will note that the Trump administration has moved to reduce regulation of methane leaks from industry. Unring that bell. The only good thing to say about methane is that it is relatively short-lived in the atmosphere.
No worries. The planet has an amazing ability to bring forth living things and the living things evolve. Many of the non-living things change over time. So, the deck is always getting shuffled. We don’t get to stop the game. Ante up.
Cheers
Mike
Martin Barlow:
Bummer. Winston Churchill is credited with “A lie gets halfway around the world before the truth has a chance to get its pants on.”
Not unexpectedly, it seems Jonathan Swift preceded him (my italics):
“Besides, as the vilest Writer has his Readers, so the greatest Liar has his Believers; and it often happens, that if a Lie be believ’d only for an Hour, it has done its Work, and there is no farther occasion for it. Falsehood flies, and the Truth comes limping after it; so that when Men come to be undeceiv’d, it is too late; the Jest is over, and the Tale has had its Effect…”
Apparently, t’was ever thus. It only hurts when I laugh 8^|.