This month’s open thread on climate topics. Try to be constructive!
Reader Interactions
34 Responses to "Unforced Variations: Sep 2024"
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Don Williams says
Meanwhile, back at the Ranch:
https://finance.yahoo.com/news/vp-harris-as-president-i-will-not-ban-fracking-165710122.html
rob davies says
Yet another indication on the critical nature of the cultural question. I have no doubt Harris and her team understand the situation with climate. Yet there is considerable evidence to suggest that promising a fracking ban will cost her the election.
If we are to be governed by some version of democracy and meet the climate threat, we’re not yet were we need to be with mass public understanding
Kevin McKinney says
Exactly so. And it may not even be in this case driven by national opinion, but rather by the public’s view in the swing state of Pennsylvania–in quite a few scenarios, as I understand it, the election could potentially turn on the result there. And a fracking ban is not popular in Pennsylvania.
(For readers not so familiar with the political landscape here, the US elects Presidents indirectly, via an 18th-century institution called the “Electoral College,” in which each state is allotted a specific number of electors based on population. State officials conduct the election according to their state’s laws; almost all use a winner-takes-all system by which all the state’s electors are pledged to vote for the candidate who received the most votes. In today’s landscape, a few states–so-called “swing states”–are closely competitive, and thus receive much attention and effort from both sides, as they are quite likely to be decisive. Pennsylvania (Harris +0.5 this morning) is one; the others generally considered as such right now are Arizona (Trump +0.5), Nevada (tied), Georgia (Trump +0.2), North Carolina (Trump +0.6), Wisconsin (Harris +1.4), and Michigan (Harris +1.1). All numbers are poll averages aggregated by RealClearPolitics. For the country as a whole, Harris is currently leading by 1.8%–a value that has been steady since last week. To our shame as a nation, this election is very, very close–margin of error of these polls is typically about +/- 3%.)
David says
Kevin, you’re right about Pennsylvania. The whole thing is going to come down to Pennsylvania. If Harris wins the state, the probability is high of her maintaining the “blue wall.” If she loses the state, the probability of her replacing those 19 electoral votes via some combination of sunbelt states is depressing very low.
Given how battleground state polling has under-polled Trump votes in 2016 & 2020 (a polling issue that the pollsters admit they’ve no reasonable certainty has been corrected), the warning signs are flashing brightly. When the Harris campaign says they’re currently underdogs, that’s accurate. Whom ever is guiding her economic messaging is doing her a disservice, it’s killing her chances of winning.
Nigelj says
From last months UV thread posted by CJ on 1st September: Holly Buck says (my paraphrasing) that people are genuinely worried about whether renewables will work, and that we should listen and not claim their concerns are all all a result of denialist missinformation / disinformation, and that we should do something about addressing their concerns. This sounds right in principle, because many people would have had these thoughts because they are natural concerns (although some people might have raised the issues after reading denialist websites). And if we say the general publics concerns are a result of missinformation, they might prefer to believe the missinformation, because this is easier than admitting to themselves they were fooled.
However millions of words have already been written in many forums answering questions about renewables and showing problems are over stated, and all this based on careful peer reviewed studies and experts views and without referencing denialist views. Despite this some people refuse to accept that renewables are the best solution overall. You can lead a horse to water….But fortunately polling shows the majority of people support renewables:
https://www.pewresearch.org/science/2023/06/28/majorities-of-americans-prioritize-renewable-energy-back-steps-to-address-climate-change/
https://www.renewableuk.com/news/672538/Polling-shows-strong-support-for-pro-renewables-policies-as-RenewableUK-launches-manifesto-.htm
Paul Pukite (@whut) says
It looks like Escobar has hijacked the discussion, but he made the crucial admission of defeat by stating: “which is clearly a lie / disinformation because “renewables” are NOT ETERNAL”.
https://pbs.twimg.com/media/GIqrYFbXMAANUk6.jpg
Anybody see why one must not talk about Fight Club?
Escobar says
Housekeeping to clear up other people’s confusions
[Response: Seriously, what are you even talking about? What new physics do you think we have invented? Radiative transfer? Conservation of energy and mass? Heat capacity? Navier-Stokes? Stefan-Boltzmann? Henry’s Law? Thermal expansion? Seems like pretty standard stuff to me… – gavin]
Yes, you don’t understand so try reading it again – it is you not me at fault here https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/comment-page-2/#comment-824223
If you wanted to understand what I was talking about you could. It’s not complicated nor a trick. I’m not talking about any “new” physics, I never used that term, so why did you strawman me?
I was obviously speaking to THE different physics of different drivers/forcings that produce past and present climate change. The same as climate scientists and the IPCC address such things all the time when trying to explain what THE PHYSICS of Different Forcing over Time and Space are behind climate science is all about in the past VERSUS the present and the future.
Yes, THE PHYSICS of the pattern of regular Ice Ages across Millions of Years is NOT THE PHYSICS of the forcing producing global heating and climate change today. It is a different dynamic – it is not new physics – it is a different kind of Physics in play forcing heating and climate change responses.
I say that as per the IPCC reports and climate research papers.
And that is still changing faster than the climate models and the research papers can keep up with. Obviously, or you would have known what was happening in 2023 during or before 2023.
Climate scientists know the physics of meteor hits and flood basalts and variations in orbits and insolation and continental shelfs (everything) were forcing and produced a paleo / ice ages climate very different from the physics of shipping sulfur emissions, the sea level and land use, the amoc, the volume of global ice that are forcing and impacting the climate dynamics of today.
I repeat, if you, Radge or anyone else wanted to understand what was being said then you could. You appear to chose not to.
…………………….
and then Radge — – was addressed to CJ.
I have thought and/or said almost the exact same things about this aspect (was it posted?) and wasn’t paying proper attention, Mea culpa for being ‘confusing’ this time. 1 time out of a 100 isn’t a bad result.
But I can’t compete with your wild judgements about ‘why” X happens so make up your own as usual. You’ll never believe me anyway because you do not care in the least.
Escobar says
FOR Radge: Quoting
Escobar says
30 Aug 2024 at 5:59 PM
https://www.realclimate.org/index.php/archives/2024/08/oh-my-oh-miocene/#comment-824178
Anyone suggesting global heating can be stopped by unfounded unproven net zero theories (opinions & beliefs) and the proposed ‘actions’ globally by 2050 is overtly saying:- “global heating is no big deal” – if it is that easy and so quick to stop.
Beliefs like this are much closer to schizophrenia delusions than a science based material reality.
Good paper ref. It is obvious and undeniable what is happening today is nothing like what happened in the past (causes and outcomes) and is orders of magnitude faster.
As well as totally out of control with a body of climate science unable to explain what is happening and what is coming with any degree of intelligent physics based logic or certainty.
Barton Paul Levenson says
E: Anyone suggesting global heating can be stopped by unfounded unproven net zero theories . . . Beliefs like this are much closer to schizophrenia delusions than a science based material reality. . . . climate science unable to explain what is happening and what is coming with any degree of intelligent physics based logic or certainty. . . .
BPL: This is just insults, slander, and name-calling. If you can locate a specific error, spell it out. Show your work.
Or STFU.
Kevin McKinney says
…and that would be flatly false. There are certainly many uncertainties remaining, but the big picture is very, very clear.
Nigelj says
Escobar, there is no such thing as physics based logic. If you feel you have to post wild inflammatory, incorrect, evidence free trolling rants at least get the terminology right.
Escobar says
For Radge and Gavin – everything is connected, what I post now is connected to what came before – on this forum. If you wanted to understand what I and others are talking about, you could. But you choose not to understand and then blame others for what you do not know or remember.
Karsten V. Johansen says
29 Aug 2024 at 9:51 AM
https://www.realclimate.org/index.php/archives/2024/08/oh-my-oh-miocene/#comment-824109
The reasons for this is obvious: over millions of years other external factors like plate tectonics, changing volcanism etc. play a bigger role, difficult to quantify.
The main characteristic of our human “global climate experiment” is that we are changing the tropospheric greenhouse gas content *at least an order of magnitude – ten times or more – faster than during any known comparable event from the whole geological history*, fx. the end permian basalt volcanism creating the siberian traps 252 m. yrs BP and the PETM 56 m. yrs BP.
This means that we should not only be extremely reluctant continuing along this path, in fact we would be better off, the sooner we manage to put an end to this global experiment, which was unconsciously startet by our ancestors a couple of hundred years ago.
Our climate models of course may all be very sophisticated mathematically etc., but they clearly have this serious weakness: because our “experiment” lacks parallels in the geological history, we really can’t calibrate the model results with anything known. Compared to the reality our models are indeed very simplistic.
…………………………….
Some people are allowed to use the word uncertainty, while others are not and automatically condemned as “deniers” or climate science illiterates.
From late last month
1 Sep 2024 at 3:11 AM
Obsessing Over Climate Disinformation Is a Wrong Turn
By Holly Buck
Much of the climate movement is now pouring its energies into combating disinformation. But this focus fails to address real concerns about a green transition and obscures what is needed to win the public over to effective climate action.
from https://jacobin.com/2024/08/climate-disinformation-green-transition-workers
The people who really need to act on this info / research will not read it, and if they do I suspect they will not know what it is talking about!
Barton Paul Levenson says
E: Our climate models of course may all be very sophisticated mathematically etc., but they clearly have this serious weakness: because our “experiment” lacks parallels in the geological history, we really can’t calibrate the model results with anything known. Compared to the reality our models are indeed very simplistic.
BPL: The physics remains the same. And I doubt you are familiar enough with the models to call them simplistic. How much model code have you read?
jgnfld says
C’mon, BPL, Surely you know “THE PHYSICS” of forest fires set by people and those set by lightning are simply not the same???!!!
Escobar says
“I never suggested that the rate of change would somehow represent a change in (The Laws of) Physics! – was another example of me discussing these related issues on the Miocene page:
JCM says
30 Aug 2024 at 8:27 AM
The headpost article attempts to demonstrate that the climate sensitivity of the distant past, when including factors like solar forcing, topographic configuration, and minor trace gases, is directly comparable to today’s conditions, with a fast ECS estimated at only 3.5°C.
However, this could be misleading. Left unperturbed, the paleo Earth had total freedom in biogeochemical and biogeophysical response. As you noted, as the CO2 rose, it’s likely that life diversified, soils enriched, and nutrient cycling intensified.
Today, the situation is markedly different. As humanity artificially drives up CO2 levels, life is being drastically diminished, soils are actively eroded, and biodiversity is in sharp decline. This by direct ongoing intervention. This is the exact opposite of what occurred in the past. Today’s unnatural and unprecedented combination of rising CO2 and declining biosystems suggests that paleo climate sensitivity estimates may not be directly comparable to those of today. Alarmingly, this implies that today’s climate sensitivity is likely higher than in the past.
REPLY – Escobar says
30 Aug 2024 at 6:10 PM
https://www.realclimate.org/index.php/archives/2024/08/oh-my-oh-miocene/#comment-824179
Climate science keeps on saying and implying and suggesting that they know things they do not know. Then basing their recommendations out of the IPCC and other bodies based on this not knowing unproven guesswork and assumptions, guesses and opinions of the most outspoken who declare they are certain about things when they and the science is clearly uncertain and unproven.
Resulting in – “it’s ‘easy’ to stop global heating, just hit zet nero (sic) emissions by 2050 and the warming will be stopped! The UNFCCC agrees.” That isn’t science. Or real.
[end quotes]
There would be far less confusion if people read what had already be said and remembered it better and were better equipped “to connect the dots” and not rush to judgement. There would be far less posts required to FIX other people’s ERRORS and ignorance of what recently happened.
Paying attention in the first place, not making assumptions, and asking questions respectfully is a far better approach. Oh, did I mention this new article yet? I think maybe I did.
https://jacobin.com/2024/08/climate-disinformation-green-transition-workers
Barton Paul Levenson says
E: Climate science keeps on saying and implying and suggesting that they know things they do not know. Then basing their recommendations out of the IPCC and other bodies based on this not knowing unproven guesswork and assumptions, guesses and opinions of the most outspoken who declare they are certain about things when they and the science is clearly uncertain and unproven.
BPL: This is about the tenth time you have posted basically the same rant. You don’t seem to have any specifics to go with the charges you make. Until you do that, STFU. We’re tired of reading the same abuse over and over and over again.
Nigelj says
Agree with BPL 100%.
Escobar says
Another reference for good measure:
Mal Adapted says
29 Aug 2024 at 1:55 PM
https://www.realclimate.org/index.php/archives/2024/08/oh-my-oh-miocene/#comment-824116
We’re talking about changes occurring over millions of years. Species evolved and went extinct as CO2 concentrations in the atmosphere and oceans rose and fell. Continents were moving. The Antarctic Circumpolar Current formed.
Climate is changing orders of magnitude faster now. We know with more than adequate confidence that ~300 years of economically-driven (i.e. anthropogenic) transfer of fossil carbon to the atmosphere is the principal driver of the contemporaneous rise of global heat content.
[end quote]
Nothing I have said contradicts Mal, nor does he contradict what I said yet many have found “wanting” here.
As Weird as Trump!
David says
JCM, I’d read your comments to Tomáš in the August UV on the 30th and 31st regarding the land/soil’s part in the C cycle, mankind’s impacts upon them, and your views on climate change modeling choices (or lack of) regarding this piece of the cycle as continuation of your discussion with others here:
.
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824195
.
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824227
.
While working in the yard this afternoon, I vaguely remembered I’d come across the following I’ve linked below somewhere sometime. If you have time/inclination to look at:
.
https://climate.ec.europa.eu/system/files/2016-11/soil_and_climate_en.pdf
.
Does this “The Hidden Part of the Climate Cycle” document address (in whole, in part, or not at all) your position?
BTW, if you or someone else here was the original source for this item previously, please forgive my memory lapse. I’d do a little digging to see how/when I came across this, but frankly Im too tired and hungry :-)
JCM says
To David,
the article “The Hidden Part of the Climate Cycle” focuses exclusively on the biogeoChemical effects related to the carbon exchange and oxidation between land and atmosphere.
This is the framing of all types of ClimateSmart™ initiatives, driven by the narrowly defined climate science and associated CO2 politics of today.
This naive framing results in enrolling landowners into carbon trading schemes (scams?), incentives for planting carbon sticks, and spreading stony reactive materials.
It’s part of a broader effort to commodify landscapes and trade them on global financial markets – where CO2 is treated as interchangeable across continents and fully fungible in investment portfolios. In the process, landscapes are detached from the places and communities they support, and the enormous power of self-motivation is diminished. This is catastrophic from a local governance perspective.
My interests are primarily in the biogeoPhysical land-atmosphere interactions and related effects of desertification. By marginalizing these effects in the study of climates, conservation stewardship has become undervalued by several times.
Climate science still falls short of providing the comprehensive, actionable insights needed to address changing climates at any scale. The European Commission report only reinforces a biased perspective which seems driven more by financialization than the needs of communities.
cheers
David says
JCM,
Thanks for replying. Your advocacy in support of your position impresses. Not having a substantive grasp of the matter has lead me to pretty much refrain from engaging in the interesting “soil/land degradation, climate change, modeling etc) conversation here concerning your perspective thus far. That’s something I aim to rectify, at least a little, in time (a lengthy amount of time no doubt ;-) If for no other reason than to gain a further understanding of how things work. And perhaps be a better advocate for things I care a great deal about.
I had that item I asked about in my files and thought it was a place to start. Doing a subsequent google scholar search using different search terms has lead me to a number of works (many quite recent) that at first glance look like papers worth the efforts to study. If you have a recommendation, please pass it along.
Tomáš Kalisz says
In Re to David, 1 Sep 2024 at 9:12 PM,
https://www.realclimate.org/index.php/archives/2024/09/unforced-variations-sep-2024/#comment-824261
Hallo David,
I agree to JCM, 3 Sep 2024 at 9:58 AM,
https://www.realclimate.org/index.php/archives/2024/09/unforced-variations-sep-2024/#comment-824308 ,
that the role of soils and vegetation is much more complex than presented in the cited document “The Hidden Part of the Climate Cycle” .
As I focus on one aspect of this complexity only, namely on the relationship between hydrological cycle and global climate and on its coverage in present climate change mitigation policies, I can hardly add anything to the general complex perspective emphasized by JCM.
Nevertheless, I think that from my (much narrower) perspective, the cited document can serve as a good example of the prevailing approach, treating soils and terrestrial vegetation mostly as a “carbon sink” or “carbon source” and basically omitting their important role in climate regulation through their participation in the hydrological cycle.
Greetings
Tomáš
Mal Adapted says
CJ, quoting one Holly Buck last month: That’s because the focus on “climate disinformation” sets up a negative feedback loop. No one doubts that misinformation is often an issue in today’s politics, especially around climate. But instead of focusing on misinformation alone, we should think of the challenge of engaging the public with climate as a triangle with three points: misinformation, conflicts over values, and distrust of elites.
Ms. Buck said some wise things in her Jacobin piece. By definition, I’m one of the online climate commentariat, though not one anyone else listens to. I’m certainly not a politician, but I’m sure reminding Americans that their addiction to fossil carbon is the principal cause of global warming, that the warming is a predictable result of the free market’s propensity to socialize every transaction cost it can get away with, that only collective (i.e. government) action can decarbonize the US economy, and only by either taxing carbon, subsidizing renewables or regulating emissions, is a hard sell with the 28% who are still disengaged, doubtful, or dismissive of the inconvenient truth.
Conflicts over values? You’re referring to the values of resolute culture warriors who equate all collective action with Communism. They’ll never admit that climate change isn’t just a liberal preoccupation. Thankfully, we don’t have to persuade those people, we just have to outvote them! For the 57% of us “concerned” or even “alarmed” about climate change, the choice of whom to vote for is a no-brainer. Trump and the Republicans will return the US government to a state of denial, leaving the costs of anthropogenic global warming open-ended. Harris and the Democrats will try to enact stronger decarbonization policies, although those are as yet unspecified; why should the Democrats propose a plan to get us to zero emissions, when the Republicans will throw every obstacle they can in the way from sheer spite, and reverse any previous, painful progress when they regain office? I’ll settle for a series of market interventions until nobody wants to buy fossil carbon anymore. Let the market do the hard work. Meanwhile, more doubters become believers whenever weather records get broken again. I’m optimistic climate realists will soon have a solid majority. Then it will be time to talk about a long-term plan.
You and Ms. Buck are entitled to your opinions. But distrust of elites? How come the documented funding of decades of official denialism by carbon capitalists doesn’t piss off the dimissives, CJ? Maybe angrily calling out mercenary denial won’t win the upcoming elections, but denying denial won’t either. I take seriously Dark Money author Jane Mayer’s remarks about a book by another business journalist, tracing the history of the Koch family’s long-term profit maximization strategy (my bolding):
If there is any lingering uncertainty that the Koch brothers are the primary sponsors of climate-change doubt in the United States, it ought to be put to rest by the publication of “Kochland: The Secret History of Koch Industries and Corporate Power in America,” by the business reporter Christopher Leonard. This seven-hundred-and-four-page tome doesn’t break much new political ground, but it shows the extraordinary behind-the-scenes influence that Charles and David Koch have exerted to cripple government action on climate change.
Kevin McKinney says
Yes, yes, yes and again I say “yes.”
Please, all ye who pass by, reject false equivalencies and vote for the sanest climate policy on offer!
And organize, to the best of your ability, to encourage others to do the same.
Radge Havers says
Escobar,
Trivial jibber jabber with Portentous Intonations. You’re headed into Time Cube territory, Sparky.
MA Rodger says
UAH have posted for August with a TLT anomaly of +0.88ºC, that’s up on July’s +0.80ºC and the 14th ‘scorchyisimo!!! month in a row,
These TLT anomalies as not dropping like the SAT anomalies. UAH is still sitting at the “bananas” level reached in September last year, having averaged +0.90ºC Sept-Aug with the highest anomaly in April (+1.05ºC) and the lowest June (+0.80ºC). This bunch of “bananas” monthly anomalies sit head-&-shoulders above previous ‘scorchyisimo!!! months, (averaging a whopping +0.4ºC above their respective previous ‘scorchyisimo!!! month).
That’s a big gap.
UAH is not unique for TLT with these ongoing “bananas”. NOAA STAR (which is yet to post for August) shows a not-dissimilar situation with no dip in the anomalies, Sept-July anomalies averaging +0.78ºC (+0.89ºC max, +0.72ºC min) with an average headroom above previous ‘scorchyisimo!!! months of +0.33ºC.
MA Rodger says
To better illustrate this difference between SAT anomalies (which show a significant drop since the new year) & TLT anomalies (which remain high and even peaked since the new year), I’ve posted a graphic here (posted 3rd August). This TLT & SAT graphic plots 5-month rolling averages to smooth the data out and also it is repeated with NH & SH to demonstrate the declining SAT anomaly is solely a NH thing. It is actually a NH Land thing (as show in a graphic on the same web-page posted in the above link four graphic below, first posted 13th February). Previous El Niños have seen NH Ocean and SH anomalies running roughly steady before a drop in the last months of the year (a decline in their 5-month rolling aves starting with the July-Nov average).
And given all that, as with the “bananas” SAT anomalies of late last year, I’m still of the mind that these unusually high temp anomalies are all an amplified response to El Niño as was seen in 2015-16 but now super-amplified, this speculatively all due to increasing stratification of ocean temperatures.
The ERA5 reanalysis as per Climate Pulse is showing daily numbers which give a average August 2024 global anomaly of +0.71ºC, identical to the August 2023 anomaly and a small increase on the last few months (May-Jul run +0.65ºC, +0.67ºC, +0.68ºC) which together show little sign of continuing cooling. (The global graphic linked above plots these monthly global ERA5 anomalies to Aug.)
But note that the cooling post-2016-El Niño continued into 2018.
As for a multi-month wobble interrupting such an inter-year cooling, given the decline in global SAT so-far has pretty-much all been NH Land, and given there is an annual cycle buried in these NH Land anomalies (due to Oct-Dec warming at a significantly faster rate over NH Land prior to 2005) resulting in a NH Land wobble, and given that wobble is considerably lessened in La Niña years, and given the La Niña is struggling to appear this year: given all that, I can see the decline in global SAT would pause for a bit before the NH Ocean & SH begin strongly contributing to the post-El Niño cooling.
One measure at ClimatePulse I have been watching is the 60N-60S SST. This represents about 63% of the globe so is a big player in the global average. The 60-60 SST is cooling relative to 2023 as it did in previous El Niño years,
in that it dipped below 2023 levels mid-July. Whether it continues cooling and reverses the super-warming seen prior to July 2023 (but warming not in seen in previous El Niño) is yet to be determined.
Susan Anderson says
to our good colleagues: Do you all remember the way Ned Ward monopolized this comment section, attacking all and sundry, flooding the zone with information and claiming it was to the discredit of our excellent hosts and climate science in general, and that none of us understood or were good enough?
Escobar is doing something similar. It doesn’t matter from which point of the compass the flooding comes, it still stifles open discussion and interesting material relevant to the subject matter of Real Climate.
I strongly recommend that we not encourage him with detailed responses and back and forth, becoming ever more elaborate in call and response, but rather treat it with dignified silence.
David says
The annual “LAND-BASED WIND MARKET REPORT. 2024 EDITION” for the United States is out:
.
https://emp.lbl.gov/sites/default/files/2024-08/Land-Based%20Wind%20Market%20Report_2024%20Edition.pdf
.
For those unfamiliar with this annual report, this is a soup-to-nuts comprehensive (92 pages) analysis of the wind market in the U.S.
.
Recommend it to anyone with an interest in renewable energy (even though its focus is the U.S.).
Kevin McKinney says
Thanks, David. Interesting stuff.
Bruce Calvert in Ottawa says
I am very excited by the new DCENT dataset. https://www.nature.com/articles/s41597-024-03742-x
It uses a variety of new and improved approaches to constructing an instrumental temperature dataset, including using deck metadata to improve sea surface temperature datasets, using improved land temperature homogenization methods that account for temporal autocorrelation, and using an energy balance model to compare sea surface temperatures with land surface temperatures to better account for biases in sea surface temperature datasets.
Mal Adapted says
Hey, Russell: it’s your favorite Progressive social engineer!
Biden’s Top Climate Negotiator to Visit China This Week.
Here’s a gift link if you need one. You’re welcome.
Tomáš Kalisz says
To Kevin McKinney, referring to your post of 30 Aug 2024 at 2:52 PM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824170
Dear Kevin,
I read your post carefully, but have not understood several points therein, to that I subsequently asked a few questions on 31 Aug 2024 at 8:27 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824209
It was the very end of the previous month, so you might have overlooked them. Could you look thereon and clarify?
Greetings
Tomáš
Tomáš Kalisz says
In Re to Barton Paul Levenson, 1 Sep 2024 at 7:08 AM,
https://www.realclimate.org/index.php/archives/2024/08/unforced-variations-aug-2024/#comment-824236
Dear Barton Paul,
you commented on my sentence
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.
as follows:
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.
I would like to add that as much as I read the summaries of IPCC reports, I have a strong feeling that the land use was mostly treated from the viewpoint if (and if so, how) it influences grrenhouse gas absorption or release.
The second aspect which is treated quite frequently in IPCC reports is the influence of “land use” on Earth surface albedo.
As regards possible influences of anthropogenic interferences with land hydrology, it was so far only the summary of the sixth IPCC report where I found a short note that irrigation may be among forcings that cool Earth surface.
I have not found any evaluation how such human interferences with water cycle like landscape sealing and drainage could (or could not) contribute to the observed global warming in the IPCC reports yet.
As regards other climate parameters than global surface temperature, such as e.g. global precipitation and surface distribution thereof, I am afraid that even you will have hard time if you try to find any study about relationship between human interferences with land hydrology through land use on one hand, and these parameters of the global climate on the other hand.
Greetings
Tomáš