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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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How extreme was the Earth's temperature in 2023

Jan at 16:59 PM on 19 April, 2024

What was special about the warming in 2023 was, that it happened all in the last 6 months, so it was a much larger jump over these months then the mean values of 2023.

Further, only a moderate El Nino existed, so not too much warming came from here.

Reasons where:

SOx reductions amplified the marine heatwave signal across the mid-latitudes.

The El Nino in combination with a positive Indian Dipole - both lead to a larger heat release of the tropical oceans as a clear and strong circulation cell is supported over the tropical oceans due to the zonal temperature gradient.

Sea ice reductions around the Antarctic caused circulation changes that led to moist and warm air advection over Antarctica (strong effect on the warming as exceptional heat waves rocked Antarctica), as well as radiative effects of the sea ice reductions and heat release over sea ice-free areas.

Then climate warming warms the oceans now more than natural variability is often able to produce colder than normal SSTs - at one time only some ocean regions existed with colder than normal temperatures.

Then we had the vast expansion of marine heatwaves across the global oceans, especially across the mid-latitudes reaching a coverage of more than 40% in July.

The warmer-than-normal Oceans created a cloud feedback thereby increasing shortwave absorption (reinforces marine heatwaves).

From 2012 to 2016 we had a non-linear increase of moisture in the marine boundary layer caused by exceptional SSTs. The next jump will have happened in 2023 causing a water vapor feedback over large parts of the oceans to increase. And tropical moist air advection is causing marine heatwaves in the subtropics to mid-latitudes. So also here another feedback as more water vapor radiates longwave radiation back to the surface.

Further, we had during summer to autumn large areas where the soil-moisture-temperature cascade came into play producing these exceptional continental heat waves. It comes along with a cloud feedback.

Then we had the pattern effect of increasing temperature gradients in the oceans surface and continents which disturb the overlying circulation, often causing blocking patterns (also a reason for the marine heatwaves to build up)

Then we had towards autumn a heat release of the marine heatwaves across the mid-latitudes, as the atmosphere gets colder.

Last it have been possible that the oceans released heat from the subsurface that had built up. Across the mid-latitudes warm freshening water masses are accumulating under the surface as shallow as 150m depth. And these heat depots could have been tapped, as the jets speed up during winter, as the density gradient between the tropics and poles increases in the upper atmosphere while it decreases near the surface. More and stronger low-pressure systems due to increased shear are the outcome. And all these extreme low-pressure systems in autumn and winter across the mid-latitudes in 2023/24 could have tapped this subsurface heat depot. But now study here as this is new.

Main problem thou is the expansion of marine heatwaves, as they are feedback driven by global warming heating the oceans from the surface too fast (thermal stratification increases non-linear in the upper 300m of the oceans in various regions), in combination with the pattern effect which disturbs global zonal circulation with the result of more stalled high-pressure systems (low wind speeds are in most instances THE precondition for marine heatwaves too form besides thermal stratification and small mixed layer depth).

Last the warming of the northern latitudes can also be included in the factors driving global warming in 2023.

In short the warming of 2023 was feedback-driven by various system forcing each other into a heating mode with the systems of the oceans, atmosphere, and landmasses acting in unison! The exact series of which contributed to what extent to the heating science has to find out. But it would have to do it on a monthly basis!

The next jump will have devastating consequences as they become larger...

Here is my FB page, want now to make my own blog, as the experts lose the oversight and models will be increasingly wrong (the model spread is in my opinion a joke as it is way too large proving the uselessness of models)...

https://www.facebook.com/Erdsystemforschung/

All the best

Jan

p.s. we warm the oceans too fast that is our main problem!

2024 SkS Weekly Climate Change & Global Warming News Roundup #13

Bob Loblaw at 02:59 AM on 5 April, 2024

Gavin Schmidt has also posted about this over at RealClimate.

Much ado about Acceleration

In the concluding paragraph:

Remarkably, the Hansen et al projections are basically indistinguishable from what the mean of the TCR-screened CMIP6 models are projecting. 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)

Welcome to Skeptical Science

Bob Loblaw at 01:07 AM on 5 April, 2024

cookclimate @ 118:

I have looked at the paper in the volume I linked to in comment 121. There are definite changes compared to an earlier version I found that said "submitted to Earth and Space Science", so I presume that you've had some sort of review and modified the paper since the earlier drafts.

It looks like you have identified the 1470-year cycle using your eyecrometer. I see nothing in the paper that actually does any sort of signal processing to identify cycles using any objective statistical technique. You are seeing a cycle because you want to see a cycle.

Your speculation includes arguments that include all sorts of stuff that has been debunked many times before. Pages are available on Skeptical Science that cover thee topics:

Geothermal heat flux is included in this post.

The "CO2 lags temperature" argument is discussed here.

Most of your examples use regional, not global, temperature proxies. Regional temperatures are far more variable than global ones, and it is invalid to compare the two directly. This is discussed in this SkS post.

You're convinced that an increase in volcanoes are adding to warming. That is the opposite of the argument commonly made by "skeptics" that increasing volcanic activity caused the Little Ice Age, so a subsequent decrease is causing warming (discussed here). In any event, just counting the number of volcanoes (your figure 3) is extremely simplistic. Arguing that more volcanoes implies more geothermal heat is a non-starter, as discussed in the post linked above.

Your "computer models are unreliable" is an old, tired argument, scoring position 6 on the SkS Most Used Climate Myths. The rebuttal is here.

So, your paper is really nothing more than an "I see it" 1470-year cycle mixed with a rehash and Gish Gallop through a variety of common "skeptic" myths. I could probably find more, but it isn't worth the time.

I hope you didn't pay too much money to get it published.

Climate - the Movie: a hot mess of (c)old myths!

scaddenp at 06:38 AM on 3 April, 2024

Two dog. The OHC content data in red comes from the Argo array. You can find reasonable description here. The old pentadecadal data is ship-based and has much bigger error bars. I cant immediately find the paper that determined the accuracy of the Argo data but if interested I am sure I dig it out.

On interannual and to some extent the decadal scales, variations in surface temperature are strongly influenced by ocean-atmosphere heat exchange, but I think you would agree that the increasing OHC rules that out as cause of global warming?

"I did also read that the warming effect of CO2 decreases as its concentration increases so the warming is expected to reduce over time. Is there any truth in that?"

Sort of - there is a square law. If radiation increase from 200-400 is say 4W/m2, then you have to increase from CO2 from 400 to 800ppm to get 8W/m2. However, that doesnt translate directly into "warming" because of feedbacks. Water vapour is powerful greenhouse gas and its concentration in the atmosphere is directly related to temperature. Also as temperature rises, albedo from ice decreases so less radiation is reflected back. Worse, over century level scales, all that ocean heat reduces the ability of the ocean to absorb CO2. From memory, half of emissions are currently being absorbed there. Hot enough and the oceans de-gas. These are the calculation which have to go into those climate models.

Which brings us to natural sources. Geothermal heat and waste heat are insignificant so would you agree that the only natural source of that extra heat would be the sun? Now impact of sun on temperature has multiple components that climate models take into account. These are:
1/ variations in energy emitted from the sun.
2/ screening by aerosols (natural or manmade). Important in 20th century variations you see.
3/ changes in albedo (especially ice and high cloud)
4/ The concentration of greenhouse gases in the atmosphere.

Now climate scientist would say that changes to all of those can account for all past natural climate change using known physics. They would also say very high confidence that 1/ to 3/ are not a significant part of current climate change (you can see the exact amount for each calculated in the IPCC report). Why are they confident? If you were climate scientist investigating those factors, what would you want to measure to investigate there effects? Seriously, think about that and how you might do such investigations.

Is it possible there is something we dont understand at play? Of course, but there is no evidence for other factors. You can explain past and present climate change with known figures so trying to invoke the unknown seems to be clutching at straws.

Climate - the Movie: a hot mess of (c)old myths!

jimsteele at 06:07 AM on 3 April, 2024

A Netherlands journalist, Maarten Keulemans, tried to denigrate Climate the Movie: The Cold Truth in about 50 tweets using much of the same arguments posted to here on SkepticalScience. I successfully debunked all of his arguments in 16 tweets (originally I intended 20) listed below, and so I was just honored with being interviewed for a Dutch TV segment regards how the Climate the Movie promotes vital scientific debate. Too often alarmists try to suppress debate with weak arguments or denigrating the opposition as deniers. However I doubt alarmists can refute any of my arguments, but I will gladly entertain your arguments.

1 Denigrating the Climate Reconstruction graph by Ljungqvist https://twitter.com/JimSteeleSkepti/status/1771929435366940908…

2 Keulemans' Medieval Warm Period lie https://twitter.com/JimSteeleSkepti/status/1771933673488789868…

3 Contamination of Instrumental by Urbanization https://twitter.com/JimSteeleSkepti/status/1771939656504062260…

4 The Best USA temperature Statistic! https://twitter.com/JimSteeleSkepti/status/1771947116631580724…

5 Ocean Warming Facts https://twitter.com/JimSteeleSkepti/status/1771957182407536940…

6 US Heat Waves https://twitter.com/JimSteeleSkepti/status/1771963700951527487…

7 It is the Sun Stupid! https://twitter.com/JimSteeleSkepti/status/1771977013576024282…

8 Alarmists know better than Nobel Prize Winners ! https://twitter.com/JimSteeleSkepti/status/1771987039631921454…

9 Wildfires: Liar Liar Keulemans' Pants on Fire https://twitter.com/JimSteeleSkepti/status/1772000151596572844…

10 The Dangers of CO2 Sequestration and CO2 Starvation https://twitter.com/JimSteeleSkepti/status/1772016867265380795

11 Models Running Hot! Keulemans Disgraceful attack on the most honest Dr John Christy! https://twitter.com/JimSteeleSkepti/status/1772081300884852829…

12 Keulemans’ Blustering Hurricane Fears
https://twitter.com/JimSteeleSkepti/status/1772319957042479298

13. Dishonestly Defining Natural Climate Factors
https://twitter.com/JimSteeleSkepti/status/1773395443864736058

14. Denying Antarctica’s Lack of Warming
https://twitter.com/JimSteeleSkepti/status/1773473481637957758

15. Misinformation on CO2’s Role in Warming Interglacials during our Ice Age.
https://twitter.com/JimSteeleSkepti/status/1773777313924297210

16. Science journalists vs grifting propagandists – Antarctica
https://twitter.com/JimSteeleSkepti/status/1774428539858907444

A data scientist’s case for ‘cautious optimism’ about climate change

Bob Loblaw at 00:26 AM on 3 April, 2024

lchinitz:

Do you (or others) have a reason to think that such costs are not part of the economic analysis? Basic economics talks about "supply and demand", where consumption of a good will tend to decrease as prices rise. The rate of decrease in relation to the price increase is call "the elasticity of demand". A highly elastic demand (easy to avoid the purchase, or people just can’t afford it) results in a big drop, while a low elasticity (people buy anyway) results in a small decrease. (Maybe demand goes up if they increase prices, as far as I can tell with Apple.) Elasticity of demand on each product modelled would need to be specified as an input or constraint on the model.

(The supply side of "supply and demand" suggests that as prices rise, more people will be willing to produce and sell. The balancing point is when prices encourage enough producers to produce and sell to the number of people willing to buy at that price.)

Another common economic concept is "opportunity cost". Look! I got 3% this year by buying a GIC! Yes, but you lost 3% because you took the money out of another investment that would have produced 6%... There is a cost associated with the loss of opportunity that the 6% investment offered. This "which is better - mitigation or adaptation?" question appears to me to be essentially an "opportunity cost" question. Not a surprise to economists.

I don't know the internals of economic models, but I would expect that at least some (if not most) of the increased costs associated with climate action would cascade into negative impacts elsewhere, via implicit relationships such as supply and demand and opportunity costs. Even if there is not an explicit statement within the model or analysis, the concept is embedded as a result of other things explicitly included in the model.

Climate - the Movie: a hot mess of (c)old myths!

diff01 at 19:38 PM on 1 April, 2024

Will changing one small ingredient (0.04%) of the earth's greenhouse gases (CO2) arrest gloabal warming (if that is what is happening)?

If the scientists(?) believe this to be the case, how will it be regulated to adjust the climate to maintain an average that is not too hot or cold?

If all anti-carbon emitting policies were implemented, what says the climate will not be too cool?

The other, obvious hole in the argument for drastic economic change in the name of cooling the planet, is that the sun is not factored into the equation (by the way, I am all for increasing efficiency and reducing waste). How will the climate be regulated (say changing one greenhouse gas does the trick) if the sun's intensity changes (sun spots), the reduction in carbon emission works, and it cools too much?

Another question I have is about other factor's, such as the recent eruption at Hunga Tonga. Apparently water vapor increased by 10% in the stratosphere.

Won't that affect the climate? How do the 'models' account for nature not doing what the computers predict?

There are a myriad of other questions. I haven't watched the movie yet, but will, with interest.

When I searched for the movie, this website popped up right under the movie heading.

It's always interesting to hear from the 'true believers'.

The whole thing is a sham of biblical proportions. You need just a modicum of reasoned thought to tell you so.

Just had a quick look at your response regarding 'the sun'.

You say the 'irradiation level' has been measured with accuracy for the last 40 years, and shown little variation.

The sun has been influencing weather on earth for 4 and a half billion years. What about the earth's orbit, and it's distance from the sun?

Climate - the Movie: a hot mess of (c)old myths!

diff01 at 19:32 PM on 1 April, 2024

Will changing one small ingredient (0.04%) of the earth's greenhouse gases (CO2) arrest gloabal warming (if that is what is happening)?

If the scientists(?) believe this to be the case, how will it be regulated to adjust the climate to maintain an average that is not too hot or cold?

If all anti-carbon emitting policies were implemented, what says the climate will not be too cool?

Another question I have is about other factor's, such as the recent eruption at Hunga Tonga. Apparently water vapor increased by 10% in the stratosphere.

Won't that affect the climate? How do the 'models' account for nature not doing what the computers predict?

There are a myriad of other questions. I haven't watched the movie yet, but will, with interest.

When I searched for the movie, this website popped up right under the movie heading.

It's always interesting to hear from the 'true believers'.

The whole thing is a sham of biblical proportions. You need just a modicum of reasoned thought to tell you so.

Climate - the Movie: a hot mess of (c)old myths!

John Mason at 00:25 AM on 1 April, 2024

I like to enquire - of people who disparage models - whether they fly. A lot of computor modelling goes into aircraft design, so people so concerned about the performance of models would never, you'd think, fly again!

Climate - the Movie: a hot mess of (c)old myths!

Bob Loblaw at 00:07 AM on 1 April, 2024

Two Dog: You say ' but I am less convinced about the arguments that "all other causes for the current warming have been looked at and ruled out".'

First of all, I will point out that nobody here, and nobody in climate science (that I am aware of), has ever claimed that "all other causes ... have been looked at". In fact, I'd be willing to wager that there is not a single scientific subject where any scientist would claim that "all other causes ... have been looked at".

By putting that phrase in quotes (in your statement in #41), you are making it look as if someone has actually made that claim. If you have a source for such a quote, please provide it. Otherwise, you are creating a strawman argument, and setting impossible expectations ("all other causes").

In the rest of comment 41, you are basically making an argument from incredulity. You use strawman terms such as "all of those factors", and emotive impossible expectations such as "then accurately measure their hypothetical potential impact". You throw in rhetorical questions such as ' how do we "know" what would have happened to our climate absent human GHG increases?'

The answer to the last question is, climate scientists do the science. The second figure in my comment 34 shows the results of some of that science: running models that look exactly at the question you raise - how does the model behave with and without the anthropogenic forcing. They look at hypothetical natural and anthropogenic causes, quantify them as best they can, and perform calculations to determine the relative importance of each factor.

As Eclectic pointed out in comment 31, saying there might be some "undiscovered mysterious physical cause responsible for the recent rapid global warming" [Eclectic's words] is nothing but handwaving. Unless you can propose a plausible mechanism that would cause the warming (and another one to offset the warming from GHG, as Eclectic points out in #31), then you're just blowing smoke.

People often try to use the same bogus arguments in denying that fossil fuel combustion is causing the rise in atmospheric CO2. They postulate some mysterious, unknown source of CO2 that remains undiscovered - and avoid the question of what mysterious, undiscovered process is managing to remove all the CO2 from fossil fuels (but can't remove this mysterious, unknown source of CO2 that is making atmospheric CO2 rise).

You may as well be saying "it could be fairies".

...and before you try to counter the graphical evidence in the figure I posted in comment 34 using the "but modelz" argument, I will point out that everything in science uses models. Descriptive, mathematical, statistical, computer simulations - all are different forms of models. If you don't accept models as valid science, then you are rejecting science writ large. (The original post points out that reliabilty of models is one of the myths that was raised in the movie, and proves a link to the SkS page that covers this myth.)

Skeptical Science New Research for Week #12 2024

nigelj at 06:05 AM on 22 March, 2024

Regarding "Climate models can’t explain 2023’s huge heat anomaly — we could be in uncharted territory, Schmidt, Nature [perspective]:"

This is very concerning and perceptive.

This following article by Copernicus has a great review of the effects of aerosols, and some interesting ideas of what may have contributed to last years unusually high temperatures in the nothern atlantic in partcular:

"Aerosols: are SO2 emissions reductions contributing to global warming?"

https://atmosphere.copernicus.eu/aerosols-are-so2-emissions-reductions-contributing-global-warming

Excerpts:

In 2020, the International Maritime Organization adopted its ‘IMO 2020’ regulation to drastically reduce shipping-related sulphur dioxide (SO2) emissions. Studies have concluded that the drop in emissions significantly reduced the formation of clouds over shipping lanes. An analysis by Carbon Brief estimated that that “the likely side-effect of the 2020 regulations to cut air pollution from shipping is to increase global temperatures by around 0.05C by 2050 (My note: Clearly this doesnt do much to explain the last 9 months unusual warming, and why would a change in 2020 shipping fuels that was implimented in that year, not slowly phased in, suddenly manifest 3 years later anyway? ). This is equivalent to approximately two additional years of emissions.” However, linking SO2 reductions directly to the recent extreme marine heatwaves omits part of the complexity of using models to calculate sulphate aerosol interactions in the atmosphere or estimating the effective application of the IMO 2020 regulation, and, more generally, the complexity of climate and atmospheric chemistry.

Reviewing the record North Atlantic Sea surface temperatures in June 2023, a preliminary analysis from CAMS scientists found a significant negative anomaly in Saharan dust aerosol transport over the tropical Atlantic Ocean, and an increased anomaly in biomass burning aerosol over the North Atlantic, coming from the massive Canadian wildfires. These aerosol anomalies are much bigger than the sulphate change from shipping emission reductions. This makes the estimation of the impact of reduced sulphate aerosol emissions on the sea surface temperatures very challenging.

June 2023 monthly mean aerosol optical depth (AOD) anomaly relative to June average AOD for the period 2003-2022 from the CAMS global reanalysis of atmospheric composition shows a negative anomaly related to reduced dust transport across the tropical North Atlantic (blue) and a positive anomaly related to smoke transport from Canadian wildfires over the extra-tropical North Atlantic (red). Base on non-validated data Credit: CAMS

The Copernicus Climate Change Service (C3S) also suggested that, among other factors, the reduced winds of a weakened Azores anticyclone - an extensive wind system that spirals out from a centre of high atmospheric pressure - could have reduced the ocean-atmosphere exchange and the vertical mixing of the ocean between colder and warmer waters, as well as reducing Saharan dust transport over the Atlantic, all of which has the potential to increase the ocean surface temperature.

“There will be, no doubt, long-term impacts from the reduced SO2 emissions, but it will demand dedicated research to understand the impact of sulphur changes. The changes in dust or black carbon have a more tangible effect in the short term”, says Richard Engelen CAMS Deputy Director.

My comments: Of course this doesn't easily explain the unusually high levels of warming in the pacific. Next year will be revealing. It should be relatively cooler year on past patterns but if it isnt IMO it would suggest a step change in anthropogenic global warming. We know the climate is non linear and abrupt changes are possible. Will be interesting to see what BS the denialists will come up with to counter another unusually warm year.

It's a natural cycle

Paul Pukite at 08:51 AM on 21 March, 2024

As per the latest observations, nothing is ruled out

https://www.nature.com/articles/d41586-024-00816-z

"Climate models can’t explain 2023’s huge heat anomaly — we could be in uncharted territory" :

Taking into account all known factors, the planet warmed 0.2 °C more last year than climate scientists expected. More and better data are urgently needed.

By Gavin Schmidt

Is Nuclear Energy the Answer?

michael sweet at 00:24 AM on 24 February, 2024

John ONeill:

You link to a Nuclear Energy Agency report, hardly an unbiased source, that contains no data or analysis. They link to an IPCC report where the summary for policy makers alone is 24 pages long. The report is hundreds of pages. You must provide a link to an evidence based report and give me the pages that relate to the topic we are discussing. Most proposed future energy systems have a little nuclear since plants currently under construction will presumably still be running in 26 years.

Your other link, which I have previously debunked upthread, is a web piece by a completely uninformed person who has no education or experience in nuclear energy and learned everyting they know about nuclear from the internet. (If you read the rest of this thread you would stop repeating the mistakes nuclear supporters have made upthread). He models the current electrical supply in the USA. Since all cars and all heating by heat pumps will be electrical it is expected that electrical consumption in the USA will at least double. His system is much too small. He uses fossil gas for storage since the required storage would be too expensive to build. I note that a system using fossil gas for storage does not stop emitting CO₂ as required. Duh! The cost is prohibitive, he assesses cost incorrectly. The ignorant errors in this analysis are too numerous to address. The fact that nuclear supporters cite this blog proves that nuclear is not economic.

Do you really want to run Afganistan and Yemen completely on nuclear? A solution that does not work for most of the world is hardly a reasonable proposal. There is only enough uranium in all known deposits to run the entire world for 5 years. (Abbott 2012). Read Abott 2012 (linked in the op).

Here is free link to the Jacobson et al 2022 paper titled "Low-cost solutions to global warming,air pollution, and energy insecurity for145 countries". Note that Jacobson describes a solution suitable for the entire world and not just the USA. Upthread I have provided at least a dozen links to free papers that describe completely renewable systems to generate all energy for the entire world. If you read Jacobson you will have more knowledge of what we are talking about. You currently are not very informed.

Here is a free link to a paper titled "On the History and Future of 100% Renewable Energy Systems Research", one of the 59 papers that have cited the Jacobson paper. If you read it you will be more informed about what energy researchers think about future energy systems and make fewer ignorant statements online.

If you have not put in the work to learn how to find papers that support your position it is not my problem. It is not my job to spoon feed you information that you cannot be bothered to read yourself. You have to do your homework if you want to tell other people what they should do. Uninformed proposals do not help advance the discussion.

The fact that you cannot find anything to support your position demonstrates that the nuclear discussion on line is completely fantasy based and not fact based. If documents supporting the nuclear position existed than nuclear supporters would cite them. Nuclear supporters cite industry propaganda as if it were fact based information.

Whenever I examine nuclear supporters claims closely I find that they are not supported by the data.

Nuclear is not economic, takes too long to build and there is not enough uranium.

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

Bob Loblaw at 02:38 AM on 14 February, 2024

In the RealClimate post that scaddenp links to in comment 9, Gavin Schmidt makes specific reference to that Spencer claim that climate models do not conserve energy. Schmidt states:

Do climate models conserve mass and energy? Yes. I know this is be a fact for the GISS model since I personally spent a lot of time making sure of it. I can’t vouch for every single other model, but I will note that the CMIP diagnostics are often not sufficient to test this to a suitable precision – due to slight mispecifications, incompleteness, interpolation etc. Additionally, people often confuse non-conservation with the drift in, say, the deep ocean or soil carbon, (because of the very long timescales involved) but these things are not the same. Drift can occur even with perfect conservation since full equilibrium takes thousands of years of runtime and sometimes pre-industrial control runs are not that long. The claim in the paper Spencer cited that no model has a closed water cycle in the atmosphere is simply unbelievable (and it might be worth exploring why they get this result). To be fair, energy conservation is actually quite complicated and there are multiple efforts to improve the specification of the thermodynamics so that the models’ conserved quantities can get closer to those in the real world, but these are all second order or smaller effects.

Note that this statement from Schmidt is in a postscript added three days after the original post. At the top of the postscript, Schmidt states:

Spencer has responded on his blog and seems disappointed that I didn’t criticize every single claim that he made, but only focused on the figures. What can I say? Time is precious! But lest someone claim that these points are implicitly correct because I didn’t refute them, here’s a quick rundown of why the ones he now highlights are wrong as well. (Note that there is far more that is wrong in his article, but Brandolini’s law applies, and I just don’t have the energy).

This is not the first trip to the rodeo on Spencer's work of this sort. There is a pattern.

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

MA Rodger at 01:34 AM on 14 February, 2024

retiredguy @8,

The essay by Spencer is his usual mess of nonsense dressed up to look like an informed and reasonable account.

Note for instance his second "takeaway":-

Climate models that guide energy policy do not even conserve energy, a necessary condition for any physically based model of the climate system.

This is not a "takeaway" as such but a simply a bold statement supported only by reference to Irving et al (2021) 'A Mass and Energy Conservation Analysis of Drift in the CMIP6 Ensemble', a paper which does not in any way conclude that 'model drift' invalidates the findings of CMIP models as Spencer states it does. Here Spencer is very badly wrong but likely, as with his other egregious mistakes that happen to support his denialist views, he doesn't care and will not correct it.

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

retiredguy at 06:44 AM on 13 February, 2024

Any thoughts / comments on the below article by Roy Spencer ?

https://www.heritage.org/environment/report/global-warming-observations-vs-climate-models

Introducing an Atmospheric Radiation Model to Learn About Global Warming

Charlie_Brown at 07:52 AM on 11 February, 2024

Thanks. I would like to re-emphasize, as mentioned in the section "Model Versions", that the commercial version of MODTRAN was developed by collaboration with the U.S. Air Force and Spectral Sciences, Inc. MODTRAN is a registered trademark of the United States of America, as represented by the United States Air Force. Now in version 6, the commercial version is not free. It provides much more flexibility for research purposes than the educational version hosted by the University of Chicago. For this reason, I like to use the acronym MILIA (MODTRAN Infrared Light in the Atmosphere) to differentiate the two versions.

Increasing CO2 has little to no effect

Dominic68 at 00:09 AM on 3 February, 2024

I have had this publication and this one cited against me in argument. Has anyone come across them? Essentially they are being used to argue that C02 > 400ppm concentration will not trigger further heating.

Skeptical Science New Research for Week #5 2024

One Planet Only Forever at 15:59 PM on 2 February, 2024

Thank you for another informative and enlightening curated set of research reports.

I particularly recommend: How Economics Can Tackle the ‘Wicked Problem’ of Climate Change, Stiglitz et al., School of International and Public Affairs/Institute of Global Politics, Columbia University (from this week's government/NGO section)

The entire document is a relatively brief presentation. I am a fairly slow reader. And it only took me 40 minutes to read all of the document.

The following extracted points may encourage people to read the full document.

Introduction ends with:

This report describes how the tools of economics, when combined with insights from other disciplines, can help policymakers address tradeoffs, implement climate policies that are both equitable and cost-effective, and help the world achieve a more sustainable future.
The Conclusion ends with:

We cannot “optimize” climate actions with any useful precision by balancing the benefits and costs of action — understanding risk and uncertainty and the concomitant urgency of addressing climate change are central to climate policy. Carbon prices work best when combined with other policies to support the development of infrastructure, institutions, regulations, and alternative technologies. In addition, international treaties are most effective when they combine sticks and carrots to encourage deeper cuts in emissions over time while maintaining broad — if not universal — participation. As befits a “wicked” problem, we need to continue to learn from the past and adapt our strategies for reducing emissions as we go.

What I found particularly informative was in the section headed WHAT SHOULD BE THE GOAL OF CLIMATE CHANGE POLICY? The following quote is from the middle of the section:

A surprising source of fodder for the climate action naysayers has come from a group of economists who use models that generate so-called “optimal” pathways by attempting to balance the benefits and costs of climate action. While these models can be calibrated to show virtually any result, the versions that have received the most attention show that the “optimal” level of action would be to allow the earth to warm between three to four degrees Celsius by 2100 — a level of warming that most scientists say is truly frightening.4 Recent updates to the model suggest an optimal warming of 2.7 degrees in 2100.5

This level of warming is still high. Researchers at Columbia and elsewhere have investigated these models, called Integrated Assessment Models (or IAMs) because they integrate environmental effects with economics, something that all good models do. The assumptions ingrained in these models about the environment, the economy, and how they interact are badly flawed.

The section then elaborates on the flaws including the following selected quotes:

... while climate change is a threat multiplier that will affect societies in countless ways, damage estimates focus on the few effects of climate change that are easiest to capture. Many or most categories of climate damage — migration, conflict, ocean acidification, biodiversity loss, etc.— are not included in state-of-the-art models.

...the models usually ignore distributional concerns, which are highly relevant to policy responses because climate change has the greatest impact on the poor, who have the fewest resources to protect themselves.

Future generations will also be disproportionately harmed by climate change, and they are typically undervalued in IAMs as well. Indeed, a critical assumption in the IAMs is how future benefits are “discounted.” A dollar today is worth more than a dollar 100 years from now, but how much more? And how do we value the reduced risk of a climate catastrophe confronting our grand-children? Most climate damage estimates implicitly undervalue future generations by discounting future benefits using market rates of return, which are determined largely by the preferences of individuals today over consumption at different points during their lifetimes — thus failing to grapple with the ethical issues raised by taking on risks that will be borne by future generations.

More reasonably, and more ethically, we should value our children and grandchildren as much as we value ourselves. Consider a situation where climate change’s effects turn out to be particularly severe, which is a realistic possibility that most IAMs ignore. Incomes of future generations will be reduced as a result — but they will have to spend a lot to repair the damage and to adapt to the new climate, at precisely those times when they are least able to do so.

In addition to undervaluing the benefits of action, the IAMs do not provide useful estimates of the costs of climate action, in part due to the extreme difficulty of forecasting technological innovation over centuries. The models also assume that markets are perfectly efficient, or that they would be efficient if only we could get the price of carbon right — the only distortion is caused by green-house gas pollution. But, as we discuss further in the next section, research over the past 50 years has highlighted the multiple inefficiencies in market economies that serve as barriers to emissions reductions — imperfections of competition, of information, of absent markets, and ill-informed or less-than-rational individuals.

To be sure, the most recent studies have produced enormous improvements over earlier versions of IAMs. For example, an analysis by Danny Bressler of Columbia University shows a seven-fold in-crease in climate damages from incorporating an estimate of human mortality caused by temperature increases.9 The latest estimates from the U.S. Environmental Protection Agency now includes damages from temperature-related mortality.10 However, even the state-of-the-art estimates of climate damages are plagued by the same limitations noted earlier.

Skeptical Science New Research for Week #26 2023

Eclectic at 09:38 AM on 2 January, 2024

Just Dean @11 :

Yes, the Osman study shows a slightly different "shape" to the subsequent millennia following the Holocene Optimum of (very roughly) 7,000 years ago. And yes, that is of innate interest, but it makes little difference with respect to the rocket-like rise of global temperature which is progressing during the current industrial era.

In golfing metaphor, it is the consideration of how past holes were played . . . compared with where the ball is sited right now ~ and what we need to do playing the ball right now.

With or without climate models, we know enough about the angle of the grass slope & the wind's strength/direction, to make a reasonable judgement on how to strike the ball. Lack of Will, is our problem.

Skeptical Science New Research for Week #26 2023

Just Dean at 07:26 AM on 2 January, 2024

Eclectic @10.

I have been following Dr. Tierney's work for sometime. I think Dr. Tierney's work is underappreciated. I think the combination of proxy data with modeling is cutting edge for paleoclimatogy. For instance, I think her paper in Nature with Osman may ultimately redefine the shape of the "hockey stick," REF .

Also, look at the quality of the fit for the Cenzoic age, this research really might start to constrain the climate models for predicting future temperatures for different emission scenarios.

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

MA Rodger at 19:54 PM on 12 December, 2023

Dessler's post does rather hedge its bets by suggesting it might be "due to natural variability persisting over an extended period" which will at some point come to an end (so as per the 2007-12 slowdown but in reverse). But he also points to the recent deep La Niña which may be amplifying the impact of the less-than-massive El Niño.

The ENSO indices do show the build-up to present weak El Niño conditions were unusually preceded by strong La Niña cinditions which had been, if anything, strengthening through the period rather than, as is usual, weakening as El Niño conditions approach. (The MEI perhaps shows this situation best.) Yet the big 1997-98 El Niño also strengthened quite suddenly and showed nothing like this 2023 bananas situation.

MEI el nino profiles

The bananas (sudden appearance of an additional +0.2ºC in the global average temperatures) won't be some sudden forcing as there is no sign of anything (or things) approaching the required force. That means we have a natural wobble.

But is that wobble reversing something that has been shielding the impacts of AGW and so it won't reverse? Or is going to abate in coming months/years? Dessler looks to the climate models as suggesting it is the latter. But the question is still an open one!!

At a glance - Evidence for global warming

Paul Pukite at 07:31 AM on 7 December, 2023

You may be skeptical of the claims, but they're out there and after 5 years no-one has tried to refute, debunk, or falsify the claims. I submitted a presentation to next spring's US CliVar Workshop which they're calling "Confronting Earth System Model Trends with Observations: The Good, the Bad, and the Ugly".

Comparing historical trends in Earth system models with observations to identify and understand where models are performing well and poorly to focus the community on where more work is needed to ensure credible projections moving forward. What are we getting right? What are we getting wrong and why? What have we not yet paid enough attention to and where might surprises lie?

Objectives
For over 40 years, and through several rounds of IPCC reports, the climate science community has made projections of climate change under specific emissions scenarios. While assessments of the fidelity of Earth System Model simulations over the historical period have been performed for basic variables such as near surface air temperature, internal variability and a relatively small signal in a short observational record has made a comprehensive assessment challenging.

My submitted abstract addresses the internal variability part. I don't know yet whether it was accepted for presentation, but I'm confident that it won't be wasting anyone's time.

At a glance - Evidence for global warming

Paul Pukite at 01:45 AM on 6 December, 2023

But you asked why I commented on this post with respect to ENSO, when it was you that mentioned La Nina in the the post itself. But we're no longer in a La Nina regime but in El Nino.

I just wanted to test the waters here again to see if this site has changed its approach to being more about research than gatekeeping. I keep thinking that the name Skeptical Science describes the charter.

I am skeptical that ENSO is chaotic.
I am skeptical that ENSO is random.
I am skeptical that ENSO is triggered by a change in prevailing winds.

I think I get it — the skepticism is directed not at current models of bleeding edge climate science where millions of $$ are being poured into machine learning for ENSO predictions by the likes of Google and NVIDIA, but at skepticism to combat crackpot models that claim AGW is being generated by subsurface volcanic activity.

Cheers. I think I'm good now.

At a glance - Evidence for global warming

One Planet Only Forever at 14:11 PM on 3 December, 2023

Paul Pukite @23,

I will continue to pursue the points I raised regarding your comment @2.

I am confident that nigelj’s comment about similar trends was regarding ‘a trend like the global average surface temperature data - warming rather than cooling with more significant warming occurring after 1950 than prior to 1950’.

Your comment @2, and later comments except for your latest @23 (sort of), appear to insist that it is not possible to have confidence regarding a warming trend in the NINO 3.4 region (the middle of the equatorial Pacific).

Your comment @2 starts with:

"All these show a similar warming trend." [nigelj’s point]
Not the middle of the equatorial Pacific. (your response)

As my comments should indicate, I learned from and accepted nigelj’s finding of an explanation about the current models indicating a larger amount of warming in the equatorial Pacific (especially the east part) than the actual observations. However, as I commented, that does not alter the incorrectness of your comment @2. But you do appear to have finally accepted your incorrectness (sort of) by ‘seeing’ a warming trend in the NINO 3.4 SST data.

However, I am still confident that it is incorrect to declare that having confidence that ‘the NINO 3.4 SST historical data indicates warming similar to the global average surface temperature data’ requires an accurate explanation for the trend being lower than the current global climate models for that region and it requires that understood influence to be removed from the SST values.

The data is what it is regardless of the mechanisms producing it. Large variations of the temperature data simply requires a longer duration of the data set to have confidence that there is a warming trend. And a lower trend rate will also require a longer data set to establish confidence.

The NOAA presentation of the centered 30-year base periods (linked here) that I provided a link to in my comment @16 helpfully presents the trend of the SST NINO3.4 data set in spite of significant variations in the data values. Each 30-year period contains a substantial variety of the variation. Comparing the 5 year steps for the data starting in 1936 shows that there is indeed a recent trend (more significant after 1950 than before 1950 – consistent with the NINO3.4 chart you included in your comment @23). The 1966 to 1995 values, and all the more recent ones, are clearly warmer than the earlier ones. However, it also shows that the ENSO perturbations in the data are large enough to make the warming trend hard to be confident of, even appearing to potentially be a cooling trend in a shorter data set. The 1981 to 2010 results are not clearly warmer, and may even be cooler, than 1976 to 2005.

Global average surface temperature data evaluations using the SkS Temperature Trend Calculator (linked here) can also provide an example supporting my confidence that the ‘noise’ of ENSO variations do not need to be removed to be able to have confidence regarding a trend.

As I indicated in my comment @17, using the GISTEMPv4 dataset in the SkS Temperature Trend Calculator (linked here) the trend of the data after 1950 is 0.152+-0.018 C / decade (high confidence of a warming trend). I add the following set of shorter recent time periods and the resulting trend and level of confidence (2 sigma value compared to trend value):

Years Trend +- 2 sigma
2016 to 2023 = -0.148 +- 0.513
2015 to 2023 = -0.066 +- 0.428
2014 to 2023 = +0.074 +- 0.379
2013 to 2023 = +0.180 +- 0.331
2012 to 2023 = +0.244 +- 0.289
2011 to 2023 = +0.284 +- 0.249
2010 to 2023 = +0.262 +- 0.220
2005 to 2023 = +0.229 +- 0.129

The longer the time period is the more confidence there is in the evaluated trend. Admittedly the global average surface temperature variation in the evaluations is only about 2 degrees C. So a longer time period would be expected to be required for the NINO SST values because they have larger variation of temperature and a smaller trend. But confidence regarding the trend can still be established without a detailed understanding of the mechanisms at play. And I am confident that the authors of 2012 report you (mis)quoted in your comment @2 had reason to be confident with their evaluation and reporting (repeating part of the quote I had included in my comment @4)

“...While centennial trends are not assessed here, we note that using a reduced period results in more consistent linear trends in SSTs over the 61-year record (Fig. 1), which are significantly positive throughout the tropical Pacific Ocean.”

What the authors of the paper observed and explained, was that the pre-1950 data was not as reliable as the post-1950 data. And since the main interest is ‘warming similar’ to the global average surface temperature which has more significant warming since 1950 than before 1950, the earlier SST values are not that important.

At a glance - Evidence for global warming

One Planet Only Forever at 14:01 PM on 2 December, 2023

nigelj @14,

Paul Pukite’s set of comments here starting with his comment @2 are the matter of concern. Though there is a difference between current developed models and actual observations, that difference is not related to, and does not explain or excuse, Paul’s resistance to learning about the reality of a warming trend throughout the equatorial Pacific.

Note that a warming trend since 1950 appears to also be in the graph of Nino12a that Paul Pukite selected to present @15. Prior to 1950 can justifiably be excluded from the evaluation because of the reasons given by the authors of the 2012 paper Paul misrepresented and still has not indicated he has learned about.

Note that the NOAA information I most recently shared in my latest response to Paul also does not evaluate the SST before 1950 (except for using pre-1950 values to determine the earlier centered 30-year base period values).

Also note that the global average surface temperature had a significant increase of temperature after 1950 compared to the rate of increased prior to 1950. Using the SkS Temperature Trend Calculator and GISTEMPv4:

trend: 1880 to 1950 is 0.038+-0.021 C / decade (little warming)

trend: 1950 to today is 0.152+-0.018 C / decade (lots of warming).

Also note that it is well understood that the land temperatures and polar regions have been warming much more rapidly than the equatorial SST. So the equatorial SST warming since 1950 will be significantly less than the 1 degree C global average since 1950 (much harder to see in a chart with monthly data value swings of up to 8 degrees C like the NINO12 image presented by Paul @15 - statistical evaluation is the proper way : not "I think I see what I think I see").

At a glance - Evidence for global warming

nigelj at 05:44 AM on 2 December, 2023

I don't think PP is a denialist. Have seen his comments at RC. We sometimes just get on edge and jump to the conclusion that anyone who says "flat trend" is a denialist because its a common denialist talking point.

We know the oceans as a whole have warmed considerably since the 1980s. But then you do have a few areas with cooling like the cold blob in the nothern atlantic.

I'm eyeballing Paul Pukete's graphs of the equatorial pacific and at best I can only see a very slight warming trend from around 1970 - 2022. I mean it does look flat or near flat, so I looked for an explanation and this is interesting. I have highlighted the main pargraphs only:. It seems to be consistent with what PP is saying.

Part of the Pacific Ocean Is Not Warming as Expected. Why? BY KEVIN KRAJICK |JUNE 24, 2019

State-of-the-art climate models predict that as a result of human-induced climate change, the surface of the Pacific Ocean should be warming — some parts more, some less, but all warming nonetheless. Indeed, most regions are acting as expected, with one key exception: what scientists call the equatorial cold tongue. This is a strip of relatively cool water stretching along the equator from Peru into the western Pacific, across quarter of the earth’s circumference. It is produced by equatorial trade winds that blow from east to west, piling up warm surface water in the west Pacific, and also pushing surface water away from the equator itself. This makes way for colder waters to well up from the depths, creating the cold tongue.

Climate models of global warming — computerized simulations of what various parts of the earth are expected to do in reaction to rising greenhouse gases — say that the equatorial cold tongue, along with other regions, should have started warming decades ago, and should still be warming now. But the cold tongue has remained stubbornly cold.
Why are the state-of-the-art climate models out of line with what we are seeing?

Well, they’ve been out of line for decades. This is not a new problem. In this paper, we think we’ve finally found out the reason why. Through multiple model generations, climate models have simulated cold tongues that are too cold and which extend too far west. There is also spuriously warm water immediately to the south of the model cold tongues, instead of cool waters that extend all the way to the cold coastal upwelling regions west of Peru and Chile. These over-developed cold tongues in the models lead to equatorial environments that have too high relative humidity and too low wind speeds. These make the sea surface temperature very sensitive to rising greenhouse gases. Hence the model cold tongues warm a lot over the past decades. In the real world, the sensitivity is lower and, in fact, some of heat added by rising greenhouse gases is offset by the upwelling of cool water from below. Thus the real-world cold tongue warms less than the waters over the tropical west Pacific or off the equator to the north and south. This pattern of sea-surface temperature change then causes the trade winds to strengthen, which lifts the cold subsurface water upward, further cooling the cold tongue.

news.climate.columbia.edu/2019/06/24/pacific-ocean-cold-tongue/

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

michael sweet at 07:28 AM on 10 November, 2023

Dean,

I think the explaination of current heat caused by " El Nino, uptick in 11-year solar cycle, Hunga-Tonga and reduction in aerosols due to 2020 phaseout of sulphur dioxide" is not very satisfying.

The El Nino has just started. Usually the effect of El Nino is felt most at the end of the year and the year following. That means we are just now feeeling the El Nino effect. In addition, the current El Nino is described as moderately strong, not extremely strong source. To me that means that only a little of the extrordinary heat of the past 4 months could be attributed to El Nino. Dr. Zeke Hausfather here primarily attributes the current extreme record temperatures to El Nino. I doubt the El Nino has contributed so much heat so early in the cycle. We will see how much hotter next year is. I think El Nino contributes less than 0.1 C.

The solar cycle only contributes about 0.2 C to warming from the top of the cycle to the bottom. While the cycle has increased a lot this year, it is still not peaking out. The solar cycle is not much different from earlier record years. This contribution is also less than 0.1 C.

The volcano is harder to evaluate. Most volcanoes cool the surface but this one shot a bunch of water into the Stratosphere. Since that has not happened before it is hard to estimate. I think the volcano contributes less than 0.1 C.

October was 0.4 C above the previous record year which had a much stronger El Nino, September was 0.5 C above record, August 0.3 C, July 0.43 C higher. These records are usually broken by hundredths of a degree. The past years had stronger El Ninos and the solar cycle was comparable.

Hausfather's estimates of all the forcings do not add up to 0.5C for September. Hansen has been saying for decades that aerosols reduce temperature much more than the models indicate. I fear that Hansen is correct and the unaccounted for warming is coming mostly from the reduction in aerosols. This is due primarily to the change in marine fuels with some coming from polllution controls in China.

If the record heat is caused primarily by the reduction in aerosols it will be permanent. Next year will be hotter because of the El Nino. Future years will build off a new base that is about 0.4 C higher than it was three years ago. Hansen predicted before this year that 1.5 C would be exceeded before 2030. If this year is above 1.5 C becasue of aerosol reduction than by 2030 it is very likely all years will be above 1.5 C and Hansen will be correct. If the volcanoes effects have been underestimated than after next year the temerature should go down for a few years.

Pray that Hansen is incorrect and the volcano caused this years extraordinary temperatures.

Keep strongly in mnd that Drs Mann, Hansen and Hausfather are way more informed about these matters than individuals who post on the internet, including me. I recommend you try to read as many of their postings as possible to determine who you think is being the most consistent.

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

michael sweet at 02:39 AM on 8 November, 2023

I don't think Hansen is worried about thousands of years in the future. He has been saying for decades that aerosols are reflecting a lot of energy back into space, cooling the planet. Reducing fossil fuel use reduces aerosols. The loss of aerosols causes rapid warming. Hansen projects that 1.5C will be exceeded by 2030 and 2.0 C will be exceeded by 2050. He is concerned about changes that will occur while people alive now are still around, about 100 years. He is concerned about multimeter sea level rise by 2100. If Hansen is correct about aerosols the next 30 years will have substantial extra heating.

I respect Zeke and Mann but their explainations for the extreme heat the past 6 months are pretty weak. While the current temperatures are inside the error bars for the models, the temperature this year is extraordianrily hot comnpared to all previous years. I note that the IPCC generally emphasizes what a consensus of scientists think is the minimum amount of change in the climate and temperature. That means that a majority of scientists think it will be worse than the IPCC projections.

The scientists who project damages substantially exceeding the IPCC reports are in the minority. It is very concerning to me that they exist at all. Especially since the last 6 months have been so hot and next year is projected to be even hotter. El Nino does not usually strongly affect temperature until the end of the year.

I agree that "it's important to communicate the incredible challenges we face but without instilling in people's minds the idea it's already a lost cause." But politicians still are not taking action seriously.

What is the IPCC defination of "consensus". It has to be a lot higher than 50%. Is it 80%, 90%? They must have it written down somewhere.

John F. Clauser: the latest climate science-denying physicist

TWFA at 07:49 AM on 28 October, 2023

I get the variability, it's no different from clinical studies, the challenges of getting good data, running controls and placebos, they, too are all over the map and it takes time for a trend to be identified. At least in those we have millions of patients to experiment with, collect data from and alter course of treatment in a short time frame, but we only have one planetary patient, and the treatments proposed are extremely costly and disruptive, and also unfair to many different minorities, an extreme example being Inuits with ATVs and snow machines expected to either erect a solar farm and electrify them or go back to dog teams. Shouldn't they do their part too?

I was in the field of medical imaging and informatics, PACS and EHR systems and such, awarded eight patents and founded several startups. I hired brilliant ADHD software developers who were often wrong but never in doubt, when they would have a major system upgrade they wished to perform they would ask if they could do it during their work day. Why? Not because their favorite show was on that night, that show was in front of them 18 hours a day. No, it's because that's when our customers were also busiest, and that way if there was a problem they would discover it much more quickly as every button on my phone lit up with screaming radiologists.

I would explain to them that our clients are customers, not lab rats, you exist to serve them, they do not exist for you to write perfect code, you will do it at midnight and be prepared roll-back at 5. In the climate debate the client is the people, not the planet, as George Carlin put so well decades ago, the planet will be fine long after we are gone, so as in medicine the first rule is to do no harm.

What I see going on here is similar, folks who want to move ahead full blast, others like me who wish to see more data and test the models, others who could care less either way, either because they feel they have no say in it anyway or have the wealth to both buy a pair of Teslas AND a second home up north.

Taking the current models and applying them to some other data set than the one they were developed upon is the right way to test them. Perhaps it is classified, but thermocline levels and or temperatures obtained by submarine or sonobouy, some type of terrestrial sub-surface measurements, well water temperatures, whatever, anything that gets us as far away from the noise of weather and cloud reflectivity, there has to be something else out there we have been measuring for the past and will be for the next fifty years that can show the same trend, no matter how small, no matter the lag. There must be some other canary out there.

Temperatures above and below the weather would put to rest silly arguments about hurricanes in the East Pacific, which if never making landfall two centuries ago may never have been recorded, let alone measured, and other sensationalism thanks to mass media and competing information leading to mass hysteria.

Kind of reminds me of the windshield pit fiasco in the Pacific NW back in the fifties when some thought fallout from bomb tests in the Marshall Islands was doing something to their cars, the consensus among the social psychiatrists being that for the first time folks were looking AT their windshields instead of THROUGH them.

John F. Clauser: the latest climate science-denying physicist

Rob Honeycutt at 06:32 AM on 28 October, 2023

TWFA... "It's not that I don't care about surface temperature, I care about whether the models for surface temperature have been applied to predicting temperatures above and below, a perfectly logical query."

Yes, this is a perfectly reasonable and logical query. So, pause right there before you move forward with any assumptions.

The answer to the best of my understanding:

Yes, climate models are applied to the surface and up through the various layers of the atmosphere. Once you get above the surface you run into challenges with measuring those various layers. The surface has the advantage of extensive direct data, above that you have to rely on either balloon data (which is sparse) or satellite data (which is an indirect measure of temperature and actually poorly measures some layers, like the mid-troposphere).

For deep ocean models, I'm unsure. But I would imagine those would have little affect on shorter time scales and is more important measure as a longer term reservoir for accumulating heat energy.

For sea surface or near surface modeling, there is a lot of coupling between the ocean and atmosphere, thus those are going to be inherent to climate models.

The other important point to understand about climate modeling is that they are, as mentioned earlier, "boundary conditions" modeling.

You can think of "initial conditions" modeling like the hurricane storm tracks you see on the news. We know where the model is and the models project the likelihood of where it will track over the following days.

Climate models are different. What they're doing is running model ensembles. Essentially, they're doing longer term weather/climate runs, over and over, in order to see what the mean state is. As they say, "All models are wrong, but they are skillful." We're not asking models to tell us whether this year will be warmer or cooler than the last. We know that's inherently noisy. We're asking climate models to tell us, over time, how much warming we can expect to see.

Understand that? They're wrong because one model run will say next year is warmer and another will say it's cooler. But they are "skillful" because they can tell us, with a high degree of confidence, the longer term trend for the climate system.

John F. Clauser: the latest climate science-denying physicist

TWFA at 06:09 AM on 28 October, 2023

It's not that I don't care about surface temperature, I care about whether the models for surface temperature have been applied to predicting temperatures above and below, a perfectly logical query.

If we have a model that can replicate historical data there is a good chance it can predict as well, but if the models have only been devloped using surface data, adjusted to match history, then you should be able to take the exact same model and run it to replicate historical and predicted data for temperatures aloft or level of thermocline below.

Sure the values and rate of response will be different, but the trends should not, and that is what I am looking to see. As you know, any temperature observtions at flight levels would be at pressure altitude and need to be corrected to true altitude. There are decades of oceanic route position reports, I seem to recall it was typically four or five on the North Atlantic tracks, probably there are double that on the Pacific, don't know if that data is in a silo somewhere or integrated into other, but it is historical and of interest to me.

At one site on "the other side" they showed data that indicated temperatures aloft at 200 hPA have NOT been increasing above 1.7 per century but the models predicted 4-4.5, so of course ALL the models are crap.

When I explained to them I would not expect them to if the readings were at pressure altitudes because I know from experience that unless there is a significant diversion from the standard lapse rate, weather, they will not... even if all the forests on earth were afire, at a 200 hPA pressure altitude of about 40,000' I would expect virtually no variation, and at 5,000' without including the world inferno lots of noise in the signal and would want to look deeper at such a data set to make sure it was as closer to standard atmosphere conditions as possible and corrected to AGL.

As you can imagine, I got the same kind of crap there, what does it matter, I don't have a clue, all the studies studying all the models of the other studies show them all to be wrong, etc., etc. Nobody is right all the time, but nobody is wrong all the time either, even if they turn out to be right for the wrong reasons.

So, my search will go on, if there is anybody else here who understands what I am looking for and has something to offer other than, "Get a PhD in climate studies, otherwise believe what we say" I would love to hear from you.

John F. Clauser: the latest climate science-denying physicist

Rob Honeycutt at 03:57 AM on 28 October, 2023

TWFA... What I'm trying to convey to you is, climate science is a complex topic and you need to spend far more time than you currently have to get a good grasp of what is happening. Instead, you're starting from assumptions and are merely grasping for arguments to support that position, without endeavoring to skeptically research the topics.

"I am looking for information, not confirmation..."

This is clearly not the case, though, being that everything you've stated or "asked" has been fundamentally based in rejection of the established science.

Look, TWFA, there is a lot to understand about this topic. I am not an expert. But what I have done is taken the time to read a large body of the available research. There are many here on this site who are willing and capable of offering answers, but you're going to have to approach the subject with a little bit more humility and awareness of your current state of understanding.

If you have real questions, ask them. But don't be offended if people here give you answers you don't want to hear.

For instance, when you say, "I am just looking for a few that have run the models against some mid tropospheric level data set, or deep ocean temperatures, or anything other than surface temperatures." This is exactly what I'm talking about.

Why would you dismiss surface temperature? What about mid-troposphere temps do you think is more interesting? There are plenty of articles on this site discussing those topics already. All of those articles reference the available peer reviewed science.

Every time I hear someone call themselves an "independent thinker" it raises a huge red flag for me. Why would you believe every climate scientist out there is not an independent thinker? Why would you assume the broad consensus on climate change isn't a product of independent thinking across a broad spectrum of experts in their relative fields?

In order to truly be an independent thinker you first need to inform yourself about the subject you're thinking about. Without doing that, you're merely a rejectionist. If you're offended at being told this, perhaps you're just looking for an easy exit.

John F. Clauser: the latest climate science-denying physicist

TWFA at 01:28 AM on 28 October, 2023

Rob, with the PIREPs it was not bizarre at all, I was meaning for historical oceanic data that predates the modern technology, in my day position reports on HF always included wind and temperature. Attack, attack, attack... it's amazing.

Anyway, you keep repeating the same thing, "You obviously are a numb-nuts who hasn't read anything, there are tons of studies and everybody is in agreement, get lost".

I know how to read, have been reading clinical and technical papers all my life, I don't want to screen abstracts or read tons of studies, I am just looking for a few that have run the models against some mid tropospheric level data set, or deep ocean temperatures, or anything other than surface temperatures. You claim to be the expert, presumably you have read all the studies so you should be able to know right where to look, perhaps cite from memory. I am not the expert, but that does not make me a potted plant.

I am not here to argue, nor am I here to cheer or circle-jerk, I came here hoping to learn, there are plenty of advocacy sites on both sides, lots of noise, I was hoping this was not one of them.

There are two areas where I need more information, one is the whole cloud reflectivity and convective energy transfer process, and the other is whether the models we are relying upon work with data sets other than surface temperature, you can't have surface temperatures going up but everything else remaining the same and claim "the planet" is getting warmer.

I have children and grandchildren who look to me for advice because they know I am an independent thinker who has done pretty damn well so far thinking independently, I am looking for information, not confirmation, if this site is just another cheering section I will be happy to move on, nothing new to learn here.

John F. Clauser: the latest climate science-denying physicist

Rob Honeycutt at 00:26 AM on 28 October, 2023

TWFA: "... if the atmosphere and planet is heating up, so should the temperatures at 20,000' or 40,000', or even deep ocean temperatures, there should be plenty of data available at least for the former, weather balloons and PIREPs, it should track the models just as well and if not we would need to know why."

Each of these comments from you is a fascinating demonstration of how little you've actually looked at the science of climate change. There is published research on all these topics and there is a very broad, deep agreement across research fields that human emissions of CO2 are the primary cause of warming of the past 50 years.

And the PIREP bit is espectially bizarre. Being a pilot myself I know what you're talking about, but you should also know that PIREP's tend to be few and far between. They're helpful but not reliable. In addition, those PROG charts you pull in to ForeFlight or download via ADS-B in, those are produced through the same models used for climate models. They're merely initial conditions modeling (weather) as opposed to boundary conditions modeling (climate).

All this and still you have yet to say one word about Clauser's claims.

John F. Clauser: the latest climate science-denying physicist

Rob Honeycutt at 00:14 AM on 28 October, 2023

TWFA: "...one of the problems I have with all the models I have seen is that they appear to have been adjusted or tweaked to global surface temperature observations..."

This is a nice demonstration showing that you haven't spent any time at all seriously looking at climate models. You've merely made an assumption and make statements that support what you prefer to believe without ever taking a serious look at the data or reading the underlying science.

Do you understand that Syukuro Manabe recently won a Nobel Prize precisely because his models from the late 1960's have been so accurate.

John F. Clauser: the latest climate science-denying physicist

TWFA at 15:37 PM on 27 October, 2023

Yes, Michael, and I can confidently predict that an even more powerful hurricane will someday top that one even if we are carbon neutral or dead, on the other hand I can state with equal confidence that at some time in the past a more powerful one hit Acapulco as well, there is no way one can prove that the one yesterday was "of greater force than any previously occuring in the East Pacific Ocean".

Do you even realize how rediculous such a claim appears to be? Chance and time alone disqualify such a statement just as vastness and time assure there is life elsewhere in the universe, but neither can be proved without evidence. A CQ or TV signal of Hitler opening the '36 Olympics coming from Vega would be evidence, but proving something never happened, or something that but for reality would have otherwise happened, is extremely difficult, sort of like proving Schrödinger's cat to be alive or dead without opening the box. Until such time as we can open that box a larger hurricane in Acapulco in either the past or future will both exist and not exist.

But moving on, one of the problems I have with all the models I have seen is that they appear to have been adjusted or tweaked to global surface temperature observations, which is not necessarily a flaw in their creation but possibly a failure in their useful application, and it seems to me that there must be some other data set those models could be run against, with and without the anthroprogenic forcing, basically turning it on and off and looking for the same results on a different sample set, which would clearly show the model works elsewhere, and possibly everywhere.

Is it the lamp or the light bulb? Screw in another bulb from another lamp and see what happens, if it comes on it was the bulb, if still off it might be the lamp or both bulbs... unless the one you screwed in was hot, in which case it is the lamp. Pretty simple truth table, if the atmosphere and planet is heating up, so should the temperatures at 20,000' or 40,000', or even deep ocean temperatures, there should be plenty of data available at least for the former, weather balloons and PIREPs, it should track the models just as well and if not we would need to know why.

John F. Clauser: the latest climate science-denying physicist

TWFA at 02:47 AM on 27 October, 2023

I seem to recall that Bill Gates and Steve Jobs did not have any peer reviewed papers on computer science when as teenagers they charted the future of computing and communications and folks invested millions into their unproved, non peer reviewed theories.

I think it is healthy to get outside observation and critique from folks with good minds that may not be "set". One does not have to be a specialist or have studied the field all his life to ask why if none of the current models can accurately reproduce what has happened over the last century why should we have faith in their predictions for the next?

And "faith" is what it is all about, because nobody can "prove" the future while in the present, but we can hopefully understand the present with results from the past... if we choose to pay attention to them, and that applies to far more than climate science.

When folks accuse others of being "deniers" it means they themselves must be "believers", neither can prove their case with facts, neither can prove something will or will not happen in the future until the future arrives, meaning until then we are talking about religion and not science. "Show me a video of God and I will believe" vs "How could all of this come to be without Him?" If 99% of alleged scientists agree on something either it is no longer science or they are not scientists, it is either religion or they are evangelists.

As a non-peer reviewed entrepreneur, renaissance man and pilot flying ABOVE clouds I have always marveled at the weather, the incredible energy conversion and transmission capacity of phase change and latent heat, for decades before Clauser came along I have been screaming about cloud reflectivity because I have seen it first hand... all that light beneath me is going back to space. 70% of the Earth's surface is water, from which clouds will form, temperature goes up, more clouds form, more reflection, less insolation.

It's not rocket science, or even computer science, put a pot of water on the stove, no matter how high the heat the water temperature never gets above boiling. If what Al Gore said at Davos this year were true, that the oceans are boiling, presumably not just where magma is erupting, it would have defied the laws of physics and thermodynamics, it would be impossible to capture and retain such heat with the 100% cloud cover we certainly would have.

At a glance - How do human CO2 emissions compare to natural CO2 emissions?

Bob Loblaw at 00:51 AM on 3 October, 2023

amhartley @ 4:

You've had a few answers that might help. I'll add the following.

You mention "thickness of the atmosphere". When discussing radiation transfer (absorption in this case), it is not the physical distance that matters. It is the number of molecules of the absorbing gas that affects the probability of radiation absorption. You can pack the same number of molecules into a short physical distance, or spread them over a larger distance, and the absorption characteristics will remain the same. In radiation transfer, you will see the term "optical thickness" or "optical depth". to distinguish this from physical distance.

This post on Beer's Law gives an illustration of this.

...but yes, IR radiation emitted at low altitudes will be unlikely to reach space directly. But at each level, the atmosphere also emits IR radiation, and the further up you go, the more likely it is to reach space directly. Understanding the greenhouse effect writ large requires looking at both absorption and emission, and at all levels.

There is more discussion of this on the Beer's Law post I linked to above, but a useful resource online is MODTRAN. You can play around there with a full atmospheric IR radiation transfer model that includes all these effects.

2nd law of thermodynamics contradicts greenhouse theory

Bob Loblaw at 04:08 AM on 28 September, 2023

Frankly. likeitwarm, you are simply not understanding what you are reading....

In comment 1590, you quote a paper that says "Thermal energy..." and "mechanical contact"

IR radiation is not "thermal energy". It is "radiative energy". It does not need mechanical contact - that's why radiation from the sun reaches us through the vacuum of space.

The quote you provide, and the paper you link to, are very, very confused. Radiation does not have "temperature". Radiation has no memory of what temperature it was emitted from - it just has a wavelength and frequency.

In its figure 2, the paper provides Planck curves for perfect emitters. Gases are not perfect emitters.

The paper starts section 7 (titled "RADIANT ENERGY IS NOT ADDITIVE") with the following:

Where most people have trouble intuitively visualizing electromagnetic energy and understanding E=hν is in recognizing that electromagnetic energy cannot be summed over frequency or wavelength, as is done today by virtually all climate models. It makes no physical sense to sum frequencies. For example, red light at 400 THz plus violet light at 700 THz does not equal ultraviolet-B radiation at 1100 THz

This demonstrates that the author is pretty much clueless as to what climate models and radiation models do. Nobody sums frequencies in the manner he suggests - they can and do (properly) sum the energy at different frequencies. That's called an "energy balance".

In section 11, the author cites Angstrom's 1900 paper. We've actually learned stuff since 1900, and Angstrom's errors are discussed on the advanced CO2 is saturated thread.

You need to find some less obvious sources of misinformation, likeitwarm.

2023 SkS Weekly Climate Change & Global Warming News Roundup #36

sailrick at 16:51 PM on 10 September, 2023

Extreme heat is forcing America’s farmers to go nocturnal

"Rising temperatures in key agricultural regions across the United States are leading more farmers to harvest in the middle of the night to safeguard the quality of their crops.
Heat has become a major economic threat to the agriculture industry, and it’s only expected to get worse. By the end of the century, climate change could lead to worldwide crop damage five to 10 times greater than conventional climate models have predicted, according to a 2021 study published in the Journal of the European Economic Association."

https://www.washingtonpost.com/business/2023/09/09/heat-night-harvesting-farmers/?utm_campaign=wp_post_most&utm_medium=email&utm_source=newsletter&wpisrc=nl_most

Climate Confusion

Bob Loblaw at 05:24 AM on 4 September, 2023

Markp:

I am also not going t try to wade through a long post, either. I will respond to one small portion. You state, with respect to models:

And as my primary experience (nearly 30 years now) has been in the financial arena for many "quant" strategies where, in that industry it is painfully common to see wonderful quant investment funds with great backtested results finally have some real money thrown at them and start a live track record, only to see the live returns look nothing like the lovely return characteristics of those backtests, I confess a lot of my skepticism comes from just that type of environment.

All I will say is that climate models likely bear very little resemblance to the sort of models you run into in financial topics. For one, climate models have an awful lot of physics in them. They are not pure statistical models (although statistical models do get used in climatology). The laws of physics put some pretty strong constraints on how climate models behave.

Climate Confusion

Markp at 22:43 PM on 3 September, 2023

For Rob: I know I have not provided much data to back what I've been saying, but that's mainly because I was going on the assumption that you may already be aware of the data that could support me. In other words, I don't think what I've said is uncontroversial from a data point of view, but I do accept that it might be controversial from the point of view of making those holding a mainstream view (and I know that's vague) uncomfortable.

I disagree with little of what you say about climate in this last post. From your list of 8 items, only 1,4 and 5 are problematic in my view. Unfortunately, those few items are weighty:

"A lot is happening towards decarbonization" is vague enough to require examples to qualify the statement. There has definitely been a lot of talk about decarbonization, but as 2022 saw global emissions hit a new high of 36.8 Gt, according to the IEA's report "CO2 Emissions in 2022" one has to ask what decarbonization achievements, what action, in place of mere talk, can we point to. Renewable energy production plus use of EVs, heat pumps and who knows what else saved about 550 Mt. Fine. But this growth rate (growth of renewable contribution) won't hold up. So when you say "a lot" is happening, what's that really mean? And could you give just a few bullets on how you think we'll achieve net zero by 2050?

I'm also curious to know how much your vision of "net" zero relies on offsetting schemes, because I don't trust them and fear that they are being relied on too much for comfort.

As for what happens to the rising temperatures in a net zero 2050, we'll have to wait and see.

I'm certainly with you on breaching 2C by 2050, but since I've got little hope we'll be anything close to net zero by then (for whatever net zero is actually worth as long as we've got all the offestting nonsense thrown in there) it looks worse to me than to you.

Finally, and to change the subject a bit, I think the talk about models went too far. I'm not saying models are bad, just that they're being relied on too heavily in certain important cases. And as my primary experience (nearly 30 years now) has been in the financial arena for many "quant" strategies where, in that industry it is painfully common to see wonderful quant investment funds with great backtested results finally have some real money thrown at them and start a live track record, only to see the live returns look nothing like the lovely return characteristics of those backtests, I confess a lot of my skepticism comes from just that type of environment. Still, when we continually see news reports with headlines running "Researchers present shocking new data that climate change is happening much faster than expected" and the previous expectation was based on models, I don't feel at all surprised. I've just had a look at the "myths" section of Skeptical Science specifically at the models myth and I also see there that most of the argument seems to be toward trying to convince climate deniers who say models are all wrong that GW is real. That's clearly not me.

For Eclectic: I don't think I've written too much, do you? I know people these days don't like to read anything longer than a twitter post, but I don't think your assessment here is fair. I've tried to keep it short, in fact. Like I said, I assumed, and maybe wrongly(?), that you folks had a decent understanding of the data already, and could follow commentary like mine that took a broader look at things rather than fussing over citations and decimal points because I'm not claiming anything that boils down to a disagreement over small measurements but has been more about one's basic orientation: some of you seem to be wearing rose-colored glasses in my view, like too many people are.

As for the mirror concept, if the goal were to limit global temperature rise to 2C by 2100 we would need about twice the surface area of the contiguous USA. Although these reflectors would be useful in many instances, like on rooftops, parks, outdoor markets, reservoirs, etc., the main idea is for them to be used in agricultural settings because there's a lot of agricultural land, and because the reflectors would bring both local benefits to the crops by cooling, saving water and increasing yield, and contribute to global cooling. How to do that on a large scale is a problem that needs to be worked out. Any cropland managed by tractors and other large machines would either need to involve reflectors that would be removed from time to time for those machines to do their work, which wouldn't be easy, or they'd need to be placed so as not to interfere with those machines, perhaps by having them suspended vertically alongside crops rather than horizontally over them. And of cource, horizontal coverage would not involve blocking all available sunlight as to choke off photosynthesis, but as most crops can thrive with up to 30% shading, it would be placed intermittently. Anyway, this is the rough idea. Reflectors made from PET and aluminum cans from landfill provide more than enough for this level of scale, but other reflector constructions/materials could pop up as well. If you feel this isn't the type of detail you'd like to see, I'm not allowed to offer more. Not to protect technology or profits, because this comes from a nonprofit, but simply because I'm not authorized. As some of you know, the science takes time. We're working on it.

If that surface area seems "too big" as in "nobody will go for that" I can certainly feel that, but what choice have we got? The Earth is big. We can do it. We've got 4 million miles of roads in the USA. When cars first got started, nobody would have thought that possible. All of our climate "solutions" are by nature on a grand scale. Nothing to do about that as far as I know. And why people might balk at lots of mirrors/reflectors when they seem to think DAC (or your solution of choice) can clean (enough of) the entire atmosphere, I'm stumped.

Climate Confusion

Markp at 05:22 AM on 3 September, 2023

Hello

No, I'm not at all advocating that individuals adjusting their lifestyles are the answer, far from it (I'm surprised to hear this from you!), but it is something that must be done. Average people pushing the politicians and business leaders to act is necessary as well, because as we can see, without that they'll continue making targets and holding discussions that don't get us anywhere.

This is going to come down to us agreeing to disagree, I guess, for example regarding the IPCC and all the supposed "progress" we've made. I know that most people in climate science (scientists and others) think like you, that a lot has been done, etc. I just don't buy it. We've certainly managed to elevate the overall knowledge of GW among everyone - people from all walks of life (not with the honesty and clarity that is needed in my opinion, but...). But that has not translated into the kind of action we need by a LONG shot. It's politics and it's scientific reticence (i.e. David Spratt) and many other reasons, but it's there, staring us all in the face. Maybe I'm just speaking here to the optimists, 45-years of experience or not. I don't know. But if you think you shouldn't take me seriously because of my attitude towards models re "the end of temp rise" I'll just reiterate that it's not just me but people like James Hansen who have expressed those opinions. Just look at his latest tidbit: "Equilibrium Warming = Committed Warming?" where he writes in the 4th paragraph: "...climate science should be focused on data. That's the way science is supposed to work. However [the] IPCC is focused on models. Not just global climate models, but models that feed the models, eg. Integrated Assessment Models that provide scenarios for future GHG levels...sometimes the models contain hocus-pocus. As we mention in our current paper, they can assume, in effect, that 'a miracle will occur.'" And as you know, he's not the only one to criticise the overreliance on models. I'm assuming you are all familiar with Spratt and Dunlop's "What Lies Beneath."?

At the end of the day, scientists are no different from anyone else in this world where we all have to struggle for survival and protect our jobs and reputations and do things we have to do but may not believe in. Research isn't done for fun or for pure curiosity unless one bankrolls one's own laboratory, which few do. It's done to support the money, make a product, build a name for oneself, etc.

So people like (unnamed) set up for-profit companies as sidelines in addition to their responsibilities with their universities and, look what he just did: sold Carbon Engineering for over $1B. Nice. Ka-ching. You can't sell simple solutions for that kind of money, can you? And Climeworks, when are they going to have an IPO and cash-out, for worthless DAC? And this is all because the IPCC said "We MUST do this!"

An extremely important statement from the foreward of "What Lies Beneath" is from Hans Joachim Schellnhuber, professor of theoretical physics, etc., long list of credentials, when he said we are running out of time and so "...it is all the more important to listen to non-mainstream voices who do understand the issues and are less hesitant to cry wolf [than for example those scientists working with the IPCC]".

I work with those non-mainstream scientists because they are the ones who seem to be cutting through the BS towards real solutions that give us more than hopium.

Let me just ask you, and I am trying to be fair to the scientists in climate, generally speaking, because I imagine the vast majority are really doing their best. They aren't free to do what they might if they weren't trapped in the system we all are trapped in. (I know one who is a physicist but works with the IPCC on policy and he told me once "You have to trust your institutions, Mark"!!! Really. I trust the post office to deliver a letter. I don't trust politicians to solve global disasters that require those in power taking home less money.) But let me ask: if scientists really have been trying as hard as they could for decades now to come up with ways to stop rising heat and protect life on Earth as fast as possible, why has nobody else but a man who left his academic career at Harvard behind in order to found a nonprofit been able to come up with the solution staring us each in the face every morning when we brush our teeth, involving mirrors? Could it maybe have anything to do with the fact that it is just not very sexy? Honestly, I cannot understand or explain it any other way. And I've seen big-wig scientists in the climate sphere hear of this and say "where's your peer-reviewed research?" instead of just turning their brains on and thinking about the idea first. "Hey, makes sense, pretty obvious, actually...could be some complications, but overall, interesting idea..." (Kudos to Eclectic on this one) No, instead they just wanted research to back up the idea that ice will melt in a hot frying pan.

Well...would have been more fun over a beer. Take care.

A Frank Discussion About the Propagation of Measurement Uncertainty

Bob Loblaw at 05:45 AM on 2 September, 2023

Hi, ICU/Everett.

I am aware of the PubPeer discussion of this recent Pat Frank paper. I have started participating on that discussion as Camponotus mus - a pseudonym assigned by PubPeer. I saw that link to NoTricksZone, and have a short response waiting in moderation at PubPeer. (As a new, anonymous user at PubPeer, I understand that my comments will always go through moderation, at least for a while.)

I have only looked quickly through that NoTricksZone post, and it seems that Pat Frank is mostly just asserting he is right and the whole world is wrong. Part of my PubPeer response is:

I see that you are arguing that averaging is not the same as weighting. That is quite an amazing claim, as the average of two numbers is algebraically equivalent to weighting each number by 1/2. You do understand that (A+B)/2 is identical to A/2 + B/2, and that this can be re-written as (1/2)*A + (1/2)*B? If you think this is not correct, then I would add basic algebra to the topics that you do not understand.

He also seems to claim that uncertainty can't use the rules of statistics, such as the covariance term I mention in the OP. This is certainly a most bizarre idea, as the GUM makes extensive use of statistical models in demonstrating concepts of uncertainty.

Overall, Pat Frank's response at NoTricksZone looks like he is in hagfish mode, as described in DiagramMonkey's blog post. I do not think it would be productive to try to refute it here unless Pat Frank comes here and makes his arguments here. A read-this-blog/read-that-blog cycle will not be at all productive.

Of course, if Pat Frank does come here, he would be expected to follow the Comments Policy, just like anyone else.

Climate Confusion

Markp at 03:04 AM on 2 September, 2023

I am not a scientist, but I've been working in climate science for a couple of years now.

I wouldn't say I dismiss models, I'm just careful with them. Perhaps "garbage in, garbage out" is more common an expression to describe models in the financial world than in the natural sciences, but even so, when it comes to climate modelers I'm merely echoing sentiments from those like James Hansen, who clearly value models but prefer using real data, real-world, whenever possible. I've spoken to established research scientists who laugh off the climate modelers who so cheerfully say "temperatures will just stop rising" if net zero is achieved. These are people I trust. They've had long careers doing real science, not short ones playing with computers.

And Rob, believe me, I do live a low-carbon life myself but I know very few others know or care about the need for that. The problem is, the accepted wisdom for many years now has been to not alarm people with GW talk, and churn out messages with hope and optimism, so what has happened is that people pretty much think "the experts" are taking care of things and there's nothing to really worry about. The person on the street has no clue how bad things are or how soon things will get very bad. No wonder they don't change their lifestyles further than maybe switching to a new sexy Tesla and eating vegan once a week.

I'm also involved in the renewable energy business and that's definitely been an excellent development but again, people are being misled into thinking that's all we need to do, but it's not going to happen. Have a look at Simon Michaux's work.

We've had the IPCC for 35 years and not much to show for it, and anyone who doesn't believe that is either simply ignorant or is fooling themselves. The IPCC plays politics with science. We need to take their estimates and double or triple them to achieve results close to reality.

All I can say regarding decarbonizing is that the money and the power is dead set against it because they're only concerned about today's profits, but as more and more of the world burns up, as food insecurity gets worse and water scarcity as well, their hands will be forced. The question is: will there be enough time then? Will the "laser focus" that might (might) be squeezed out of people when their backs are against the wall be too late? What is required, at the very least since people aren't acting like adults, are laws limiting waste in all industries, in all areas of government, and in our private lives, but is that coming? Are laws restricting unnecessary consumption coming? Laws banning the worst of the world's luxury goods would put a big dent in the fattest carbon emitters and send a message to all those people idolizing such frivolous living but is that coming? We could put tight curbs on new car sales and enforce drastic changes to allowable car specifications (reduction of size/weight/horsepower). We need governments to enforce "work at home" for all industries and jobs where that's feasible. We need public service messages telling people to stop trying to "live large," we need celebrities to publically downsize their lifestyles, television shows to stop glamorizing the selfish life... the list is very long. So much needs to be done and could be done, but is it? Scientists gluing themselves to bridges is what we need, it's just about the only sensible thing to do this late in the game to make people wake up, but instead of getting the message people scorn them and governments lock them up. We cannot blame these protesting scientists. They've been asked to do something they were never trained to do, and for which no infrastructure exists, and to make matters worse, they're being pushed into solving this emergency by adopting a profit-making model that flies in the face of the spirit of science.

The way I see it, we've got about one decade of "somewhat normal" life left before the food insecurity hits the privileged classes hard, and at that point, the societal collapse that has already begin is going to be much more life-threatening than heat. Net zero goals for 2050 may no longer matter when everything begins to fall apart.

As for the mirror concept, all the details are being researched but we're not talking about traditional glass mirrors but rather "specular reflectors" such as what you get combining PET with aluminum for a cheap, thin, durable, flexible mirror-like tool. These are already in use for local heat adaptation, but going from adaptation to global heat mitigation is just a matter of scaling up, and there are plenty of resources for it, unlike so much of the other ideas floating around. Plastics with no metal at all are also being developed that could be used. The whole concept is a simple evolution of white paint, which is not feasible for many reasons including the fact that it gets moldy and needs regular attention and re-surfacing.

Climate Confusion

Eclectic at 23:21 PM on 1 September, 2023

Markp @23 , to respond is simple. Name the person you are addressing, and preferably add in the # post number, for greater precision. Occasionally that # goes "wrong" if the Moderator has altered some post numbers ~ but usually posts go onto the thread in the chronological order they were received.

Again, I am not sure why you are bothered by "models and scenarios". As you say, the social/political/technological response to CO2-derived global warming is rather tardier than ideal, in slowing and eventually halting the current rapid warming. Yes, decades.

Simply apply common sense, and remember the first step needed is the reducing of human-caused CO2 emissions. Eventually, the CO2 level stops rising (and if you are curious, you can observe how much more warming occurs after that . . . so no actual need for "models"). Then you can observe the speed of subsequent CO2 level fall . . . and take further high-tech action if that seems warranted, in order to accelerate the CO2 decline. If not going the high-tech route immediately to begin with!

Probably best to ensure the CO2 does not drop below about 350ppm (since eventually the natural Milankovitch-cycle cooling will start to show). That "natural cooling" has been estimated to become problematic in roughly 15,000 years . . . so not an urgent problem! Plus humans will then have the option of warming the planet by burning small amounts of coal (assuming we have been wise enough to keep a goodly amount of coal available for such future need . . . although by that stage presumably we will have the option of heating limestone per fusion-powered electricity).

Markp, your idea of mirrors (ground-based, not space-based) seems reasonable in theory . . . but what about the practicalities? Please go ahead and "show your workings" for areas needed / desirable locations / dollar cost per sq. meter / CO2-cost of building & installing mirrors / and so on.

Remember the old axiom : Politics is the art of the possible.

Stop worrying yourself about models ~ leave the models to the scientists. Your personal responsibility (to yourself and others) means taking practical action with what you can do now .

Climate Confusion

Bob Loblaw at 22:31 PM on 1 September, 2023

Markp @ 23:

Ah, I see. You simply dismiss models. It must be really difficult for you to do any science with no models of any sort. Since science is based pretty much entirely on models (descriptive, statistical, mathematical, etc.), dismissing models is pretty much saying you dismiss science writ large.

...but then, the people doing the science (with models) and presenting results, you dismiss as making "assertions".

I'm glad you "asserted" this viewpoint.

Climate Confusion

Markp at 21:50 PM on 1 September, 2023

Not sure how to respond to comments to my comment... There is no "reply" etc., featured in those comments, so I'll just say to Eclectic that I'm sorry you find my last paragraph unclear, and to Bob Loblaw and Rob Honeycutt: I'm clear on the difference between different types of "zero" CO2 scenarios, whether they imply constant concentrations or not. And Zeke's "explainer" is nice but is only a case in point: too many people simply assert that under a complete end to human emissions scenario, whereby natural uptake through oceans and trees continue drawing down CO2, heating will stop. Almost immediately. And they seem to base that belief purely on what has been modelled. And as everyone should know about models: garbage in, garbage out. The models don't reflect reality, though they try. Their inputs aren't complete, but merely partial. For example, ZECMIP is only CO2. The fact is, when we talk about hypothetically achieving no more human emissions, we're talking about a time in the future that is not tomorrow or next year or next decade, but at the very least, several decades, at least going by the extremely lazy response by humanity thus far. Correct? So by that time in the distant future, as emissions have continued, and tipping points have tipped, many things will have likely changed that our current thinking (or modeling) does not account for. So it is a bit silly to claim that temperatures will just stop IF/WHEN/? we ever manage to end human emissions, or "net" end them through the net zero concept. We place far too much reliance on models here, or rather I should say, those who are cheerleaders for net zero do.

So to Eclectic, I'm not proposing an alternative to reducing emissions. We need to reduce emissions. But that won't be enough. We also need to try the best form of SRM we can manage, which in my view is land-based mirrors, because the tech is here now, it's low tech, non-toxic, completely scalable, does not block sunlight from reaching our flora and fauna, and has an immediate effect on warming, unlike all the downstream GHG management methods.

A Frank Discussion About the Propagation of Measurement Uncertainty

bdgwx at 03:46 AM on 26 August, 2023

I'm sure this has already been discussed. But regarding Frank 2019 concerning CMIP model uncertainty the most egregious mistake Frank makes is interpretting the 4 W/m2 calibration error of the longwave cloud flux from Lauer & Hamilton 2013 as 4 W/m2.year. He sneakily changed the units from W/m2 to W/m2.year.

And on top of that he arbitrarily picked a year as a model timestep for the propagation of uncertainty even though many climate models operate on hourly timesteps. It's easy to see the absurdity of his method when you consider how quickly his uncertainty blows up if he had arbitrarily picked an hour as the timestep.

Using equstions 5.2 and 6 and assuming F0 = 34 W/m2 and 100 year prediction period we get ±16 K for yearly model timesteps and ±1526 K for hourly model timesteps. Not only is it absurd, but it's not even physically possible.

Climate Confusion

Markp at 20:25 PM on 23 August, 2023

I'm still not sold on the idea that zero or net-zero emissions implies no future warming, as Evan says "A world where the best we do is to stabilize CO2 has, for all intents and purposes, "warming in the pipeline", something that does not occur if and when we reach net-zero emissions."

First of all, it is not ultimately GHGs that determine warming, it is the EEI that does that. In other words, as I understand it, if the EEI is positive, but GHG emissions are zero, Earth still warms.

I also find it problematic that the idea of "zero emissions" or "net-zero" seems to imply to most people that all we are talking about are human emissions, when the possibility of an end to human emissions could exist while (significant) non-human emissions (for example permafrost melt) could still create warming, so that we are actually not at zero or even net-zero emissions regardless of source.

I have long searched for a really solid scientific explanation of the concept of baked-in or committed warming that carefully tries to help people understand why some scientists say it exists and some say it doesn't. But the Zeke piece (and I don't trust for-profit scientists on this) is not convincing and neither is the Scientific American piece.

Neither is the MacDougall 2022 ZECMIP study paper which clearly states "The most policy relevant question related to this research is: will global temperatures continue to increase following complete cessation of greenhouse gas and aerosol emissions? The present iteration of the study aims to answer part of this question by examining the temperature response in idealized CO2-only climate model experiments. To answer the question in full, the behaviour of non-CO2 greenhouse gases, aerosols, and land-use-change must be accounted for in a consistent way," which is another way of admitting that ZECMIP at this point is still "garbage in, garbage out."

In fact, the pieces I have found seem to rely purely on models which are always incomplete, as is ZECMIP.

And neither is this piece by Evan able to clarify this for me. Evan simply says it does not happen, as if that's been settled. He does not mention the warming, for example, that would come from the (potentially sudden? would it even matter?) end of reflective fossil fuel aerosols.

The amazing lack of clarity on this subject, which is absolutely crucial to the discussion of any need to lower emissions, is astonishing, and leads cynical people like me to assume that it is a result of the IPCC-induced obfuscation and the complete ineptitude on the part of scientists to recognize that this issue is important and to do something about providing clarity.

A Frank Discussion About the Propagation of Measurement Uncertainty

bigoilbob at 02:39 AM on 20 August, 2023

"Do you have any link to specific statements from Carl Wunsch? Curiosity arises."

Specifically, this is what I found. Old news, but not to me. I hope that I did not mischaracterize Dr. Wunsch earlier, and my apologies to both him and readers if aI did so.

"#5 Carl Wunsch
I am listed as a reviewer, but that should not be interpreted as an endorsement of the paper. In the version that I finally agreed to, there were some interesting and useful descriptions of the behavior of climate models run in predictive mode. That is not a justification for concluding the climate signals cannot be detected! In particular, I do not recall the sentence "The unavoidable conclusion is that a temperature signal from anthropogenic CO2 emissions (if any) cannot have been, nor presently can be, evidenced in climate observables." which I regard as a complete non sequitur and with which I disagree totally.

The published version had numerous additions that did not appear in the last version I saw.

I thought the version I did see raised important questions, rarely discussed, of the presence of both systematic and random walk errors in models run in predictive mode and that some discussion of these issues might be worthwhile."

https://pubpeer.com/publications/391B1C150212A84C6051D7A2A7F119#5

Ice age predicted in the 70s

Don Williamson at 23:06 PM on 18 August, 2023

To Eclectic

Use Google Scholar as well as a couple of search engines reading peer-reviewed paper on the 'hiatus' 'wsrming slowdown'

If you jot down the various reasons that were used in the multiple papers you'll understand why Dr Michael E Mann said, "The problem isn't that we cannot explain the temporary slowdown in warming — ???????????? ???????????????????????????? ???????? ???????????????? ???????????????????? ???????????? ???????? ???????????????? ???????????????????????????????????????????????? ???????????? ????????"

Dr Kevin Trenberth Trenberth was a co-author on a paper published in Nature Climate Change that used models to show that pauses in surface temperature warming correspond to additional heat being stored deep in the ocean, ???????????????????? ???????????????????? ???????????????? ???????? ???????????? ???????????????????????????????? ???????????????????????????? ???????????????????????????????????? ????????????????????????????.

The 'warming' was taking place where there's little to no measuring devices?

Is that sound science?

link to quotes above:

https://www.scientificamerican.com/article/has-global-warming-paused/

????

It's not bad

Bob Loblaw at 01:05 AM on 16 August, 2023

Jlsoaz:

Studies of excess heat deaths, etc, run into a common problem in epidemiology: you can't do controlled experiments, and analysis of data requires a rather convoluted mix of causes that need to be isolated through various models. In the end, you get probabilities, not explicit cause-effect relationships.

Even in a "simple" autopsy, the cause of death is often a series of factors that combined to yield a fatal result. Did Covid cause that death? Well, he was elderly, had COPD and diabetes. The death certificate says his heart gave out. But he was living with those diseases and had prospects for many more years of life until Covid came along and hit him.

The tobacco industry used this limitation to great effect: "you can't prove that this person got this cancer from smoking our cigarettes", etc.

That's not to say that you suggestion is without merit. It will be considered, but I"m not sure how we might go about it.

A Frank Discussion About the Propagation of Measurement Uncertainty

MA Rodger at 18:52 PM on 11 August, 2023

Nigelj @13,
The paper Frank (2019) did take six months from submission to gain acceptance and Frontiers does say "Frontiers only applies the most rigorous and unbiased reviews, established in the high standards of the Frontiers Review System."
Yet the total nonsense of Frank (2019) is still published, not just a crazy approach but quite simple mathematical error as well.

But do note that a peer-reviewed publication does not have to be correct. A novel approach to a subject can be accepted even when that approach is easily show to be wrong and even when the implications of the conclusions (which are wrong) are set out as being real.
I suppose it is worth making plain that peer-review can allow certain 'wrong' research to be published as this will prevent later researchers making the same mistakes. Yet what is so often lost today is the idea that any researcher wanting publishing must be familiar with the entirety of the literature and takes account of it within their work.

And for a denialist, any publication means it is entirely true, if they want it to be.

In regard to the crazy Frank (2019), it is quite simple to expose the nonsense.

This wondrous theory (first appearing in 2016) suggests that, at a 1sd limit, a year's global average SAT could be anything between +0.35ºC to -0.30ºC the previous year's temperature, this variation due alone to the additional AGW forcing enacted since that previous year. The actual SAT records do show an inter-year variation but something a little smaller (+/-0.12ºC at 1sd in the recent BEST SAT record) but this is from all causes not just from a single cause that is ever accumulating. And these 'all causes' of the +/-0.12ºC are not cumulative through the years but just wobbly noise. Thus the variation seen do not increase with variation measured over a longer period. After 8 years in the BEST SAT record is pretty-much the same as the 1-year variation and not much greater at 60 years (+/-0.22ºC). But in the crazy wonderland of Pat Frank, these variations are apparently potentially cumulative (that would be the logic) so Frank's 8-year variation is twice the 1-year variation. And after 60 years of these AGW forcings (which is the present period with roughly constant AGW forcing) according to Frank we should be seeing SAT changes anything from +17.0ºC to -12.0ºC solely due to AGW forcing. And because Frank's normal distributions provides the probability of these variations, we can say there was an 80% chance of us seeing global SAT increases accumulating over that 60 years in excess of +4.25ºC and/or decreases acumulating in excess of -3.0ºC. According to Frank's madness, we should have been seeing such 60-year variation. But we haven't. So as a predictive analysis, the nonsense of Frank doesn't begin to pass muster.

And another test for garbage is the level of interest shown by the rest of science. In the case of Frank (2019), that interest amounts to 19 citations according to Google Scholar, these comprising 6 citations by Frank himself, 2 mistaken citation (only one by a climatological paper which examines marine heat extremes and uses the Frank paper to support the contention "Substantial uncertainties and biases can arise due to the stochastic nature of global climate systems." which Frank 2019 only says are absent), a climatology working-paper that lists Frank with a whole bunch of denialists, three citations by one Norbert Schwarzer who appears more philosopher than scientist, and six by a fairly standard AGW denier called Pascal Richet. That leaves a PhD thesis citing Frank (2019)'s to say "... general circulation models generally do not have an error associated with predictions"
So science really has no interest in Frank's nonsense (other than demonstrating that it is nonsense).

A Frank Discussion About the Propagation of Measurement Uncertainty

Eclectic at 10:44 AM on 9 August, 2023

There is a 2017 YouTube presentation by by Dr Patrick T. Brown (climatologist) which is highly critical of Dr Patrick Frank's ideas. The video title is:- "Do 'propagation of error' calculations invalidate climate model projections of global warming?" [length ~38 minutes]

This video currently shows 7235 views and 98 comments ~ many of which are rather prickly comments by Patrick Frank . . . who at one point says "see my post on the foremost climate blog Watts Up With That" [a post in 2015?] # Frank also states: "There's no doubt that the climate models cannot predict future air temperatures. There is also no doubt that the IPCC does not know what it's talking about."

Frank has also made many prickly comments on WUWT at various other times. And he has an acolyte or two on WUWT who will always denounce any critics as not understanding that uncertainty and error are not the same. [And yet the acolytes also fail to address the underlying physical events in global climate.]

In a nutshell : Dr Patrick Frank's workings have a modicum of internal validity mathematically, but ultimately are unphysical.

CO2 effect is saturated

Eclectic at 08:32 AM on 3 August, 2023

[ If the Moderator will allow a brief off-topic musing, I promise a sort of return in my concluding paragraph. ]

As a complete tyro in the world of probabilistic AI language generative models, I picture ChatGPT as the analogy of a Zillion monkeys tapping away at a Zillion typewriters . . . and eventually (which is actually a millisecond) out comes something speciously good. The product is sometimes Booker Prize standard; sometimes merely quite presentable; sometimes a diamond but deeply flawed when examined closely; and sometimes there is an Einsteinian Pearl of inventiveness (if the reader has the wit to pick it up and run with it). But always, the winning monkey has no real knowledge of what he has produced. Play-It-Again-Sam . . . and a millisecond later, the new winning monkey gives you a somewhat different product. ~In a decade's time, will the current language AI become so refined as to filter out its own fabrications & nonsenses? Probably yes...

On-topic ~ another analogy is the brain of the climate-science-denier, whose Motivated Reasoning (produced by a Zillion monkey neurons) keeps coming out with flawed presentations, in various repetitions. Monkeys, or Dragons?

CO2 effect is saturated

Eclectic at 19:41 PM on 2 August, 2023

Welcome back, DragonsHeads / DragonHeads / DragonSeed / DragonTeeth... It appears you have enlisted the aid of ChatGPT or Bard or other Artificial Intelligence "large language models", to construct your post #704.

ChatGPT etcetera typically produce a lot of words, with an initial semblance of meaning . . . but on closer examination, the words can often fail to show a true connection with reality ~ and that is the case here. DragonChat, you are spouting nonsense. Come back in 2030, in your seventh iteration ! [ Meanwhile, you might enjoy exercising yourself at the website WattsUpWithThat ;-) ]

Moderator ~ you are too quick on the draw !

Wildfires are not caused by global warming

Scott at 02:48 AM on 31 July, 2023

Eclectic @14 /Bob Loblaw @13 You are correct, I assumed the diagram was from the IPCC, it isn't, and the increase it shows has very little to do with global warming. In that respect it is extremely misleading. The area burnt by wild fires has been decreasing not increasing. You criticised this conclusion as being from 2016 - yet in a 2020 blog post by the Royal Society the authors of the paper were interviewed again to find out whether things have changed since its publication. The answer was basically no. "... when considering the total area burned at the global level, we are still not seeing an overall increase, but rather a decline over the last decades. This has been confirmed in a series of subsequent studies, using data up to 2017 or 2018."
royalsociety.org/blog/2020/10/global-trends-wildfire/

From: 'Large Variations in Southern Hemisphere Biomass Burning During the Last 650 Years' Z. Wang,1 J. Chappellaz,2 K. Park,1 J. E. Mak1 (Science Vol 330 17 December 2010)

"These observations and isotope mass balance model results imply that large variations in the degree of biomass burning in the Southern Hemisphere occurred during the last 650 years, with a decrease by about 50% in the 1600s, an increase of about 100% by the late 1800s, and another decrease by about 70% from the late 1800s to present day."
Southern hemisphere biomass burning

[For some reason images are not showing in the preview but the source is correct]

The same picture is repeated globally. In 'Climate and human influences on global biomass burning over the past two millennia' by J. R. MARLON et al. (Nature Geoscience 1, 697–702; published online: 21 September 2008), they measure sedimentary charcoal records spanning six continents to document trends in both natural and anthropogenic biomass burning for the past two millennia. From this they obtain the following graph - again showing a very clear 20th century decline.

GlobalBiomassBurning

All this begs the question of why there has been such an increase in fires in California.
"Autumn and winter Santa Ana wind (SAW)–driven wildfires play a substantial role in area burned and societal losses in southern California. Temperature during the event and antecedent precipitation in the week or month prior play a minor role in determining area burned. "

"Models explained 40 to 50% of area burned, with number of ignitions being the strongest variable. One hundred percent of SAW fires were human caused, and in the past decade, powerline failures have been the dominant cause. Future fire losses can be reduced by greater emphasis on maintenance of utility lines and attention to planning urban growth in ways that reduce the potential for powerline ignitions."

See 'Ignitions explain more than temperature or precipitation in driving Santa Ana wind fires' by Jon E. Keeley et al. Science Advances 21 Jul 2021 Vol 7, Issue 30

In 'Nexus between wildfire, climate change and population growth in California' by Jon E. Keeley and Alexandra D. Syphard (Fremontia vol 47 Issue 2 2020) is a detailed analysis of wildfires in California. A distinction is drawn between fuel dominated and wind dominated fires.
FireCause

Population increase leading to urban expansion, accompanied by expansion of the electric power grid, increasing the chances of a powerline failure was a significant cause of wildfire. (The 2021 Dixie fire at 389,837 hectares was caused by a tree falling onto a powerline and could have been prevented had the power company acted promptly - see California Department of Forestry and Fire Protection, Investigation Report Case Number: 21CABTU009205-58). General poor maintenance by utilities has caused many wind dominated wildfires.

Fuel-dominated fires are mostly forest fires in lightly populated regions and so tend to result in less property damage. A century of fire suppression has led to a huge accumulation of fuel at ground level. As a result a low intensity surface fire can easily become a high intensity crown fire.

How 100 years of a misguided policy outlawing controlled burns has left California vulnerable to wild fires
www.theguardian.com/us-news/2019/nov/21/wildfire-prescribed-burns-california-native-americans

www.reuters.com/world/us/california-is-meant-burn-experts-teach-landowners-art-prescribed-burns-2023-06-01/

In conclusion, the total area burnt has been decreasing globally and in California where it has increased this is largely due to misguided policies of forest management and poorly maintained, overloaded power infrastructure. (Urban planning which doesn't adequately address fire hazard doesn't help either). I think linking wildfires to global warming is misguided and likely to backfire when it is revealled to be the least important factor.

How big is the “carbon fertilization effect”?

daveburton at 08:56 AM on 13 July, 2023

Rob, in answer to your first question, Bob is correct: they use different units.

Both the graph and the "plug in suitable values" calculation (above) are for freshwater, but that hardly matters. CO2 is noticeably less soluble in saltwater, but the effect of temperature on CO2 solubility is nearly identical. Here's the same calculation with salinity 35 (typical seawater), for a 1° temperature increase (from 288K to 289K):

1 - ( (e^( -60.2409 + (93.4517*(100/289)) + (23.3585* ln(289/100)) + 35 * (0.023517 - (0.023656*(289/100)) + (0.0047036 * (289/100)^2)) )) / (e^( -60.2409 + (93.4517*(100/288)) + (23.3585* ln(288/100)) + 35 * (0.023517 - (0.023656*(288/100)) + (0.0047036 * (288/100)^2)) )) ) =

Bob is also correct that ocean chemistry is more complicated than that, in part because most of the dissolved CO2 immediately dissosiates into various ions. Here's a good resource on ocean chemistry:
http://www.molecularmodels.eu/cap11.pdf

What's more, in the oceans, biology generally trumps chemistry, and that is certainly true for CO2 uptake. Some people think that the capacity of the oceans to take up CO2 is limited to surface water by ocean stratification. But that's incorrect, beause the "biological carbon pump" rapidly moves CO2 from surface waters into the ocean depths, in the form of "marine snow."

The higher CO2 levels go, the faster that "pump" works. Here's a paper about it:
https://www.science.org/doi/reader/10.1126/science.aaa8026

Once carbon has migrated from the ocean surface to the depths, most of it remains sequestered for a very long time. Some of it settles on the ocean floor, but even dissolved carbon is sequestered for a long time. For instance, it is estimated that the AMOC takes about 1000 years to move carbon-rich water from high latitudes to the tropics, where it can reemerge. That is obviously far longer than the anthropogenic CO2 emission spike will last.

Due to the temperature dependence of Henry's Law, a 1°C increase in temperature slows CO2 uptake by the oceans by about 3%. That's a slight positive feedback: more CO2 in the air increases water temperatures, which slows ocean uptake of CO2. But it is very minor, because a 50% (140 ppmv) rise in atmospheric CO2 concentration accelerates CO2 uptake by the oceans by 50%, which obviously dwarfs 3%. That's the main reason that ocean uptake of CO2 continues to accelerate despite the temperature dependence of Hanry's Law.

Water vapor is the most powerful greenhouse gas

Charlie_Brown at 03:13 AM on 18 June, 2023

Bob @388
We agree more than you think. I did not intend to imply that only two atmospheric layers need to be considered for emittance. I was intending to illustrate the many strong and weak absorption lines in the layers that were most important for emittance from CO2 and H2O. A useful concept is to look down from the top of the atmosphere. Integrate absorptance/emittance for energy loss to space from the top and descend until a value of 1.0 is reached. MODTRAN Infrared Light in the Atmosphere (MILIA) model, which is a multilayer model, does the calculations.

Maybe we disagree on descriptions for the magnitude of contribution to the upward heat flux from the tropopause and the stratosphere, because I conclude that the major emitting layer for CO2 is the tropopause (11-20 km in the 1976 U.S. Std atmosphere) and the stratosphere contributes only a small amount. This can be demonstrated by changing the altitude in MILIA from 20 km (217 K) to 50 km (271 K). At 20 km, the bottom of the spectrum in the CO2 band of 14-16 microns reaches 217 K, which matches the Planck distribution. Raising the altitude to 50 km brings the bottom of the band up a little bit to 222 K, but not to the higher temperature of the stratosphere. Also, and very interesting, is the appearance of a sharp peak at 14.9 microns that matches a Planck temperature of 240 K. This is caused by the contribution from a few very strong CO2 absorption lines.

We agree that Manabe’s work is awesome, but I don’t think that it necessarily supports a description “A lot of IR loss to space comes from the stratosphere.” It demonstrates a significant effect of CO2 on the temperature of the stratosphere. However, the stratosphere has so few molecules that small differences in the total IR energy flux can have large differences in temperature.

Water vapor is the most powerful greenhouse gas

Charlie_Brown at 07:47 AM on 16 June, 2023

Actually, I think that Vidar2032 @383 is correct. When he/she says GHGs emit at a fixed temperature, I believe he/she means at the temperature of the atmosphere as fixed by the atmospheric temperature profile. The 1976 U.S. Std Atmosphere for the tropopause, where CO2 emits to space, is close to 220K, while the emitting layer of H2O vapor in the troposphere is about 240-270 K. When he/she says that the effect of increased concentration is to broaden the band, that also is correct when considering that increasing concentration strengthens weak absorption lines. Look at the Figure in Bob Loblaw @7 in his linked thread to Beer’s Law above, which Bob kindly produced for me at that time. The weak absorption lines on the wings get stronger as concentration increases. There is sufficient path length in the tropopause to bring most of the absorption lines for the CO2 band between 14-16 microns close to 1.0, which means that the emittance is close to 1.0. Stacking the strong absorption lines in the middle of the band, which means increasing the path length and bringing an emittance of close to 1.0 even closer to 1.0, is not how increasing CO2 increases the emittance. Note that increasing emittance means more energy is emitted from a colder temperature which has less intensity than the energy emitted from a lower altitude at a warmer temperature. This is in accordance with the Planck black body distribution curves that Bob presents. The difference between a black body and a gas is that a black body absorbs/emits at all wavelengths while gases absorb/emit only at wavelengths specific to their molecular structure. What would be interesting, if only I could post my own Figure, would be the HITRAN absorption lines for CO2 at conditions of the tropopause and H2O for the troposphere.

Meanwhile, Vidar’s question is an excellent opportunity to use the Univ of Chicago link to MODTRAN Infrared Light in the Atmosphere. Choose the 1976 U.S. Std Atmosphere. All one has to do is increase the water vapor scalar to 1.07 to show a 7% increase, then adjust the temperature offset until the original value is matched. It turns out to be about 0.25 C. Better, to see if 7 % is about right, set CO2 to 280, CH4 to 0.7, and Freon to 0 to get pre-industrial conditions. Save the run to background. Then change CO2 to 415, CH4 to 1.8, and Freon to 1.0 to get current conditions, adjust the temperature offset to match the starting value, and choose holding fixed relative humidity. The raw model output shows that it changes the water vapor by about 6%, and the temperature offset is about 1.0 C. It's a very good approximation, but be careful not to place too high of an expectation on the accuracy and precision of this model. Realize that it is designed to be an educational tool with high computational speed and limited flexibility that provides good results, but better models exist for professional use.

2nd law of thermodynamics contradicts greenhouse theory

Philippe Chantreau at 10:05 AM on 14 June, 2023

Liikeitwarm,

I think you have a lot of misconceptions about what is known and understood about IR behavior in the atmosphere and what is not. This is an extensively researched subject, it has produced results used in many engineering fields that require precision and reliability. You need to peruse through Iacono and Clough (1995) and take a long studious look at the famous graph that is in that paper. Then look at the work that has been done since. IR absorption and re-emission is thoroughly modeled by the MODTRAN line by line model and to an even finer degree by HITRAN. The full IR atmospheric profile is known. Accumulating GHGs raises the effective emission altitude. Do some reading about that too. MODTRAN is a major component of IR weapon guidance systems. The US Air Force holds patents on MODTRAN. They don't care about anyone's opinion or what is on this or that website.

This is one of these areas of knowledge where your opinions and beliefs (or anyone else's, for that matter) are of no importance whatsoever. All the heavy lifting has already been done, and there is a right answer: the physics-based theoretical calculations, painstakingly accumulated to form the line by line models, have been validated by measurements at all applicable altitudes. This is not an area of uncertainty that is the subject of significant scientific debate.

No matter what you think happens to IR radiation leaving the ground, what actually happens has been very well studied, very well quantified, and is based on physics. It is possible that a major discovery could revolutionize our understanding, but the practical consequences of it on this particular subject would be similar to that of general relativity on the workings of an internal combustion engine, i.e. negligible.

What does past climate change tell us?

Bob Loblaw at 12:15 PM on 7 June, 2023

Eddie @ 33:

Given that there is no single, simple hypothesis on which "anthropogenic global warming" is based, providing a simple example that would "falsify" it is a dishonest challenge.

The prediction of rising temperature in response to increased greenhouse gases is a logical consequence of many falsifiable aspects of physics. Just a handful, off the top of my head:

energy conservation

radiation theory (many sub-theories)

CO2 gas absorbs and emits IR radiation at wavelengths that occur on earth.

geophysical fluid dynamics

gravity

etc.

By "computer models", I assume that you mean models such as general circulation models used to simulate global climate. Such models are really just "computer solutions to mathematical models". The mathematical equations in such models are many - and cover the many aspects of physics that are required. All of those equations are - in principle - falsifiable. All of them have strong evidence that they are reasonably correct - i.e., nothing has been observed that would falsify the theories that they describe.

What does past climate change tell us?

EddieEvans at 05:51 AM on 7 June, 2023

I've been asked to "falsify" anthropogenic global warming. I propose using computer models. Are such models available?

At a glance - How reliable are climate models?

Bob Loblaw at 00:25 AM on 3 June, 2023

Gootmud @ 41:

In the long-term, the "at a glance" is not intended as a stand-alone item. It's just the opening for the full rebuttal. Something more than a headline, but still something that is supposed to introduce the full article.

It sounds like you want something more like an abstract for a paper - something that very briefly introduces the subject and very briefly gives the answer. That could be a constructive improvement - something worth considering.

Full disclosure: I have not been active in the writing of these at-a-glance updates, although I am part of the SkS "team".

Keep in mind that the rebuttals here at SkS are responses to certain common myths found in the contrarian meta-world. The specific myth for this rebuttal basically comes down to an argument that models are completely useless. The Freeman Dyson quote at the top of the main article starts with "[Models] are full of fudge factors that are fitted to the existing climate..." Similar sentiments are often expressed more or less in the form "they just make the models do whatever they want". You don't need to show that climate models are perfect to dispute that myth - just show that there are (a lot of) things that they can do well.

Evaluating models is a complex process. A full-scale global climate model produces far more output than we actually have in weather/climate observations. Far more spatial resolution in temperature, humidity, wind speed, radiation, etc - both vertically and horizontally.

And global climate models are really an assembly of many other sub-models. A radiation model. A cloud formation model. A precipitation model. A fluid dynamics model. A surface evaporation model. (My background mostly focuses on microclimate models, incorporating surface conditions and soil temperatures.)

Each of these sub-models will undergo its own evaluation, usually on a localized scale where far more detailed observations are available and can be used to confirm proper model performance. Then, when all sub-models are integrated into a global climate model, more validation is done with global observations.

Often, the global climate model will contain simplified models, due to the need to run them for thousands of points at high temporal resolution for long periods of time. The simple models can be tested against the more complex models that have been validated against more detailed observations.

As you said: "reliable for what purposes?". There is no simple answer to quantify "reliability" under any circumstances, and even complex answers require an answer to that "what purpose?" question, first.

At a glance - How reliable are climate models?

Gootmud at 23:48 PM on 2 June, 2023

Bob @38: sorry, I'm finding that super confusing. If the at-a-glance section isn't meant to summarize the answer, I don't understand what it's for.

Or perhaps what's confusing is the answer it's summarizing? The basic answer seems likewise wide of the mark. It restates the quantitative question as more of a binary--do the models work or not?--and suggests they do as demonstrated by hindcasting. But then it shows a graph saying they're too conservative. And then it cites Hausfather's claim that 14 of 17 projections are indistinguishable (another binarization) from what actually occurred, which obviously leaves three others. I'm still left wondering...how reliable are climate models?

What would help is more discussion of how we should think about reliability, as that's the title's load-bearing characterization. Are models that are right 14 out of 17 times reliable? Reliable for what purposes?

At a glance - How reliable are climate models?

Eclectic at 23:45 PM on 2 June, 2023

Gootmud @ 33 etc ,

the OP title indicates a brief description of the subject. Nicht wahr?

If you wish an exhaustive description/analysis , then you must read further into the subject. But best if you first decide on exactly what you wish to obtain ~ do you wish for results that are adequately reliable for practical purposes [and evidently they are ] . . . or do you wish for some mathematical quantification of "reliability" (in which case you will need to produce some cutting-edge methodology for the assessment).

PSBaker @34 & elsewhere ,

There is a great deal of vagueness everywhere, to be sure ;-)

However ~ "Driving with a fuzzy view of the climatic road ahead . . . is better than driving into the future with eyes closed." [Or have I misremembered that aphorism by Sun Tzu ? ]

But for short-medium term purposes in agriculture (including coffee growing) . . . it is fuzzily unclear why you would criticize models of 30+ year resolution [i.e. "climate" ] for not being useful in the shorter term. And to quote again perhaps from Sun Tzu :-

~ "Do not be angry that an elephant is not the size of a mouse."

At a glance - How reliable are climate models?

Bob Loblaw at 22:55 PM on 2 June, 2023

PSBaker @ 34:

And your response is pretty much what I expected from you. You consider the people that put hard work into models that you admit "are good at some things", and call them "the priesthood who elect to guard the eternal flame".

The full rebuttal is pretty clear about the type of models being examined - global climate models. These are not designed to do everything, and never will be. Nobody ever has a "model of everything".

The examples you gave are very limited in scope, yet you have decided that "There’s a whole sub-industry of scientists applying them to make unrealistic projections."

You have dismissed my previous comments with the phrase "Much of your ire seems to be focussed on lack of specificity, vagueness etc." In comment #30, I gave specifics comments on what I read in the Nature Climate Change articles you referenced. You have not provided any response or rebuttal to those comments of mine.

For someone who claims "That... is what the discussion of climate models should be addressing", you seem to be very reluctant to actually engage is serious discussion of the references you supplied. Instead, you just call it "a particular snarky rage".

Given that you will be unlikely to actually engage in any discussion if I provide comments on the video you link to, I think I'll save my effort.

At a glance - How reliable are climate models?

Bob Loblaw at 22:33 PM on 2 June, 2023

Gootmud @ 33 and PSBaker # 34:

I will take those comments about lack of answers and vagueness in this specific post as a clear indication that neither of you have bothered to follow the links in this post to other posts that have additional details. The full "How reliable are Climate Models?" post has a basic and an intermediate tab with increasing level of detail.

I know that information about those extra details are hidden deeply in this post. You have to read all the way to the end of the very first paragraph in the green box at the top of this post to find where it says "Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there." And the actual links to 15 related SkS posts are also hard to find, being buried at the bottom under a big red heading that says "Click for further details".

[Still searching for that html sarcasm tag]

At a glance - How reliable are climate models?

PSBaker at 21:44 PM on 2 June, 2023

Goodness @Bob Loblaw @eclectic !
Much of your ire seems to be focussed on lack of specificity, vagueness etc …

Sorry, I didn’t realize there is some sort of rule about it … but if you look at the OP, it is a model of vagueness, no papers cited – frankly, it’s pretty much waffle.

In my response I did provide examples, albeit the first to hand. I could have done better, but since @eclectic stated “ . . . but uncertainties are, for the rest of us, probably not worth addressing” I felt that, together with the lack of specificity in the OP, this gave me some liberty to extemporize. I also did not want to finger specific papers since I know some of the scientists involved, who have enough problems trying to navigate their careers without feeling picked upon.

I’m not surprised by the response though, this has been my experience through the latter part of my career – that criticizing modelling evokes a particular snarky rage from the priesthood who elect to guard the eternal flame.

My central point however remains valid, the models are good at somethings, lousy at others and there’s a whole sub-industry of scientists applying them to make unrealistic projections. We who work in the field, trying to help (in my case poor farmers) find them of little use and even counterproductive.

That, in my humble opinion, is what the discussion of climate models should be addressing and what I, in my albeit halting fashion, was trying to convey.

Here’s Dr Baethgen covering some of these points better than I can, in a lecture from 2020, (start ~8 mins), esp. 18 & ~35m “So when you see these beautiful maps with reds and greens, don’t trust them, remember that behind that colour is a big uncertainty.”

https://worldcoffeeresearch.org/news/2020/watch-a-new-way-to-think-about-climate-change

At a glance - How reliable are climate models?

Gootmud at 21:32 PM on 2 June, 2023

So...how reliable are climate models? The title poses a quantitative question that the article never answers.

At a glance - How reliable are climate models?

Bob Loblaw at 06:01 AM on 2 June, 2023

PSBaker @ 15:

First, let's address your statement "I was not referring to..."

In your first comment (#1), you weren't referring to anything specific. You finished off with a broad, sweeping generalization about "senior scientists and journal editors". This gives the appearance that you are casting a wide net - as Eclectic said in comment #2 "unless you feel something misleading or nefarious is being concealed by their omission."

So, now that you have actually provided some specific references, let's look at them. Eclectic has already made some comment in #18, but I have a few more points to make.

For your first reference (link to full artcle):

Eclectic commented on the vagueness of much of the discussion. I tend to agree.

I also note that the key figure 2, on precipitation changes, makes what I would consider to be a fundamental error in the use of global climate model projections. It uses the multi-model mean as if it is the predicted path. It is not. In the figure I included in comment #8, the Model ensemble spread that gives a better indication of the possible future paths as predicted by the models.

In section 2.1, they talk about people often use an average from several models "so that only the trend remains", so they are aware of the issue, but then they went and used that same ensemble mean to do their analysis in figure 2.

In the first part of section 2, they actually state "Although the limitations of climate change projections are well-documented... the consequences of these limitations for practical decision-making in development practice have not been clearly laid out for the nonspecialist." [emphasis added]

I also note that the sentence from the abstract immediately preceding the one that you quote states: "Climate model projections are able to capture many aspects of the climate system and so can be relied upon to guide mitigation plans and broad adaptation strategies..."

Thus, your first reference is not a broad condemnation of climate models - and basically sounds like a cry that it's the fault of climate scientists that non-specialists don't pay attention to the well-documented efforts of those climate scientists to explain the limitations of climate models.

Now, for your two references to Nature Climate Change:

The Lembrechts one is a short News & Views article, and the first reference it contains is to the Maclean and Early paper (the other reference you provide). It hardly constitutes a second, independent analysis.

In the Maclean and Early paper, the data that they use to evaluate their microclimate approach (as opposed to a macro-climate approach that global climate models work with) uses two time periods: 1977-1995, and 2003-2021.

The changes in "heathland and grassland plant taxa" that they are looking at would not experience substantial change during that period, compared to the expected changes over the next century. The differences in range shift they get from their two modelling approaches are 14km (macro) and

The short time periods means that much of what they are modelling in the way of microclimate changes is going to be related to weather and short-term variability, not long-term major shifts.

A major weakness in their argument is that they basically present a case where short-term small changes in climate conditions do not lead to major range shift - but the concerns for future climate are not related to minor shifts that have already occurred. They are related to the major shifts expected in the future, and how they will be occurring much faster than species have adapted to in the past.

So, your second and third references also do not reflect on unreliability of global climate models.

P.S. The next time you want to post a comment similar to #1, please provide the references you are relying on in your first post. And as Eclectic has stated in #18, you should also be providing some sort of detail on what it in those papers that you think is relevant, and what point you want to make.

At a glance - How reliable are climate models?

Rob Honeycutt at 14:53 PM on 1 June, 2023

What's also clear, and is extensively discussed in each of the articles you've linked to, is the "models" being discussed are a subset of the ensemble mean. They're discussing a few of the models. They aren't saying all models run hot. Some actually run cool. And different model runs can run hot or cold. And modelers will often tweek the weighted balance of models to produce better results.

Before dismissing a major body of research because it doesn't conform to what you think it should do, perhaps it would be appropriate to do more research and perhaps even talk to an actual scientist who does modeling so you can better understand how they do their work.

Just a suggestion.

At a glance - How reliable are climate models?

Rob Honeycutt at 14:45 PM on 1 June, 2023

Don't just look at the headlines, Gordon. Read the materials in full.

It's clearly no "unfortunate" precisely because the models do a very good job. You are merely confusing scientists seeking ways to improve the models with thinking that means they're all bad. You're essentially motivated to throw the baby out with the bathwater.

The rebuttal states that models are not perfect.

At a glance - How reliable are climate models?

Gordon at 14:38 PM on 1 June, 2023

Rob @ 20

Lets just look at the headlines:

"Use of ‘too hot’ climate models exaggerates impacts of global warming" "Guest post: How climate scientists should handle ‘hot models’" "Climate simulations: recognize the ‘hot model’ problem"

I will restate that It's unfortunate that so much of the scientific literature relies on these models in making projections. This is especially true in light of the concerns that have been raised in the linked articles and the fact that these projections are used by policy makers to determine our future.

I fail to see in the rebuttal any mention that there is an issue with models running too hot - just that the models are not perfect. If the reverse was true and the models were running colder that the observational data would the rebuttal still be primarily about an issue of perfection ?

At a glance - How reliable are climate models?

Rob Honeycutt at 12:17 PM on 1 June, 2023

Gordon... "If there is an issue shouldn't it be addressed in this rebuttal?"

It is addressed in this rebuttal. It's clearly stated that, "Climate models are not perfect. Nothing is. But they are phenomenally useful."

That statement is appropriately inclusive of the points you're bringing up.

At a glance - How reliable are climate models?

Rob Honeycutt at 11:01 AM on 1 June, 2023

Gordon... I get the sense you didn't actually read those articles because they state that "some" of the models run hot, not that "models run too hot."

Zeke's article on Carbon Brief that you've linked is a good one to read.

Perhaps you're also not understanding the expectations of climate models. No one expects that climate models are going to give us a precise pathway for global temperature. What they are intended to do is inform us in a way that benefits our understanding of the climate system and the likely impacts of our behaviors.

I've seen many a climate modeler saying, "Models are always wrong, but observations of the future are currently unavailable."

Climate models have actually done a very good job of projecting future temperatures over the years. Here's another Zeke piece on that topic.

You started commenting using Christy's work and haven't attempted to defend it. You're pulling up other examples of modelers doing their work improving the skills of their field by openly discussing areas of concern and methods to address them. But out of that you're somehow concluding, erroneously, that, "It's unfortunate that so much of the scientific literature relies on these models in making projections."

Your statement there is bizarre because, well, how else would one make projections if not by using models? And, your conclusion that the models are poor reveals your motivated reasoning on the subject, when in truth the models are not poor. They're really incredibly good.

Can models get better? Absolutely.

Are models a waste of time and money? Clearly not since they've consistently proven to be accurate within the range of uncertainties necessary to inform us of the challeges we face with climate change.

At a glance - How reliable are climate models?

Gordon at 09:37 AM on 1 June, 2023

Rob @ 16

Why do science.org carbonbrief.org and nature.com all report that there is an issue with the models running too hot ? If there is an issue shouldn't it be addressed in this rebuttal ?

At a glance - How reliable are climate models?

Eclectic at 07:29 AM on 1 June, 2023

Doug Bostrom @17 ~ A good point. Very !

PSBaker @15 ~ it would be helpful if you gave more detail on the 3 papers you mention.

Your first paper (H.Nissan et al., 2019) appears very vague, and talks in a general way about farmers' need for medium term weather predictions wrt pesticide spraying scheduling and suchlike agricultural management. Also talks (slightly) about 30-50 year plannings for dam construction. Overall, the paper had such an unapt & vague manner, that I began to suspect the authors were using AI-generated [ChatGPT] . This was not helped by their mention of soil-moisture predictions in three disparate parts of Bangladesh, nor of vague reference to rainfall pattern prediction in Kenya/Somalia. PSBaker, your quoted extract from the paper provides little-to-nil relevance to global climate modeling . . . and yet you seem to be using the #15 quote to circle back to a disparagement of climate models. [ If this was not your intent, then please be very specific on the point you were wishing to make. ]

Your second paper ( J.J.Lambrechts 2023) was paywalled [for me] but a half-Extract talked of micro-climates in a manner that suggested the body of the paper was not relevant to global climate modeling. Remember, this thread is a computer climate model thread.

Your third paper (Maclean & Early, 2023) was similarly unapt . . . but the paper's body did provide some amusement :- "We model ... distributions of 244 heathland and grassland plant taxa using both macro- and microclimate data and project these distributions ... [regarding] improving protection of refugial populations within species' geographic range ..."

Refugial populations of humans ~ would be more relevant to this thread.

At a glance - How reliable are climate models?

PSBaker at 18:38 PM on 31 May, 2023

@ Bob Loblaw 8: I was not referring to contrarian sources, nor the global models of which you give an example.

Read Nissan’s et al paper to see what I mean DOI: 10.1002/wcc.579 “Climate models are unable to represent future conditions at the degree of spatial, temporal, and probabilistic precision with which projections are often provided, which gives a false impression of confidence to users of climate change information.”

Or more recent critiques

https://www.nature.com/articles/s41558-023-01632-5

https://www.nature.com/articles/s41558-023-01650-3

At a glance - How reliable are climate models?

nigelj at 17:19 PM on 31 May, 2023

Gordon @10

The IPCC WR5 projection in your comments includes observational data from 1970 - 2012 only. Its old data possibly from an older IPCC report. The observational data is quite close to the modelling for much of that period but the years 2005 - 2012 (approx) in that graph clearly fall significantly below the modelling mid line prediction. But this is a relatively short time frame, and it represents short term natural variation that models can't fully predict in terms of timing. This is the alleged pause in surface temperatures, which amounted to a flat period in the warming trend of about 7 years and was due to the influence of natural variation ( in simple terms)

The graph posted by Bob Loblow @ 8 includes observational data from 1970 - 2022 and so its much wider and more recent data, and its obvious that the warming trend from 2012 - 2022 has swung back to near the model mid line prediction, and that the observational trend is tracking quite close to the modelling overall for the full period 1920 - 2022. The modelling is obviously not running significantly hot.

I'm surprsied you didn't notice any of this.

At a glance - How reliable are climate models?

Gordon at 15:19 PM on 31 May, 2023

Ron @11 similar insofar as the models are running hotter than the observed temperatures.

At a glance - How reliable are climate models?

Bob Loblaw at 11:48 AM on 31 May, 2023

PSBaker @1:

You need to stop reading contrarian sources that ignore the uncertainties that the scientists are presenting and try to pretend that it is the scientists that are ignoring the uncertainties.

Here is a recent RealClimate post that compares models and observations. They update it each year.

Here is the main figure from that post. Notice how it has a shaded area showing the "Model ensemble spread"? Is that too "hidden"?

RealClimate model comparison

You may also wish to read the links and look at the graphs I have presented above, in response to Gordon.

At a glance - How reliable are climate models?

Bob Loblaw at 11:40 AM on 31 May, 2023

Oh, and if you want to read about how unreliable Christy's satellite temperature data has been over the years, read about it here and take a look at this graphic showing how often Christy has had to fix errors:

Christy MSU corrections

At a glance - How reliable are climate models?

Bob Loblaw at 11:27 AM on 31 May, 2023

Gordon @ 5:

Congratulations on exposing the sources you are using for your comments here. It is unfortunate that so much of the "contrarian" talking points keep going back to the same unreliable sources.

This looks like another variation of a diagram from John Christy's flawed work, which has been debunked many times before. It is even featured in the Models are unreliable page that this short "at a glance" is updating. It is unfortunate that people like you can't be bothered to read the full blog posts you are challenging.

Here is the figure from that SkS page:

Christy misleading graphs

Here are a couple of RealClimate posts on the matter:

From 2016

From 2017

...and the key figure from those posts.

Christy misleading graphs

At a glance - How reliable are climate models?

Gordon at 10:48 AM on 31 May, 2023

How reliable are computer models ?

According to the chart below - not very !

Its unfortunate that so much of the scientific literature relies on these models in making projections.

At a glance - How reliable are climate models?

John Mason at 22:59 PM on 30 May, 2023

PSBaker #1 - yes rainfall can be difficult, especially when convection is involved! Dynamic rainfall along fronts models far better in my experience - less ingredients needed.

Looking for ways to explain uncertainty is certainly important because lay-folk tend to see things in black and white, whereas uncertainties drive science forward. This is a point that needs making repeatedly as it crops up.

At a glance - How reliable are climate models?

PSBaker at 19:42 PM on 30 May, 2023

Agree that temperature models are v useful especially at the global level, in fact they have been amazingly accurate. Less useful are rainfall models; I’ve seen examples of backcasting which are hopeless.

And as models are downscaled, uncertainties increase; when they’re used to predict future species distributions for instance, there are many uncertainties. It’s fine if everyone understands this but the problem is that such uncertainties tend to be downplayed, especially when a popular account appears.

This is exacerbated by the beautifully created, highly coloured and smoothed maps that can appear without any indication of errors/uncertainties, and these can rapidly become a credible reality – but the map is never the territory.

Some modellers get very prickly if you point this out but I think senior scientists and journal editors should be more diligent in ensuring such uncertainties are clearly stated, though of course this makes for a less relatable message to non-specialists.

Antarctica is gaining ice

Bart Vreeken at 19:51 PM on 24 May, 2023

Thank you very much, scaddenp #579

So text was just removed, which is very annoying! I wasn't sure if I had done anything wrong myself.

But indeed, a rising air temperature and reduced sea ice mean more snowfall and a higher Surface Mass Balance according to multiple models. The question is how that relates to the increased melting and calving along the edges. Nobody knows exactly, and therefore it's good to have a close look on what happens.

Antarctic surface climate and surface mass balance in the Community Earth System Model version 2 during the satellite era and into the future (1979–2100)

BL #577 "He's made a big thing about NASA's 149 Gt/yr value"

Huh ...? I simply changed the number, for it was wrong. Bob Loblaw was the one who kept talking about it. And yes, "it ignores all the data in between." But that's not what the discussion was about. Replacing the 'last-first' by 'regression' doesn't make it better, for that still ignores all the data in between.

EGU2023 - Highlights from the last week of April

John Mason at 22:00 PM on 28 April, 2023

My take on Friday so far: Baerbel has already covered sessions where we were both present above.

I particularly enjoyed CL1.1.4: Deep-time climate change: insights from models and proxies. This session provided a wide-ranging series of palaeoclimate studies looking at various parts of and the whole Earth at key points in the past such as the Permo-Triassic transition, the K-T extinction and the early Cenozoic hyperthermals.

Some topics were more familiar than others, for example looking at the selective nature of the K-T extinction interval in the oceans: the post-impact 'winter' actually had a positive effect on e.g. siliceous diatom productivity whereas the Deccan Traps large Igneous Province was mostly negative in that instance. Calcareous planktom however suffered greatly. The most though-provoking presentation, "Resilience and implications of an Antarctic monsoon during the Eocene", was something I had not looked at before. It appeasrs there were local ice-sheets even then, but unlike today the continent's periphery supported dense forest.

It's refreshing to be with so many people to whom the key principles of climate forcings are no longer argued over but instead it's the increaingly minute details of past climates that are under investigation and being presented.

One word on presentations: it's a pity that presentation skills are not taught at final year undergraduate level. I've seen talks varying from absolutely outstanding to hard-to-follow this week. The cause of the difficulty variably includes talking at breakneck speed about highly complex topics, large blocks of text in slides too long to read for their display-time and using too small a font size to even screengrab effectively. Some, by no means all people need to learn how to communicate findings more clearly (the EGU Guidelines are quite specific in this respect) and in addition, every author had a Supplementary Material folder in which to upload a more detailed file. Attention to such points would have made an aleady enjoyable event even more so!

Drastic climate action is the best course for economic growth, new study finds

One Planet Only Forever at 12:46 PM on 26 April, 2023

I am pleased to see more economists are developing a more comprehensive and realistic accounting of the ‘current day costs of being less harmful’ and ‘the future costs of harm done by harmful current day activities’. Economic evaluations of the ‘perceived current benefits obtained from causing increasing future climate harm’ vs. ‘reducing the harm done’ needed to move away from the Nordhaus style of significantly discounting the ‘future harm done’ toward the more ethically sensible Stern style of evaluation which, by using a lower discount rate, is more concerned about harm done to future generations.

“The Choice of Discount Rate for Climate Change Policy Evaluation” is a 2012 Discussion Paper that comprehensively presents the case for using lower discount rates. Longer term evaluations require lower discount rates, especially if there are harmful future consequences. Quotes from the paper and related points:

In the Introduction “Using his own DICE model, Nordhaus indicated that the differences between the Stern-endorsed and Nordhaus-supported discount rate accounted for all of the difference between the more aggressive climate policy endorsed by Stern and the considerably more modest effort supported by Nordhaus.” The Stern-endorsed discount rate was 1.4%. The Nordhaus-supported discount rate was 4.3%.

In 3a. The Social-Welfare -Equivalent Discount Rate “The choice of ‘social welfare discount rate’ is largely, if not entirely, based on ethical considerations: how much future well-being should count relative to current well-being in the social welfare function.” The Stern evaluation used a 0.1% social welfare discount rate. The Nordhaus evaluation used a 3% social welfare discount rate.

Even the evaluation discussed in this article is from the perspective of a less ethical economic evaluation that is limited to the financial items that are easy to quantify and enter into the ‘economic models’. An example is the statement that “Achieving such rapid decarbonization would require climate policies commensurate with a global carbon price of about $250 per ton of carbon dioxide today but declining to below $40 per ton in 2100 as the prices for clean technology come down.” There is no ethical reason for high carbon prices to be reduced in the future. The ethical requirement is for the harmful impacts to be ended, not to have them continue to be in the competition for popularity and profit in an ‘economically fair way’. (Note: even the 2012 paper I linked to above is 'ethically neutral' even though it presents the case for using lower discount rates which is more aligned with ethical considerations).

It is simply unethical for ‘Some people’ to benefit from causing harm that ‘others’ experience and have to try to deal with and repair. A continuously increasing price on carbon is one of the many mechanisms that need to be imposed to achieve the required correction of harmful developed activity, especially the correction of developed popularity and profitability of harmful over-consumption. And a Zero discount rate, and potentially a negative discount rate (increasing the evaluated cost of future harm being created), is probably more appropriate.

There is no consensus

Rob Honeycutt at 10:29 AM on 20 April, 2023

@933... Missed this one: "The only 'evidence' for the positive feedback theory are models which are trying to model something where many variables are only guesstimates."

Incorrect.

Knutti and Hegerl (2008)

There is no consensus

Albert at 09:26 AM on 20 April, 2023

"Dismissing feedbacks is an assertion of blind faith in the face of overwhelming evidence to the contrary. You just have to read the body of research."

I haven't dismissed any feedbacks, only the belief that they can be accurately measured. Many scientists believe that the positive feedback theory because of any temperature change in the atmosphere is grossly overstated and some even think the feedback is negative.

The only "evidence" for the positive feedback theory are models which are trying to model something where many variables are only guesstimates.

I programmed process computers for over 20 years and have a reasonable understanding of how models work.

If you you gave me the source code and runtime variable values of any model that purports to ""prove" positive feedback theory, I could show you in a short period of time that by adjusting these variables, any desired output could be achieved.

There is no consensus

Albert at 20:54 PM on 19 April, 2023

"The direct effect from CO2 is, as you say, ~1.2°C but you can't just reject physics and say there wouldn't be feedbacks. The feedbacks are very well known"

Not true. Even a basic knowledge of the complexity of modelling feedback would tll that it is impossible to model or prove.

it cannot be replicated in the lab or models, and any so called proof can easily be shown to be nit true.

if you know the basics of feedback theory you would know that the output to any given input has to be known precisely otherwise you cannot determine anything.

To give just one example, increased evaporation causes clouds and precipitation and there Are many scientists who believe that the feedback can only be negative or else there would be an exerthermic runaway.

but if you believe that feedbacks are "well known" pleas provide an exampl that is not ambiguous.

CO2 effect is saturated

Bob Loblaw at 00:19 AM on 25 March, 2023

Gootmud @ 680 - you said:

An excited CO2 molecule will lose its energy by bumping into an N2 or O2 molecule before it can radiate it away. Around the tropopause there's a laser effect, in which CO2 radiation stimulates other CO2 molecules to emit their own radiation, so more CO2 means more radiation transfer.

To expand on what MA Rodger says in comment 684, your first sentence is almost correct. Nearly all absorbed radiation energy will be lost thermally to surrounding molecules - but a very small proportion will be emitted as radiation again. As has been mentioned in previous comments here, there is a good description of the time constants involved at Eli Rabett's blog.

Your second sentence is not so correct. Nearly all energy that is used to emit radiation in the atmosphere comes from the reverse of your first sentence: CO2 or other greenhouse gas molecules gain energy by collision with other molecules. Again, most of that will be lost by thermal collisions with other molecules, but a small amount will be emitted as radiation. As the temperature rises, more thermal energy is transferred by collisions, and more will be emitted as radiation.

This dance between IR absorption, thermal collisions, and IR emission occurs at all levels in the atmosphere, not just the tropopause.. At each level, the exact quantities in each energy flow will depend on local temperature. You also get vertical energy transfer through convection. The overall temperature profile depends on a balance of all these energy flows.

All this is incorporated into climate models. It is not news.

The feedback question is important - distinguishing the "no feedbacks" response to doubling CO2 from the total response when proper feedbacks are included.

I suggest you read a previous comment of mine in this thread for more information and links to two relevant papers from the 1960s. (Like I said: this is not news.)

The Big Picture

Eclectic at 04:16 AM on 20 March, 2023

Gootmud @109 ,

you seem very alarmed at the imminent prospect of Earth's oceans freezing over or becoming boiling hot. Have you been reading alarmist blogs such as Dr Judith Curry's ? . . . or the even less scientific WattsUpWithThat ? Warning ~ those "contrarian" sources are lacking in common sense.

And there is no need for you to be alarmed about climate scientists using "models". The scientists are not clueless about Earth's future climate ~ they are guided by a good knowledge of basic physics plus knowledge of Earth's climate responses to altered Greenhouse Gas levels in the past millions of years. And also by recent responses to volcanic aerosol events and minor fluctuations in solar output.

No models are required to get a straightforward understanding of how climate changes occur. Please feel more relaxed, and take the time to educate yourself from genuinely scientific sources.

But you need to be careful not to be fooled by the many BS sources (such as Curry's or the WUWT mentioned above).

The Big Picture

Gootmud at 03:49 AM on 20 March, 2023

MA Rodger @110, saturation is already here. More CO2 can't make the sky much darker than it already is within its absorption bands.

Negative feedback effects and magnetic fields are likewise neither magic nor speculative. They're demonstrably real physical phenomena, just like the greenhouse effect. Figuring out how all these factors interact to create warming or cooling climate is a dizzyingly complex job that can only be attempted with computer models.

The Big Picture

MA Rodger at 02:20 AM on 20 March, 2023

Gootmud @109,

CO2 will not "saturate" prior to the planet warming to ridiculously high levels. The potential for some magic negative feedbacks to counteract further GHG warming or for some magnetic field effect to appear is lower enough to be ignorable. And I don't see why you need complex models to tell you that.

The Big Picture

Gootmud at 01:05 AM on 20 March, 2023

Eclectic and John Mason @104

We do need models to predict whether it will keep on warming. As CO2's absorption spectrum saturates, it can't trap more heat. Negative feedback effects like clouds might nullify any warming. Temperatures might drop due to independent effects like magnetic field changes much more influential than the greenhouse effect. We might be at 600ppm, freezing, and looking for ways to warm the Earth and slow the advancing ice.

Without models that account for all these effects, we.know nothing about future temperatures. We don't know ranges of likely changes. We don't even know the sign. A model need not be perfect--no model is ever perfect--but it must be representative of all the relevant physics if we are to trust its output.

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