You are calculating 2XCO2 as resulting in +4.5°C to +5.5°C of warming. Which seems bad enough.
Are you aware of the recent paleoclimate analysis that indicates warming is approximately +8°C for each doubling of CO2?
CR94 - It’s looking like each "CO2 Doubling” causes +8°C of warming. The 1st doubling was +180ppm to +360ppm. That takes us to +2°C. The NEXT doubling to +720ppm takes us to +10°C. Hansen puts us at +520ppm(e) right now.
A 485-million-year history of Earth’s surface temperature - Science, 20 Sep 2024, Vol 385, Issue 6715, DOI: 10.1126/science.adk3705
Judd et al. present a record of GMST over the past 485 million years that they constructed by combining proxy data with climate modeling (see the Perspective by Mills). They found that GMST varied over a range from 11° to 36°C, with an “apparent” climate sensitivity of ∼8°C, about two to three times what it is today.
The GMST-CO2 relationship indicates a notably constant “apparent” Earth system sensitivity (i.e., the temperature response to a doubling of CO2, including fast and slow feedbacks) of ∼8°C, with no detectable dependence on whether the climate is warm or cold.
I postulate that since 180ppm CO2 seems to be "rock bottom" for CO2 levels over the last 485my it should be used as our "starting baseline" rather than the arbitrary 280ppm present in 1850.
This results in the following:
The “first” 2XCO2 is 180ppm to 360ppm. That would be +8°C from the first 2XCO2.
As I have discussed, in the paper “Climate effects of aerosols reduce economic inequality. Nature Climate Change, 2020; DOI: 10.1038/s41558–020–0699-y” the authors find that:
Estimates indicate that aerosol pollution emitted by humans is offsetting about 0.7 degrees Celsius, or about 1.3 degrees Fahrenheit, of the warming due to greenhouse gas emissions,” said lead author Zheng. “This translates to a 40-year delay in the effects of climate change.”
“Without cooling caused by aerosol emissions, we would have achieved 2010-level global mean temperatures in 1970.”
Which, if this is at all correct. Could have meant that +0.7°C of warming was being “masked” by aerosol sulfate particulates in the 70's. The result of burning high sulfur fossil fuels.
In which case the actual temperature in the 70’s would have been about +1.3°C at 330ppm and +2°C over our 1850 baseline at 360ppm doesn't seem implausible at all. Particularly given the fights we have had in calibrating our “zero” point on the CO2ppm to +°C scale.
This narrative simplifies our understanding of the Climate System and brings an overall order to all the lines of evidence.
In this understanding of the Climate System we “pushed” the system out of the “First 2XCO2 State” by pushing CO2 levels up above 360ppm. At that point we had raised the Global Mean Temperature about +2°C over the 1850 baseline.
At that temperature in the paleoclimate record there is NO permafrost. Something we didn’t know in the 1970’s. So, in effect we began the “Second 2XCO2 State” by melting the permafrost for the first time in 750,000 years.
The Second 2XCO2 doubling is from 360ppm to 720ppm and will increase temperatures +8°C to about +10°C over our 1850 baseline. That indicates warming of about +5°C to +6°C over our 1850 baseline at 540ppm.
Which is consistent with your findings of +4.5°C to +5.5°C for 2XCO2 over the 1850 280ppm CO2 level.
This narrative also neatly explains the PETM fossil evidence by making enough warming possible to account for alligators and palm trees living around the Arctic Ocean at CO2 levels of only around 2800ppm. Which is in accord with the paleoclimate estimate for CO2 levels at that time.
The idea that more CO2 brings a steeper degree of warming appears to be wrong based on the notion of saturation where we should see a reduction in the effect of CO2 not an increase in its effect... can you explain?
I am happy to have you here on Substack, welcome! Four years ago I decided to write about climate change feeling a need to understand it better and a responsibility to share what I learned. I am no scientist, but a good communicator and able to wade through the reports experts such as you create. I am a believer in degrowth, but realize that concept should have been promoted 50 years ago. Like you, I firmly believe 1.5° was dead a while ago, and am certain major tipping points have been exceeded such as the Arctic.
Given that the Amazon is likely lost, too I investigated SAI/SRM about a year ago to form an opinion of its use analyzing its potential cooling effects, and the myriad questions it raises. It felt like an inevitable Hail Mary to me until the latest administration of science deniers was installed. Now, who knows? Here is a link to the article if you have time. What is your opinion of this radical action? Potentially effective? Or a low odds gamble?
I am not so pessimistic. Those are topics we will get into in due course. There needs first to be recognition of the implications of high climate sensitivity, the doubling of Earth's energy imbalance, and climate forcing in the pipeline. If we don't go step by step, the discussion seems to become stormy and descend into cognitive dissonance and chaos.
I am glad your pessimism is less than mine, and appreciate your desire to go step by step. A case built on logic and facts in a certain order would be ideal. Unfortunately, most humans don't operate with the same rational rigor of good scientists, and we have a real time factor. I deeply believe the core of our problem is behavioral, and that appealing to people with facts AND emotion is important. Few have the time to digest the science in a deep way, and it's not presented in the media front and center as it should be.
Always appreciate Jim’s radical objectivity, in a world where everything must be labeled “good” or “bad.” For example, is burning bunker fuel on ships “good” or “bad?” The answer is that it pollutes the air locally but cools the climate globally. It’s up to policymakers to find ethical and creative ways to do what’s best for everyone.
James Hansen, would you care to comment on the William. A. van Wijngaarden and William Happer 2019 paper on the radiative transfer process titled: Infrared Forcing by Greenhouse Gases. Happer writes "The point of the paper is that the direct effects of greenhouse gases on the thermal radiation to space is much smaller than the average person realizes. This is the radiation that gets rid of solar heating. A 100% increase of CO2 (doubling) only reduces radiation to space by 1%."
They reviewed how the atmospheric temperatures and the concentrations of Earth’s five most important, naturally occurring greenhouse gases, H2O, CO2, O3, N2O and CH4 control the cloud-free, thermal radiative fluxes from the Earth to outer space.
The main concern of the paper is radiative transfer through an atmosphere consisting of different layers, with different temperatures and different densities of the five most important greenhouse gases. The greenhouse gases studied have very rich spectra in the infrared region. Via the very extensive HITRAN database the frequencies and intensities of transitions are available. More than 300 000 transitions have been employed. From these observation-based intensities electric dipole transition matrix elements were derived, and hence experimental molecular infrared cross sections were obtained. From the warm surface of the Earth, infrared radiation is emitted and eventually absorbed and transferred in the form of heat and infrared radiation to the upper layers of the atmosphere. From there this heat is lost to outer space via infrared radiation. The question is to what extent higher concentrations of greenhouse gases affect this process?
The answer of Van Wijngaarden and Happer is clear. Doubling the CO2 concentration increases the infrared absorption by only a few percent. The reason is that extensive saturation takes place. In simple terms, if the available CO2 already absorbs almost all of the infrared energy, adding more will make little difference.
HI Natasha, I look from the perspective that we are changing the climate sensitivity through land use changes and nutrient flow changes. Rob de laet came to the same conclusion when he did a study of the effects of Amazon deforestation and latent heat transfer
I used AI to look into cloud changes and solar radiation balance with a focus on the loss of CCN and ICN from deforestation as I was interested in their ability especially ICN to transfer very low temperature upper atmosphere air down through a cumulonimbus cloud spire and their overall ability to create the height and density of this latent heat transfer, this is what I could ascertain
Deforestation is replacing high‐albedo anvil tops with smaller, warmer‐topped cells yields:
Shifts from fewer large towers to more numerous small cells reduce the total area of cold, bright anvils. and hance less OLR release into lower density upper atmosphere and hence into space
Smaller convective cells release comparable fractions of their latent heat to space but in much smaller quantities. Their reduced anvil‐top area and warmer cloud tops mean that, per storm, both shortwave reflection and outgoing longwave emission fall off sharply compared to large cumulonimbus spires. The rate of change was of +0.2w m2 for every 10% change I focused on the tropical region as temperate forest tend to have lower flatter cloud masses with less of an effect.
Global Trend from Large to Small Deep Convective Systems
Across the tropics and subtropics, long‐term satellite analyses reveal a consistent reorganization of storm sizes:
Large deep‐convective systems (DCS, horizontal scale > 100 km) have declined by about 8 ± 3 % per decade.
Small convective cells (scale < 30 km) have increased by about 10 ± 4 % per decade.
These figures average results from eight major tropical basins (e.g., Africa, Americas, Asia–Pacific) over the period 1980–2020.
Regional Variations, Basin
Large DCS Trend (% per decade)
Small Cell Trend (% per decade)
Tropical Africa & Atlantic
–12 ± 4
+15 ± 5
Tropical Americas (GOES)
– 7 ± 2
+ 9 ± 3
Asia–Pacific (MTSAT)
– 6 ± 3
+11 ± 4
Mean over all basins
– 8 ± 3
+10 ± 4
While the direction of change is uniform—large storms breaking into many smaller, longer‐lived cells—the magnitude of the shift is strongest over Africa land which is the high end at -12 and +15 almost double all the rest.
Unfortunately being AI this needs to be checked so I did not include it in the article ,but it shows a trend .
Two other points of interest are the changes in diurnal cloud especially in regards to nutrient availability over oceans and the nutrient recycling ability water offers to an environment which kicks off the all important bioaerosols.
James Hansen, Thank you for writing here on Substack. Would you care comment on the August 2024 paper by Ned Nikolov and Karl Zeller some suggesting it's a paradigm shifting work, published by peer reviewed journal MDPI Geomatics. Their analysis claims to reveal that the observed decrease of planetary albedo along with reported variations of the Total Solar Irradiance (TSI) explain 100% of the global warming trend and 83% of the GSAT interannual variability as documented by six satellite- and ground-based monitoring systems over the past 24 years. Changes in Earth’s cloud albedo emerged as the dominant driver of GSAT, while TSI only played a marginal role. The new climate sensitivity model also helped them analyze the physical nature of the Earth’s Energy Imbalance (EEI) calculated as a difference between absorbed shortwave and outgoing longwave radiation at the top of the atmosphere. Observations and model calculations revealed that EEI results from a quasi-adiabatic attenuation of surface energy fluxes travelling through a field of decreasing air pressure with altitude. In other words, the adiabatic dissipation of thermal kinetic energy in ascending air parcels gives rise to an apparent EEI, which does not represent “heat trapping” by increasing atmospheric greenhouse gases as currently assumed. We provide numerical evidence that the observed EEI has been misinterpreted as a source of energy gain by the Earth system on multidecadal time scales.
Your job has just become even more difficult with the Republican and international Conservative forces are doing their utmost to destroy all the understanding that climate research has discovered and putting the world we know, or better knew, at extreme risk . All for ideological and short term financial considerations.
I am so happy to see you here on Substack. Thank you Richard Crim for the alert. Everyone here concerned about our too rapidly changing climate welcomed your strong presence.
Understand the ECS (I assume not ESS) estimator at +4.5degC. And the variability/uncertainty around such an estimate. Let us take it at the 4.5 figure.
The question/issue for me becomes: what is the range of expected weather outcomes anticipated at +4.5degC in different locations. What range of local temperatures might be experienced. What strength of Cyclones? (Compared to current experience). Of course I realise it will be worse! Are there good sources of information?
After years of working on these issues, from ozone hole to marine pollution , CO2 debates and ecological worries: all the usual issues of the poly-crisis, plus actions, demos, writing, and testifying to government officials...as my focus shifted to what increasingly strikes me as a factor that links them all, and is a stunning threat to humans...the suddenly-discovered presence of nanoplastics in all of us.
A baby science, with years of research ahead, but one which is going to - if anything can - finally tackle governments and industries and hopefully, possibly, limit their powers of destruction.
Which is why my colleagues and I have have started a new substack:
The DoE report you mentioned contains an interesting foreword by the current Secretary of the department, Christopher Wright, who was given this position by climate denier Donald Trump. Wright describes himself here as an "energy entrepreneur." According to Wikipedia, "Before his appointment, he was the CEO of Liberty Energy, North America's second largest hydraulic fracturing company". This post was given to him as part of Trump's promise to Big Oil to support them. "Drill baby, drill" remember?
In his foreword, Wright says "The rise of human flourishing over the past two centuries is a story worth celebrating. Yet we are told—relentlessly—that the very energy systems that enabled this progress now pose an existential threat. Hydrocarbon-based fuels, the argument goes, must be rapidly abandoned or else we risk planetary ruin. That view demands scrutiny. That’s why I commissioned this report".
You are old enough to remember the Columbo TV series: what do you think Columbo would say had he come across this new "research" by the Department of Energy (!) under a businessman who got this job from the Billionaire's Club and who has a clear conflict of interest here?
Nigel, do you really think that it is appropriate to introduce politically motivated "science" from proud climate deniers here? Seriously: What on Earth are you thinking?
It would be one thing if you found research from legitimate sources that seemed to cast doubt on mainstream climate reporting. In fact, this paper by Dr Hansen is precisely an example of that, even though it does not turn the entire discussion upside down, as does the nonsense coming from climate deniers. There is a reason why the research by people actually qualified to carry it out, done independently around the world, has tended to fall into relatively solid agreement across the board, despite providing alternative views on many of the finer points. It is what one would expect from the disciplined fields of study behind this variety of work.
Your response is highly predictable, but even after many years responding to posts and comments it’s still a disappointment as that certain truth killing bias comes through in your writing.
I must correct you on some points....
The 1st thing I would like you to do is address people correctly and respectfully if you want a balanced discussion… There are many of us (and a growing number) who don’t deny the climate is changing but are “skeptics” that it is an emergency or that it requires any form of mitigation and our view is that we just need some localized adaption. Another term we use is climate “realists” not alarmists, but certainty “denial” associated with the word climate does not work.
The 2nd thing the climate alarmists always do is declare that we are unqualified to mess with the frozen climate narrative as we are pathologically biased due to our background or current roles or allegiances etc. …. On this basis looking at your current role its very clear you are well beyond messing with in any logical manner to seek the truth.
The 3rd thing they do is arrogantly declare that only “legitimate sources” can be used to frame the truth even when it has been proven how much political subjugation by the UN and others (example…the hockey stick) has been used to put the climate science horse way behind the political policy cart with any scientific truth over-ran with this cart using words like “the science is settled” and “a firm consensus exists” to freeze the dangerous narrative..
Let’s be clear…
President Trump and his administration don’t have to request such a report or gather feedback from its publication and review. They have already set policy to reverse the stupidity of NetZero undertaken by the prior administration…., as it’s clear that NetZero is unnecessary, technologically unattainable, economically unviable and extremely foolish.
The report is a mature attempt to get to reality on a very unsettled science and reverse the dangerous frozen narrative and save the politically subjugated science community from itself.
I will be surprised if Hansen responds to the posts….. most of these guys don’t want to debate the truth and keep falling back on the rhetoric I have just described.
Well guess what… Colombo would declare that it is no crime to seek the truth.
And we realists are getting listened too far more going forward than you will be.. 😊
PS…The big issues the report gets right..... climate change is mild.. impacts are small and mostly benign, and the crazy predictions using models don’t work….. and maybe CO2 is not the main driver… looks good to me.
One of the DoE report authors makes the position clear.
‘Grossly exaggerated’: Media gives ‘little attention’ to new bombshell climate report
I am unable to reply adequately here, as the character limit is unreasonably low. I will just say that there is a difference between honestly trying to find out the truth and a solution, and to looking for a substitute because the truth and its solution is too uncomfortable for you and for your world view. People need to realize it's not themselves who have caused this, it's all our so-called heroes. But some people just can't deal with reality when it cuts too close.
Again…… its very clear you find it hard not to tether your argument to your own frozen view of the truth and solution, and perhaps you had been looking in the mirror when you blame others for not facing reality.. … This is a huge shame.
By the way, regarding your request for Hansen to look at the DoE propaganda, the sad state of the US now under Trump is that if he publicly gave his real opinion of it he could lose his job, even if he were polite about it. So in addition to it being so obviously nonsense and a waste of time, there's that.
You seemed to think I was being rude earlier. I don't agree. Calling someone who thinks climate change is real but that the impacts are, as you say, "mild" and "small" is a fitting label for someone who denies the basic findings of scientific research conducted my thousands of totally unrelated individuals in countries all over the world. Who is holding them all together in this big lie, Nigel? Really.
Well…Thank you….. in a separate comment you just gave yourself the correct answer to your other tired question which is..…
“Why wont we “deniers” accept the basic findings of scientific research conducted my thousands of totally unrelated individuals in countries all over the world.”
You said…..“By the way, regarding your request for Hansen to look at the DoE propaganda, the sad state of the US now under Trump is that if he publicly gave his real opinion of it he could lose his job, even if he were polite about it.”
Well…. ain’t that the truth…. Because until very recently this has been the exact predicament of many scientists worldwide also trapped in the narrative binding and political subjugation of peer review, publication, funding, and job security entrapment of the frozen narrative of the UN.
Also… when any one with a technical capability reviews the data its clear that you can drive a bus through the climate science as at best its unsettled as per the comments of the DoE report.
I am connected with many scientists that agree with my position.. wake up matey.. “times are a changing” as they say.
James Hansen, in your 'Forest Trees' paper, you write: "Even the CO2 increase during the iconic PETM (Paleocene Eocene Thermal Maximum) event was an order of magnitude slower than the human-made change."
The PETM occurred around 55.8 million years ago (Ma) and lasted about 200 thousand years (Ka).
But geological data sets going back 55.8 million years ago would have to have resolution ratios of 1 : ~0.0000018 to see the same accelerations during our +- 50 years or so of modern industrial CO2 emissions.
How is it possible to see such fine temporal resolution in geological data 55.8 million years ago?
Great article however I have a question.
You are calculating 2XCO2 as resulting in +4.5°C to +5.5°C of warming. Which seems bad enough.
Are you aware of the recent paleoclimate analysis that indicates warming is approximately +8°C for each doubling of CO2?
CR94 - It’s looking like each "CO2 Doubling” causes +8°C of warming. The 1st doubling was +180ppm to +360ppm. That takes us to +2°C. The NEXT doubling to +720ppm takes us to +10°C. Hansen puts us at +520ppm(e) right now.
A 485-million-year history of Earth’s surface temperature - Science, 20 Sep 2024, Vol 385, Issue 6715, DOI: 10.1126/science.adk3705
Judd et al. present a record of GMST over the past 485 million years that they constructed by combining proxy data with climate modeling (see the Perspective by Mills). They found that GMST varied over a range from 11° to 36°C, with an “apparent” climate sensitivity of ∼8°C, about two to three times what it is today.
The GMST-CO2 relationship indicates a notably constant “apparent” Earth system sensitivity (i.e., the temperature response to a doubling of CO2, including fast and slow feedbacks) of ∼8°C, with no detectable dependence on whether the climate is warm or cold.
I postulate that since 180ppm CO2 seems to be "rock bottom" for CO2 levels over the last 485my it should be used as our "starting baseline" rather than the arbitrary 280ppm present in 1850.
This results in the following:
The “first” 2XCO2 is 180ppm to 360ppm. That would be +8°C from the first 2XCO2.
As I have discussed, in the paper “Climate effects of aerosols reduce economic inequality. Nature Climate Change, 2020; DOI: 10.1038/s41558–020–0699-y” the authors find that:
Estimates indicate that aerosol pollution emitted by humans is offsetting about 0.7 degrees Celsius, or about 1.3 degrees Fahrenheit, of the warming due to greenhouse gas emissions,” said lead author Zheng. “This translates to a 40-year delay in the effects of climate change.”
“Without cooling caused by aerosol emissions, we would have achieved 2010-level global mean temperatures in 1970.”
Which, if this is at all correct. Could have meant that +0.7°C of warming was being “masked” by aerosol sulfate particulates in the 70's. The result of burning high sulfur fossil fuels.
In which case the actual temperature in the 70’s would have been about +1.3°C at 330ppm and +2°C over our 1850 baseline at 360ppm doesn't seem implausible at all. Particularly given the fights we have had in calibrating our “zero” point on the CO2ppm to +°C scale.
This narrative simplifies our understanding of the Climate System and brings an overall order to all the lines of evidence.
In this understanding of the Climate System we “pushed” the system out of the “First 2XCO2 State” by pushing CO2 levels up above 360ppm. At that point we had raised the Global Mean Temperature about +2°C over the 1850 baseline.
At that temperature in the paleoclimate record there is NO permafrost. Something we didn’t know in the 1970’s. So, in effect we began the “Second 2XCO2 State” by melting the permafrost for the first time in 750,000 years.
The Second 2XCO2 doubling is from 360ppm to 720ppm and will increase temperatures +8°C to about +10°C over our 1850 baseline. That indicates warming of about +5°C to +6°C over our 1850 baseline at 540ppm.
Which is consistent with your findings of +4.5°C to +5.5°C for 2XCO2 over the 1850 280ppm CO2 level.
This narrative also neatly explains the PETM fossil evidence by making enough warming possible to account for alligators and palm trees living around the Arctic Ocean at CO2 levels of only around 2800ppm. Which is in accord with the paleoclimate estimate for CO2 levels at that time.
Thoughts?
The idea that more CO2 brings a steeper degree of warming appears to be wrong based on the notion of saturation where we should see a reduction in the effect of CO2 not an increase in its effect... can you explain?
Ice Age was 6K colder (not 3K)
climate forcing 4 W/m² for 2×CO2.
response to this climate forcing 4 W/m², including slow feedbacks, is 10K
https://www.columbia.edu/~jeh1/mailings/2022/Pipeline.arXiv.13December2022.pdf
I am happy to have you here on Substack, welcome! Four years ago I decided to write about climate change feeling a need to understand it better and a responsibility to share what I learned. I am no scientist, but a good communicator and able to wade through the reports experts such as you create. I am a believer in degrowth, but realize that concept should have been promoted 50 years ago. Like you, I firmly believe 1.5° was dead a while ago, and am certain major tipping points have been exceeded such as the Arctic.
I wrote about Arctic permafrost here:
https://geoffreydeihl.substack.com/p/permafrost-maybe-not
Given that the Amazon is likely lost, too I investigated SAI/SRM about a year ago to form an opinion of its use analyzing its potential cooling effects, and the myriad questions it raises. It felt like an inevitable Hail Mary to me until the latest administration of science deniers was installed. Now, who knows? Here is a link to the article if you have time. What is your opinion of this radical action? Potentially effective? Or a low odds gamble?
https://geoffreydeihl.substack.com/p/stratospheric-aerosol-injection-earths
I am not so pessimistic. Those are topics we will get into in due course. There needs first to be recognition of the implications of high climate sensitivity, the doubling of Earth's energy imbalance, and climate forcing in the pipeline. If we don't go step by step, the discussion seems to become stormy and descend into cognitive dissonance and chaos.
I am glad your pessimism is less than mine, and appreciate your desire to go step by step. A case built on logic and facts in a certain order would be ideal. Unfortunately, most humans don't operate with the same rational rigor of good scientists, and we have a real time factor. I deeply believe the core of our problem is behavioral, and that appealing to people with facts AND emotion is important. Few have the time to digest the science in a deep way, and it's not presented in the media front and center as it should be.
I'm looking forward to reading more from you.
Always appreciate Jim’s radical objectivity, in a world where everything must be labeled “good” or “bad.” For example, is burning bunker fuel on ships “good” or “bad?” The answer is that it pollutes the air locally but cools the climate globally. It’s up to policymakers to find ethical and creative ways to do what’s best for everyone.
Now, about those “policymakers”
. . .
James Hansen, would you care to comment on the William. A. van Wijngaarden and William Happer 2019 paper on the radiative transfer process titled: Infrared Forcing by Greenhouse Gases. Happer writes "The point of the paper is that the direct effects of greenhouse gases on the thermal radiation to space is much smaller than the average person realizes. This is the radiation that gets rid of solar heating. A 100% increase of CO2 (doubling) only reduces radiation to space by 1%."
They reviewed how the atmospheric temperatures and the concentrations of Earth’s five most important, naturally occurring greenhouse gases, H2O, CO2, O3, N2O and CH4 control the cloud-free, thermal radiative fluxes from the Earth to outer space.
The main concern of the paper is radiative transfer through an atmosphere consisting of different layers, with different temperatures and different densities of the five most important greenhouse gases. The greenhouse gases studied have very rich spectra in the infrared region. Via the very extensive HITRAN database the frequencies and intensities of transitions are available. More than 300 000 transitions have been employed. From these observation-based intensities electric dipole transition matrix elements were derived, and hence experimental molecular infrared cross sections were obtained. From the warm surface of the Earth, infrared radiation is emitted and eventually absorbed and transferred in the form of heat and infrared radiation to the upper layers of the atmosphere. From there this heat is lost to outer space via infrared radiation. The question is to what extent higher concentrations of greenhouse gases affect this process?
The answer of Van Wijngaarden and Happer is clear. Doubling the CO2 concentration increases the infrared absorption by only a few percent. The reason is that extensive saturation takes place. In simple terms, if the available CO2 already absorbs almost all of the infrared energy, adding more will make little difference.
https://co2coalition.org/wp-content/uploads/2022/03/Infrared-Forcing-by-Greenhouse-Gases-2019-Revised-3-7-2022.pdf.
https://co2coalition.org/publications/van-wijngaarden-and-happer-radiative-transfer-paper-for-five-greenhouse-gases-explained/
https://arxiv.org/abs/2006.03098v1
https://earthscience.stackexchange.com/questions/25227/what-is-technically-wrong-with-wijngaarden-happers-paper-claiming-to-show-tha
HI Natasha, I look from the perspective that we are changing the climate sensitivity through land use changes and nutrient flow changes. Rob de laet came to the same conclusion when he did a study of the effects of Amazon deforestation and latent heat transfer
https://medcraveonline.com/IJBSBE/IJBSBE-09-00237.pdf
in an article I co wrote https://substack.com/@tcrethers/p-168947916
I used AI to look into cloud changes and solar radiation balance with a focus on the loss of CCN and ICN from deforestation as I was interested in their ability especially ICN to transfer very low temperature upper atmosphere air down through a cumulonimbus cloud spire and their overall ability to create the height and density of this latent heat transfer, this is what I could ascertain
Deforestation is replacing high‐albedo anvil tops with smaller, warmer‐topped cells yields:
Shifts from fewer large towers to more numerous small cells reduce the total area of cold, bright anvils. and hance less OLR release into lower density upper atmosphere and hence into space
Smaller convective cells release comparable fractions of their latent heat to space but in much smaller quantities. Their reduced anvil‐top area and warmer cloud tops mean that, per storm, both shortwave reflection and outgoing longwave emission fall off sharply compared to large cumulonimbus spires. The rate of change was of +0.2w m2 for every 10% change I focused on the tropical region as temperate forest tend to have lower flatter cloud masses with less of an effect.
Global Trend from Large to Small Deep Convective Systems
Across the tropics and subtropics, long‐term satellite analyses reveal a consistent reorganization of storm sizes:
Large deep‐convective systems (DCS, horizontal scale > 100 km) have declined by about 8 ± 3 % per decade.
Small convective cells (scale < 30 km) have increased by about 10 ± 4 % per decade.
These figures average results from eight major tropical basins (e.g., Africa, Americas, Asia–Pacific) over the period 1980–2020.
Regional Variations, Basin
Large DCS Trend (% per decade)
Small Cell Trend (% per decade)
Tropical Africa & Atlantic
–12 ± 4
+15 ± 5
Tropical Americas (GOES)
– 7 ± 2
+ 9 ± 3
Asia–Pacific (MTSAT)
– 6 ± 3
+11 ± 4
Mean over all basins
– 8 ± 3
+10 ± 4
While the direction of change is uniform—large storms breaking into many smaller, longer‐lived cells—the magnitude of the shift is strongest over Africa land which is the high end at -12 and +15 almost double all the rest.
Unfortunately being AI this needs to be checked so I did not include it in the article ,but it shows a trend .
Two other points of interest are the changes in diurnal cloud especially in regards to nutrient availability over oceans and the nutrient recycling ability water offers to an environment which kicks off the all important bioaerosols.
James Hansen, Thank you for writing here on Substack. Would you care comment on the August 2024 paper by Ned Nikolov and Karl Zeller some suggesting it's a paradigm shifting work, published by peer reviewed journal MDPI Geomatics. Their analysis claims to reveal that the observed decrease of planetary albedo along with reported variations of the Total Solar Irradiance (TSI) explain 100% of the global warming trend and 83% of the GSAT interannual variability as documented by six satellite- and ground-based monitoring systems over the past 24 years. Changes in Earth’s cloud albedo emerged as the dominant driver of GSAT, while TSI only played a marginal role. The new climate sensitivity model also helped them analyze the physical nature of the Earth’s Energy Imbalance (EEI) calculated as a difference between absorbed shortwave and outgoing longwave radiation at the top of the atmosphere. Observations and model calculations revealed that EEI results from a quasi-adiabatic attenuation of surface energy fluxes travelling through a field of decreasing air pressure with altitude. In other words, the adiabatic dissipation of thermal kinetic energy in ascending air parcels gives rise to an apparent EEI, which does not represent “heat trapping” by increasing atmospheric greenhouse gases as currently assumed. We provide numerical evidence that the observed EEI has been misinterpreted as a source of energy gain by the Earth system on multidecadal time scales.
https://www.mdpi.com/2673-7418/4/3/17
And the IPCC still appears to be underestimating the effects of CH4 vented from melting tundra, ocean clathrates, tropical swamps and forest fire...
Your job has just become even more difficult with the Republican and international Conservative forces are doing their utmost to destroy all the understanding that climate research has discovered and putting the world we know, or better knew, at extreme risk . All for ideological and short term financial considerations.
I am so happy to see you here on Substack. Thank you Richard Crim for the alert. Everyone here concerned about our too rapidly changing climate welcomed your strong presence.
Thank you Dr Hansen, et al!
Understand the ECS (I assume not ESS) estimator at +4.5degC. And the variability/uncertainty around such an estimate. Let us take it at the 4.5 figure.
The question/issue for me becomes: what is the range of expected weather outcomes anticipated at +4.5degC in different locations. What range of local temperatures might be experienced. What strength of Cyclones? (Compared to current experience). Of course I realise it will be worse! Are there good sources of information?
Great you won't let up. We need you.
After years of working on these issues, from ozone hole to marine pollution , CO2 debates and ecological worries: all the usual issues of the poly-crisis, plus actions, demos, writing, and testifying to government officials...as my focus shifted to what increasingly strikes me as a factor that links them all, and is a stunning threat to humans...the suddenly-discovered presence of nanoplastics in all of us.
A baby science, with years of research ahead, but one which is going to - if anything can - finally tackle governments and industries and hopefully, possibly, limit their powers of destruction.
Which is why my colleagues and I have have started a new substack:
https://ournewrealitytheplasticene.substack.com/p/our-new-reality-1e9
CO2 cannot warm the atmosphere. Why? It absorbs and re-emits extremely weak long wave IR energy in an atmosphere that is already warmer.
Not only is the energy transfer vanishingly small, so is CO2, at 400 ppm.
The Second Law of Thermodynamics states that heat moves from hot to cold, so CO2 cannot warm things warmer than it.
What do you think about the DoE report?: https://nigelsouthway.substack.com/p/new-climate-report-from-the-us-doe
The DoE report you mentioned contains an interesting foreword by the current Secretary of the department, Christopher Wright, who was given this position by climate denier Donald Trump. Wright describes himself here as an "energy entrepreneur." According to Wikipedia, "Before his appointment, he was the CEO of Liberty Energy, North America's second largest hydraulic fracturing company". This post was given to him as part of Trump's promise to Big Oil to support them. "Drill baby, drill" remember?
In his foreword, Wright says "The rise of human flourishing over the past two centuries is a story worth celebrating. Yet we are told—relentlessly—that the very energy systems that enabled this progress now pose an existential threat. Hydrocarbon-based fuels, the argument goes, must be rapidly abandoned or else we risk planetary ruin. That view demands scrutiny. That’s why I commissioned this report".
You are old enough to remember the Columbo TV series: what do you think Columbo would say had he come across this new "research" by the Department of Energy (!) under a businessman who got this job from the Billionaire's Club and who has a clear conflict of interest here?
Nigel, do you really think that it is appropriate to introduce politically motivated "science" from proud climate deniers here? Seriously: What on Earth are you thinking?
It would be one thing if you found research from legitimate sources that seemed to cast doubt on mainstream climate reporting. In fact, this paper by Dr Hansen is precisely an example of that, even though it does not turn the entire discussion upside down, as does the nonsense coming from climate deniers. There is a reason why the research by people actually qualified to carry it out, done independently around the world, has tended to fall into relatively solid agreement across the board, despite providing alternative views on many of the finer points. It is what one would expect from the disciplined fields of study behind this variety of work.
Mark
Your response is highly predictable, but even after many years responding to posts and comments it’s still a disappointment as that certain truth killing bias comes through in your writing.
I must correct you on some points....
The 1st thing I would like you to do is address people correctly and respectfully if you want a balanced discussion… There are many of us (and a growing number) who don’t deny the climate is changing but are “skeptics” that it is an emergency or that it requires any form of mitigation and our view is that we just need some localized adaption. Another term we use is climate “realists” not alarmists, but certainty “denial” associated with the word climate does not work.
The 2nd thing the climate alarmists always do is declare that we are unqualified to mess with the frozen climate narrative as we are pathologically biased due to our background or current roles or allegiances etc. …. On this basis looking at your current role its very clear you are well beyond messing with in any logical manner to seek the truth.
The 3rd thing they do is arrogantly declare that only “legitimate sources” can be used to frame the truth even when it has been proven how much political subjugation by the UN and others (example…the hockey stick) has been used to put the climate science horse way behind the political policy cart with any scientific truth over-ran with this cart using words like “the science is settled” and “a firm consensus exists” to freeze the dangerous narrative..
Let’s be clear…
President Trump and his administration don’t have to request such a report or gather feedback from its publication and review. They have already set policy to reverse the stupidity of NetZero undertaken by the prior administration…., as it’s clear that NetZero is unnecessary, technologically unattainable, economically unviable and extremely foolish.
The report is a mature attempt to get to reality on a very unsettled science and reverse the dangerous frozen narrative and save the politically subjugated science community from itself.
I will be surprised if Hansen responds to the posts….. most of these guys don’t want to debate the truth and keep falling back on the rhetoric I have just described.
Well guess what… Colombo would declare that it is no crime to seek the truth.
And we realists are getting listened too far more going forward than you will be.. 😊
PS…The big issues the report gets right..... climate change is mild.. impacts are small and mostly benign, and the crazy predictions using models don’t work….. and maybe CO2 is not the main driver… looks good to me.
One of the DoE report authors makes the position clear.
‘Grossly exaggerated’: Media gives ‘little attention’ to new bombshell climate report
https://www.youtube.com/watch?v=LckkSXkr4Nk
Hi Nigel,
I am unable to reply adequately here, as the character limit is unreasonably low. I will just say that there is a difference between honestly trying to find out the truth and a solution, and to looking for a substitute because the truth and its solution is too uncomfortable for you and for your world view. People need to realize it's not themselves who have caused this, it's all our so-called heroes. But some people just can't deal with reality when it cuts too close.
Again…… its very clear you find it hard not to tether your argument to your own frozen view of the truth and solution, and perhaps you had been looking in the mirror when you blame others for not facing reality.. … This is a huge shame.
By the way, regarding your request for Hansen to look at the DoE propaganda, the sad state of the US now under Trump is that if he publicly gave his real opinion of it he could lose his job, even if he were polite about it. So in addition to it being so obviously nonsense and a waste of time, there's that.
You seemed to think I was being rude earlier. I don't agree. Calling someone who thinks climate change is real but that the impacts are, as you say, "mild" and "small" is a fitting label for someone who denies the basic findings of scientific research conducted my thousands of totally unrelated individuals in countries all over the world. Who is holding them all together in this big lie, Nigel? Really.
Well…Thank you….. in a separate comment you just gave yourself the correct answer to your other tired question which is..…
“Why wont we “deniers” accept the basic findings of scientific research conducted my thousands of totally unrelated individuals in countries all over the world.”
You said…..“By the way, regarding your request for Hansen to look at the DoE propaganda, the sad state of the US now under Trump is that if he publicly gave his real opinion of it he could lose his job, even if he were polite about it.”
Well…. ain’t that the truth…. Because until very recently this has been the exact predicament of many scientists worldwide also trapped in the narrative binding and political subjugation of peer review, publication, funding, and job security entrapment of the frozen narrative of the UN.
Also… when any one with a technical capability reviews the data its clear that you can drive a bus through the climate science as at best its unsettled as per the comments of the DoE report.
I am connected with many scientists that agree with my position.. wake up matey.. “times are a changing” as they say.
James Hansen, in your 'Forest Trees' paper, you write: "Even the CO2 increase during the iconic PETM (Paleocene Eocene Thermal Maximum) event was an order of magnitude slower than the human-made change."
The PETM occurred around 55.8 million years ago (Ma) and lasted about 200 thousand years (Ka).
But geological data sets going back 55.8 million years ago would have to have resolution ratios of 1 : ~0.0000018 to see the same accelerations during our +- 50 years or so of modern industrial CO2 emissions.
How is it possible to see such fine temporal resolution in geological data 55.8 million years ago?