By David Wojick |October 20th, 2020|Climate
Climate science is dominated by alarmists addicted to the idea that increasing carbon dioxide will cause dangerous global warming. How much warming is thus the central scientific question.
This question has been surprisingly difficult to answer despite 40 years of research, costing tens of billions of dollars. Now the issue is exploding because two different answers are emerging, one harmlessly low and the other dangerously high. This divergence is a crisis for the alarmist community. How they handle it remains to be seen.
What follows is a slightly technical explanation of the situation.
The issue centers on a benchmark estimate of the impact of increasing CO2 on global temperature. This is called the “equilibrium climate sensitivity” or ECS. The basic question is what will the global average temperature be when the CO2 level is double the supposedly original level of 280 ppm? That is, what will it be when we hit 560 ppm.
However, since it may take the climate system some time to adjust to this new high level, the question is what the temperature will be when the system equilibrates to this doubling, which may be some time after we hit 560. Also, this is about sensitivity, so ECS is not the new high temperature. It is the number of degrees C higher than the original temperature that this new high temperature will be.
So if the new high temperature is, say, 2.2 degrees C higher then ECS = 2.2 degrees.
Technically ECS is often an abstraction, something that only happens in climate models, but model ECS is taken as an important estimate of real ECS. In the models ECS is often estimated by simply doubling the CO2 instantaneously, whereas in reality this takes centuries.
All this said, I can now explain the emerging crisis.
For many decades the accepted model estimates of ECS have ranged from 1.5 to 4.5 degrees C. Different models give different values, but the acceptable range has not changed. That the range is so big has been a policy problem. Warming as little as 1.5 degrees might be harmless, while 4.5 might be dangerous. But the ECS range has been stubbornly persistent, refusing to narrow to a specific value.
Now, suddenly, there is a huge new problem. ECS has exploded! It is not that it is higher, or lower — it is both. Two new lines of research have diverged sharply on the estimated value of ECS.
The first line of research takes a new approach called observational ECS. The idea is that since the CO2 level is almost half way to doubling we should be able to derive ECS empirically from the observed relationship between CO2 increase and temperature increase.
There have been a number of observational studies and many are getting ECS values well below 1.5, which are harmless indeed. Values of 1.2 and 1.3 are common.
But at the same time there has been a new wave of modeling studies and these are getting ECS values way above 4.5, which would be truly dangerous. Here values of 5.2 and 5.3 are to be found.
Note that the modeling community is divided over accepting these new hot model numbers. After all, they imply that the modeling done over the last forty years or so has been wrong, including a lot of the recent modeling which is still within the old range.
The upshot of all this is that the science of ECS is in a shambles. Given that ECS addresses the core science of climate alarmism, this is truly a crisis. Has the modeling been wrong for 40 years? Is it wrong now? What about observation, which is supposed to rule in science? The scientific method says observation trumps theoretical modeling.
This is also a policy crisis. If we have no idea how sensitive the climate system will be to increasing CO2 levels then we have no basis for making climate change policy. If the observation values are right then there simply is no climate emergency.
How will this huge new uncertainty play out? Fortunately we will get at least a glimpse fairly soon. The latest IPCC assessment report (AR6) is presently under review and should be out in the next year or so. This report is supposed to review the state of climate change science, albeit from an alarmist point of view.
How the IPCC handles the exploding ECS range will be interesting to see, at the very least. They may choose to ignore it because it has to hurt alarmism. They may simply drop mention of the ECS altogether, it now being very inconvenient. But this glaring omission will be easy to call out.
Or they may only acknowledge the hot higher values, which favor alarmism. Here they risk making modeling look stupid (which it is). Plus this omission of critical evidence will also be easy to call out.
With the ECS range exploding the IPCC is caught between a hot rock and a cold hard place. So is alarmism. Stay tuned.
Author
David Wojick, Ph.D. is an independent analyst working at the intersection of science, technology and policy. For origins see
http://www.stemed.info/engineer_tackles_confusion.html
For over 100 prior articles for CFACT see
http://www.cfact.org/author/david-wojick-ph-d/
Available for confidential research and consulting.
Whether ECS is 1.0 or 6.0, the numbers are calculations, NOT measurements. There are NO measurements of how much CO2 warms the atmosphere. From the logarithmic chart posted on WUWT we know that the effect of CO2 by 400 ppm is very small.
The warmists claim that positive feedbacks will cause the warming, however again there is NO way to measure them. In fact, some scientists also suggest that the feedbacks from cloud and moisture could be negative. So i will not be surprised if we cool soon. The odds now are similar for either direction.
@Gerald Machnee:
I’m definitely in the Negative feedback camp, not as a scientist but as an engineer trained in the thermodynamics of water in the days of steam propulsion in our ships. Water does not comply with IPCC assumptions in that at evaporation the Planck Sensitivity Coefficient is Zero since it occurs at constant temperature. Further a quick look at the steam tables reveals that for every Kilogram of water evaporated some 694 Watthrs. of energy is pumped up into the atmosphere and beyond to space for dissipation before returning to earth. This done totally independently of CO2 levels. The IPCC appears to ignore this reality in concluding that the feedback is positive. A gross error in my opinion.
It’s likely on a water world that net feedbacks from a fourth, fifth or sixth molecule of plant food per 10,000 dry air molecules are negative. Thus ECS should be less than the non-feedback figure of 1.1 degree C per doubling.
Without knowing how much of whatever warming has occurred since AD 1850 is from natural forces, even observational ECS derivations can’t be considered accurate or precise, except to show that there’s nothing to worry about.
Most people who spread the positive feedback story do not know that it is an assumption, similarly to the Assumption that CO2 causes most warming.
News media are generally guilty of the CO2 assumption because they do not understand science, and are not willing to search for the truth.
In Canada all the media got sucked in by three of the political parties hijacking the last election by making the unfounded claim that we were in climate emergency instead of focusing on the national debt and deficit. We can see where that went now. Covid took over priority and the debt mushroomed.
Of course observational results have to remove other warming agents, such as nitrogen oxide from fertilizer, which is claimed to be 300 times stronger than CO2
The first line of research takes a new approach called observational ECS. The idea is that since the CO2 level is almost half way to doubling we should be able to derive ECS empirically from the observed relationship between CO2 increase and temperature increase.
There have been a number of observational studies and many are getting ECS values well below 1.5, which are harmless indeed. Values of 1.2 and 1.3 are common.
But at the same time there has been a new wave of modeling studies and these are getting ECS values way above 4.5, which would be truly dangerous. Here values of 5.2 and 5.3 are to be found.
I think those three paragraphs sum up the entire problem. If observation shows one number, how are any models showing 4-5 times that even vaguely justified?
“It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”
Before such a calculation you have to show that CO2 is the only thing causing warming.
If you assume it is, then the calculation gives a maximum possible, and real answer is substantially lower.
There is no real evidence that the ECS is anything but ZERO.
The real crisis is cyclical cooling of oceans, not warming and not warming pause. The race is on to cement and distort public policy before that becomes obvious. Biden is the Great White Hope.
More important is the contribution the rise in atmospheric carbon dioxide makes to global foodstuff production, without which famine would be far more widespread than it is. Alarmists studiously avoid any recognition that what they decry has significant benefits that far outweigh their overblown concerns.
The whole thing is totally useless. What kind of “observations” could you use to determine ECS? One could look at ice core data, which suggest huge deltas in temperature correlated with only moderate changes in CO2 concentrations. If 5K up or down go along with a delta of ~80ppm in CO2, then arguably a doubling of CO2 might mean some 15, or even 20K in ECS.
Now we know CO2 concentrations FOLLOWED temperatures, so there is nothing to take away from ice core data. You could only speculate if CO2 did enhance past climate change (serving as a feedback), but without any empiric evidence to support the claim.
The other possibility is to derive ECS from recent warming, which of course implies that warming was due to CO2. This however is largely a self fulfilling prophecy. The formula goes like: the warming is due to CO2, thus we can assess ECS, and with the ECS we explain the warming..
If we leave the box and look at the bigger picture, we easily find CO2 can not even cause significant warming, the ECS is only in the 0.1K range. But we have another far more important anthropogenic driver of climate, which are contrails. Then, all of a sudden, we have a valid explanation to why temperatures started climbing only in the 1970s. Then we also understand why Antartica has been exempt from warming, since there are no contrails.
The alarmists will not use the observations of how much the temperature has increased since CO2 was at 280.
We are now half way to the doubling figure of 560, so we should have had half the warming? Wrong! The CO2 forcing effect is logarithmic, so the strongest forcing has already happened. The final 140 ppm will have a significantly weaker forcing effect than the first 140.
They also know that the algorithm adjusted figures for the ‘warming’ rate that has actually taken place have been constantly adjusted, by warming the present but also cooling the past. This they cannot continue to do at anything like the rate they have done, it will eventually bring fairly recent figures into the ‘cooled’ ones making the already recorded statements about the ‘disastrous’ warming look ridiculous. ‘Hey, we have discovered it wasn’t that warm after all’ and make the model outputs and predictions look even more ridiculous than they already are.
The far sighted vocal alarmists should be toning down their rhetoric, unless they are so far gone they intend to go down with the sinking ship.
After much thought and adult beverages, , after I woke up, I came to the obvious conclusion that Griff is really a fictional commenter invented by the Moderator to stir up trafficat this here website. Yes, I dreamed that I overheard Mr. Moderator sitting on his “office” bar stool discussing what he was going to post next under the Griff moniker. His travelling “secretary”, sitting on the next bar stool, asked why he published fake Griff comments. Mr. Moderator responded that publishng a “Griff” comment was like throwing a few bananas in the monkey cage at the zoo, which gets all the monkeys excited, active and vocal. He apparently does that too. Being a Moderator is a stressful job, so we should all send him some “office supplies” (scotch, bourbon and MD 20/20 — 1968 vintage is his favorite). Keep those glorious, gripping, Griff comments coming, Mr. Moderator, we love them just like lions love raw meat.
Don’t know if you’re still reading comments, David, but ECS has no known physical meaning because the impact of CO2 emissions on the climate, if any, remains completely unknown.
The entire notion of ECS depends strictly on the predictive reliability of climate models. And climate models have no predictive reliability, at all.
All the extrapolations from CO2 radiation physics to the climate, starting with the Charney Report, follow from the fatal assumption of ceteris paribus. But the climate is not unchanging.
Fritz Möller had that figured out in 1964, and everyone since then has tendentiously ignored him.
Pat Frank
Good article at the first link.
I don’t believe the models deserve to be called climate models. A real climate model would need to be based on a detailed and correct knowledge of what causes climate change. Such a climate change physics model would be the foundation of a real global climate model … if that climate physics model existed.
So what we have, that are falsely called global climate models, are just computer games that have no predictive ability. They present the personal opinions of the owners. What they produce is not data. They predict whatever the owners want predicted. They consistently over predict global warming, showing a bias among the “owners”, because the errors are not random.
With any prototype “model”, the next iteration should make better predictions. But with the so called climate models, the global warming predictions remain consistemtly high, showing that accurate predictions are NOT a priority.
The “models” are so bad that the calculations could be done on the back of an envelope. Wild guess the TCS and the CO2 level growth rate and use a $5 calculator. Within one minute you’ll have your own wild guess of the global average temperature in the next 100 years. Make sure you present your “model” prediction with at least three decimal places, which is real science. As opposed to two or fewer decimal places, which is baloney, malarkey, banana earl (Brooklyn, USA)
and a steaming pile of farm animal digestive waste products.
Exactly right, Richard. Video-game science.
And thanks for the up-vote. 🙂
If you want to know what people really believe watch how they act. If someone thinks a ship is sinking they will get into a lifeboat. If they don’t believe the ship is sinking they will tell you why lifeboats are unsafe. The Warmists have consistently refused to get into the nuclear life boat. They know full well the ship isn’t sinking.
AGW is a conjecture based on only partial science and is full of holes. For example, the AGW conjecture depends upon the existence of a radiant greenhouse effect caused by trace gases in the Earth’s atmosphere with LWIR absorption bands. A real greenhouse does not stay warm because of so called greenhouse gases or because IR radiation is trapped inside the greenhouse. A real greenhouse stays warm because the glass limits cooling by convection. It is entirely a convective greenhouse effect that keeps a real greenhouse warm. So too on Earth where instead of glass, gravity and the heat capacity of the atmosphere limits cooling by convection. It is entirely a convective greenhouse effect that keeps the surface of the Earth on average 33 degrees C warmer than it would otherwise be. 33 degrees C is the amount of warming derived from first principals and 33 degrees C is what has been measured. Any additional warming caused by a radiant greenhouse effect has not been detected. If CO2 really affected climate one would expect that the increase in CO2 over the past 30 years would have caused at least a measurable increase in the dry lapse rate in the troposphere but that has not happened. A radiant greenhouse effect has not been detected in a real greenhouse, in the Earth’s atmosphere, or anywhere else in the solar system. The radiant greenhouse effect is hence science fiction so hence the AGW conjecture is science fiction as well.
But for those who still believe in the radiant greenhouse effect, initial calculations of the climate sensitivity came up with a nominal figure of 1.2 degrees C for a doubling of CO2 not including feedbacks. Christopher Monckton and associates and came up with the conclusion, based on measurements, that if all the warming since 1850 were caused by CO2 then the climate sensitivity of CO2 could not possible be more than 1.2 degrees C including feedbacks. A researcher from Japan pointed out that the original radiametric calculations forgot to include that fact that a doubling of CO2 will cause a slight decrease in the dry lapse rate in the troposphere which is a cooling effect that lowers the climate sensitivity of CO2 by more than a factor of 20, from 1.2 degrees C to less than .06 degrees C which is too small to measure. So no wonder that no one has been able to measure the climate sensitivity of CO2 because there is nothing to measure.
Then there is the issue of H2O feedback. The AGW conjecture assumption is that CO2 based warming causes more H2O to enter the atmosphere which causes more warming that causes even more H2O to enter the atmosphere and so forth. Not only is H2O a greenhouse gas but molecule per molecule H2O is a stronger IR absorber than is CO2 and on average there is roughly 50 times more H2O in the atmosphere. Compared to H2O the contribution of CO2 to the overall radiant greenhouse effect must be trivial. What the AGW conjecture ignores is that besides being the primary greenhouse gas, H2O is a primary coolant in the Earth’s atmosphere. The overall cooling effect of H2O is evidenced by the fact that the wet lapse rate is significantly less than the dry lapse rate which is a cooling effect. So instead of a potentially unstable positive feedback, H2O provides a negative climate stabilizing feedback. So instead of multiplying the climate sensitivity of CO2 by a nominal 3 we should divide the climate sensitivity of CO2 by 3 yielding a climate sensitivity of CO2 os less than .02 degrees C which is too small to measure and is effectively zero.
“The first line of research takes a new approach called observational ECS. The idea is that since the CO2 level is almost half way to doubling we should be able to derive ECS empirically from the observed relationship between CO2 increase and temperature increase.”
No. This line of reasoning assumes that CO2 exclusively controls the global temperature, directly and through feedbacks, with other factors merely resulting in minor self-correcting deviations. We know that this scenario is wrong. If it were correct, the swings in temperature represented by the Little Ice Age, Medieval Warm Period, Dark Ages, Roman Warm Period, etc would not and could not have happened since CO2 was allegedly stable before man started burning fossil fuels.
Lots of interesting comments but almost none address the point of my article, which is that this is an opportunity for skeptics to take advantage of.
Totally agree and must admit I am not good at this and merely luxuriate in contributing and reading the WUWT comments etc. I do however subscribe to Quora and attempt to calm down many of those stricken by the CAGW Virus. It is an interesting phycological exercise, particularly when I touch a nerve or two in the alarmist camp.
Frank Tinkler’s book “ Air of doubt” is now available free on Amazon which I suggest should be well supported and promulgated across the media if you have the mind.
OK It a hard read and probably incomprehensible to many; but the message is clear and well touches nerves in the alarmist camp. It does however need someone to explain it in Layman’s terms free of the maths where possible to point out the two basic flaws inherent in the complexities. Namely the omission of the geophysical aspects involved and the error in interpretation of the ice core data.
Perhaps some astute feedback ‘readers views’ on Amazon would be useful.
I commend it to your commenters.
Meanwhile I will pop it into Quora where appropriate and enjoy dealing with the flak! That is if the Quora Moderator permits.