Wed, 20 Oct 2021 08:16:14 +0200

Professor of Meteorology, Department of Meteorology, Stockholm University

Michael Tjernström,



The undersigned is an engineer and innovator and I have decades of experience in computing complex thermodynamic processes and running computer simulations. I have also used my mathematical tools since 2008 to keep an eye on the climate.

Understanding the climate in depth plays a crucial role in sketching the innovations needed to solve the climate crisis.

I read with interest your debate article in DN, and debate means exactly that: debate.

My opinion   is here. https://ppm.today/index.html?bilden-av-att-det-aer-foer-sen.htm

I will publish the answers/replies you give in both Swedish and English

It would be best if DN would spin on this thread.

Many thanks for future replies.

We are fighting from a disadvantage but we must help each other to change the direction of Glasgow so that climate policy really solves the climate crisis.

Best regards

Bengt Ovelius

Arlanda 2021-10-23 Sat, 23 Oct 2021 13:12:01 +0200


Hi Bengt,


On a more philosophical level, I think you are throwing around terms like "evidence", "truth" and "lie" a bit carelessly. In this context there are many hypotheses and assumptions and as and when proposed measures are presented they must be tested in their entirety with the best knowledge we can muster and what may seem obvious one day is idiocy the next.


These are what I take to be the main message of our article; that the best we can do is to stick to the knowledge that exists, but of course to constantly re-examine it. The likelihood that someone who is absolutely sure he is right is completely wrong is striking.


Is it possible to "save the climate"? Well, it depends on what you mean by that, of course. If you mean that the climate should be and remain as it would have been if we had not released significant amounts of carbon dioxide into the atmosphere, then the answer is no; we have already had a significant impact on the climate and there is no getting away from it. This impact will continue for a very long time to come. If the aim is to limit warming to 1.5 degrees, I and many others believe that it is also too late; the 2 degree target is achievable but in my view unlikely.


But if you believe that it is possible to stabilise the temperature at a reasonably reasonable level, the answer is "yes"; we will decide what that level is by deciding on measures to limit emissions.


There is no simple linear relationship between atmospheric carbon dioxide and temperature. However, there does seem to be - within reasonable limits - a fairly linear relationship between temperature and cumulative emissions; the sum of all emissions. And this is where the discussion of the "carbon budget" comes from. We know what we emitted, say X. We know reasonably well how much accumulated emissions correspond to a given temperature, say Y. Then the possible continued emissions that can be accepted to reach that temperature Y-X; that's the carbon budget for the temperature we've chosen to accept. Once the cumulative level is reached, net emissions must be zero; no climate can be stable if greenhouse gas emissions continue. And the sooner we get there, the more we can limit our impact on the climate.


For every temperature there is a carbon budget! So the second main message of the article is that there isno evidence for the argument that there is a threshold at which everything would go to hell no matter what we do. However, it is important to realise that a stabilised temperature does not mean that the whole climate system is stabilised at once; for example, the ice sheets will happily continue to melt long after such stabilisation, and the oceans will therefore continue to rise.


One suggestion for how this might happen is to put a price on emissions so that it is cheaper to capture and store carbon dioxide than to continue emitting it. The first thing that happens then is that people will start doing it; the second thing that probably happens is that they stop emitting altogether, because who wants to pay if they can avoid it?


The analysis you are asking for already exists; it is called the "IPCC report" and there you will find the best summary of the current state of knowledge. There are many thinkers - amateurs and professionals - who have views on this, but if you are asking for a scientific analysis I will have to be "boring" and refer you there.


Yours sincerely



Hi Michael,

Your reply really takes the discussion to the next level . Many thanks


YOU say "There is a fairly linear relationship between temperature and cumulative emissions; the sum of all emissions."

I fully agree with this . What you say has crucial implications for climate policy.

It is not the flow of emissions but thesum of all emissions that gives a certain global temperature after 700 years of stabilization.


The stabilised final temperature of the Earth  at a given ppm CO2 can be expressed as

t=1.443*cs*ln(ppm/275) climate sensitivity=cs=36

At cs=36 you get the best fit to both Vostok Ice Core

and to NASA 420 C at 100% CO2 = 10^6 ppm


If this function is plotted with a linear x axis, you can barely see the curve bending.

Thus it is approximately linear, just as you say.




If we assume that 1 ppm CO2 corresponds to 7.5 Gton CO2 then the same curve can be plotted (below)

with the expected stabilised temperature of the Earth as a function of the total number of Gt CO2 in the atmosphere.

My book shows that stabilization takes on the order of 700 years.

If all emissions are stopped NOW at 3100 Gton, it will take about 700 years for the Earth to reach +22 C.

Already now other factors (methane etc..) are triggered that give much more than +22 C

But the below should be a rough rule of thumb for what CO2 alone does.

The Vostok scatterplot also shows the large noise due to various random factors.





Furthermore, we can roughly say that there is the same amount of CO2 in the oceans, i.e. about 3100 Gt.

If we suck out 3100 Gt with nanotechnology, the oceans will emit so much

that we end up at about 275 ppm. You scientists can calculate this much better.

If we decide to repair the atmosphere in 20 years , starting no later than 2025, then 3100/20 = 155 Gton must be removed per year.

I show in the book that it is almost exactly this order of magnitude that also just saves the Paris Agreement


Right now we need to ignore whether this is realistic and just look at what the laws of nature require.

Climate scientists should deliver this info and leave it to innovators to

to find the technology to remove 155 Gt of CO2/year.

At present, this information is not provided and the innovators cannot get started.


We presented a possible technology at Chalmers /Graphene April 2015. It would have been a

appropriate date to start the research to be able to run sharply in 2025.

The conference was swept under the carpet because the climate scientists did not think this was needed.

This in turn was due to the huge thought error that the IPCC had last 40 years. No improvement

in sight.


But if you believe that it is possible to stabilise the temperature at a reasonably reasonable level, the answer is "yes"; we decide what that level is ourselves by deciding on measures to limit emissions.


It is precisely on this point that I think you draw the wrong conclusion. If we limit emissions to

zero already, then according to your reasoning the temperature would stay at +1.2 C

From the above curve, calculated with the above formula, it is clear that the Earth is

programmed for at least +22C. This temperature will be reached in 700 years.

The temperature does not stop, it rises linearly by 0.035 C/year until +22 is reached.

More precisely, the temperature follows the formula e^(t/RC) where RC=700 years, but we can also simplify here

with a straight line because the error will be small at the beginning.


And this is where the "carbon budget" discussion comes from. We know what we emitted, say X. We know reasonably well how much accumulated emissions correspond to a given temperature, say Y. Then the possible continued emissions that can be accepted to reach that temperature Y-X; that's the carbon budget for the temperature we've chosen to accept.


By looking at exactly the same curve in the range 275 to 400 ppm, we get the answer to the carbon budget


In 1700 it was 275 ppm and everyone agrees that a true carbon budget exists.

In 1895 it was 285 ppm and the +2C programmed temperature has been reached. If all emissions are stopped we will have +2C after 700 years

So the carbon budget was exhausted in 1895.






I can believe it all boils down to you using climate sensitivity=3 in all reasoning and me using 36. Here lies the very root of the difference in opinion.

Therefore, I can only refer to how I prove that cs=36 is approximately the correct value,


This is the "trap" that is not immediately obvious, but illustrated here





On a more philosophical level, I think you may be throwing around terms like "proof", "truth" and "lie" a bit carelessly.

I can agree with you on this, but I mean that I am presenting the chain of evidence down to the last detail.

Therefore, everyone is invited to put their finger exactly on the right point in the chain of evidence or mathematics.

Thus truth and falsehood are tested in a logical and structured way!!


Since 2008, I have always said: everyone will be happy if I am wrong, even me!

In fact, I would like the temperature to stop when the emissions are stopped.

But the age of wishful thinking is over, say thethree authors of "Net Zero" is a dangerous trap".

Best regards

Bengt Ovelius



On 2021-10-24 21:29, Michael Tjernström wrote:

Berlin 2021-10-24


Hello again,


Two short answers and two reflections:


1) Temperature is not linearly dependent on CO2 content in ppm; it is linearly dependent on the accumulated amount of carbon emitted in Gigatons. The CO2 content depends on a variety of factors, all of which depend on others, and the linear relationship is not a law of nature; it in turn depends on a lot of factors and only applies under conditions reasonably close to those we are in. No one imagines that a system as complex as climate can be captured in a simple regression on carbon dioxide levels. Nothing short of net zero emissions can lead to a stabilized climate; as long as emissions are > 0, carbon dioxide levels and hence temperatures increase.


2) It doesn't take 700 years for the effects of what we emit today to be realized; it happens fairly quickly. Were we to magically manage to stop emitting carbon dioxide today, the temperature would probably rise another tenth or so, then stabilize within a few decades, and then painfully slowly begin to decline as the carbon disappears from the atmosphere extremely slowly. It's that reduction that would take perhaps on the order of 700 years, so you've got the timescales backwards. Emissions are no more than a couple of hundred years, so if 700 years was the relevant timescale we would hardly have seen any difference yet.


1) I can listen to your arguments, but when you start parroting chains of evidence I get suspicious. Thousands of scientists around the world spend all their working time trying to jointly understand the climate system and every week someone finds something new we didn't yet understand. And then you come up with the definitive proof; understand if I find that gut-wrenching.


2) Of course it would be good if we could capture carbon dioxide from the atmosphere and in the long run it might be possible. But the simple, quick and guaranteed effective method is to stop emitting. Better not to crap down than to crap down first and clean up later.







Hi Michael

Many thanks for your reflections,

I can answer very briefly with the following animation. The cloud of points is from Vostok ice cores,

The stick  cs=3 is NASA's measurements a hundred years back. Why does this stick stand out ?

Well, because the points need much more than 100 years to stabilize. I think the IPCC has missed the dynamics

and stared blindly at the stick, which indeed has climate sensitivity = cs=3 in the short perspective.

The slope of the stick reveals the time constant RC which is between 600-800 years. One way to calculate RC is to look at the last point

on the stick, where we are. NASA measures that the Earth is currently rising 0.035 C/year

The time for the point  to stabilise is then about 22/0.035 = 700 years. A rough rule of thumb that seems correct.

With these rules of thumb I made a forecast in 2008, after discussion with the top management of the IPCC

This forecast was exactly right until 2021 while the IPCC failed completely ( +2C /450 ppm /year 2100 )

I have over the last 14 years looked at this from different angles and it seems correct.

When the stick is turned up in harmony with the cloud

the climate sensitivity is around 36. I see this as a complete proof and the proof is based on facts (Vostok+NASA)

A climate proof can't get any heavier than that.


Best regards Bengt

PS From this proof it is a straight mathematical path to the next proof which says that Zero Emissions2045 is ineffective in terms of temperature response, Whatever we do in established climate policy the earth is rising faster than 0.035 C/year. There is no way to stop the temperature rise. We need to take much stronger action, NOW. The above evidence is the exact opposite of what you say, quote:

"If we were to magically stop emitting carbon dioxide today, temperatures would probably rise another tenth or so, then stabilize within a few decades"


I take the same line as Vinod Khosla: I do the most good by being brutally honest.


Many thanks for this discussion that moves the theme forward. Other authors are also welcome to comment,

here or via DN.



Potsdam 2021-10-25 Mon, 25 Oct 2021 07:06:37


Hello again,


I think we should end this exchange of views. I believe in the scientific method and thus in the IPCC, which stands for a summary of the state of knowledge. I don't believe anyone holds the whole truth, nor that anything can be proven. The moment it becomes important to "prove" and "be right", the whole discussion locks up and it becomes impossible to move forward. Instead, you should try to penetrate your own arguments and seek to find how or why they might be wrong; that's how the scientific method works. So this will be my last post in this discussion.






Hi Michael


I am not sending any more emails as per your request. But I still reply to your email here on the web.


"I believe in the IPCC" you say," Thereby you lock the whole debate.

The IPCC is the axiom and foundation of your worldview.


By the deep trust in our professors you drag the press and the politicians with you

who then don't dare to critically examine the IPCC.


The three scientists say:


Scientists are one of the most trusted professions. Trust is very difficult to build and easy to destroy.

But there is another invisible line, the one that separates maintaining academic integrity and self-censorship. As scientists, we learn to be sceptical, to subject hypotheses to rigorous testing and interrogation. But when it comes to perhaps the greatest challenge facing humanity, we often display a dangerous lack of critical analysis.


I myself present in a single image (above) the crystal-clear proof that the IPCC is wrong

and that the IPCC has been calculating the wrong climate sensitivity for 40 years.

This deadlock is stumblingly close to being the end of civilization.


You say: the moment it becomes important to "prove" and "be right" the whole discussion locks up and it becomes impossible to move forward.


I think  the opposite is true:

Most of the discussion in your article in DN is about superficial claims. For me it has been important that

all claims to be provable and that it is crucial to seek the truth, i.e. see it as a

ultimate goal to "be right".


So you see the evidence as a threat and reaching the truth, i.e. pursuing to be right, as an equal threat.


You say: "Instead, you should try to penetrate your own arguments and seek to find how or why they might be wrong; that's how the scientific method works"


I have been penetrating my own arguments for 14 years.

Together with a scientist we tried to warn the IPCC top management in May 2008 and the argument

included this graph of the results of our research.


The picture is crystal clear. Earth's temperature will continue as if nothing happened when all emissions are stopped in 2010.


The IPCC's red line follows your beliefs exactly and we can now see in retrospect that it was wrong.




The IPCC's top management received this warning in May 2008 and it looked at this worryingly

and promised to work on this hypothesis among colleagues at the very highest level.


Now, 14 years later, the entire world's climate policy is based on the same catastrophic error:

The latest report promises that the temperature will stop. A more accurate picture is on the right,

where no curve can be slower than the current 0.035C/year.


On this error, the IPCC is driving the whole world to destruction.





You write : I think we should end this exchange of views

This can only be interpreted as you having no scientific arguments to counter my evidence.


I regret that you are throwing in the towel, but I deeply respect your choice.




Best regards





Hello again


At your request the discussion is closed .

I have written a concluding reply which can be found here



Unlike most of the other article authors, you have taken part in the discussion and I am deeply grateful for this.

You 8 authors wrote "Debate article" and of course wanted debate. In doing so, I have to some extent fulfilled your wishes,


Thank you and best regards

Bengt Ovelius

Sundsvall 2021-11-05


Hi Bengt,


I don't understand that anyone has thrown in the towel. Instead, I note that a debate does not consist of repeating the same arguments over and over again, and therefore I did not reply to your last email.


In my first reply I related to the enormous amount of research and results presented in the IPCC report, which is a summary of the state of knowledge at the moment. It presents cutting-edge research on the climate system and climate sensitivity by the world's leading climate scientists.


Your response to this was to repeat your earlier assertions without commenting on what, in your view, is wrong with the IPCC's conclusions and why, e.g. on climate sensitivity. You write that you believe the IPCC lacks scientific support for its conclusions but do not explain how. Since the IPCC bases its conclusions on what has been published in peer-reviewed scientific papers, that is a pretty serious indictment, not only of the IPCC but of the whole way in which scientific knowledge is constructed. Therefore, one might wonder how you carried out your calculations, what models they are based on and where you published these results.


Therefore, I did not find it useful to continue the email exchange. I still don't.


Yours sincerely


Hi Michael

Yes, that is an extremely serious accusation against the IPCC.

§1. The very basis is that the IPCC for 40 years calculated the wrong climate sensitivity=3 . The correct value looks to be about 36.

The full justification can be found here https://ppm.today/index.html?climate-sensitivity.htm

§2. This IPCC error makes very many calculations and projections wrong: The most serious is that the IPCC can say that the temperature will stop where emissions stop. My complete evidence is in these ten lines.


1.That's 3000 Gtons of CO2 too much and it causes +0.035 C/year. Regardless

2.whatever reductions are made, there are 3,000 Gt left. The absolute

3.minimum temperature in 2100 if emissions stop today is

4.(0,035 * (2100-2021))+1,1 = 3,9 C

5.Therefore, neither NetZero 2050 nor NollUtsläpp2045 can work

6.It will be at least +3.9C in 2100, probably much more, whatever we do in

7.current climate policy NetZero as long as 3000 Gton remain.

8.Limiting to +1.5C or 2C with emissions reductions is a physical impossibility.

9.The IEA pledge of +1.8C is equally impossible.

10.Climate policy needs to look completely different and this discussion should already have started in Glasgow


The incorrect value from the IPCC on climate sensitivity makes dozens of conclusions wrong. Those who believe in 3 do not see these errors.

Here is the background data https://ppm.today/index.html?bilden-av-att-det-aer-foer-sen.htm

Examples of errors as a direct mathematical consequence of climate sensitivity=3 instead of 36











> Therefore, one may wonder how you carried out your calculations, which models they are based on and where you published these results.


how you carried out your calculations See above, §1,§2 which gives a complete derivation

what models they are based on See above, §1,§2 which gives a complete models, mathematically anchored

where you published these results https://ppm.today/

I have shown with extensive links, references, models and calculations that your article is wrong on many points


You authors have not provided a single rebuttal, or a single model to support the article, not a single calculation. Since all this is missing, please feel free to review my motivation and evidence and indicate what is wrong.

I have to say on "rock solid" grounds that you authors have not shown that you can stand for the content of the article.


It is called a "debate article" :  I have tried to fulfill your wishes for debate.

DN is not responsible for the article. "This is an "debate article" in Dagens Nyheter.

The writers are responsible for opinions in the article."

So the writers must be responsible for the debate that you yourself wanted to provoke. This debate is also very important

and everyone should be deeply grateful that the debate has begun.

Best regards

Bengt Ovelius



Uppsala 2021-11-15




No, there is no reason to believe that discussion per se, without knowledge or insight, would help. A science-based solution to the climate problem requires that we understand how the climate system actually works.


We imagined that we had some insight into this, which gave us the reason to write the opinion piece. Now you claim we are completely wrong but fail to explain yourself.


I would therefore suggest that you summarise your hypothesis and develop the reasoning in a scientific paper and submit it to some respected journal so that it is properly peer reviewed. After all, that's how we work; not with slogans and links to websites of unclear origin.









Hi Michael,

Thank you for your reply.

Readers will have to decide whether you have once again thrown in the towel.


The picture below describes how the IPCC manages to miscalculate 60 years by using the wrong climate sensitivity=3

Absolutely all ordinary people understand this but I have yet to come across a single professor who does.

The climate experts have cheated ordinary people and our politicians out of their money and this error can lead to

the end of civilization. I am still waiting for your comments. When will there be an apology from the IPCC

and from the parade of professors who blindly follow the IPCC? Where was the expertise when all these errors moved into

Government Bill 20216/17:146 ?





A high school physics teacher said: This is elementary and does not need to be discussed. Temperatures will continue when emissions are stopped. Everyone understands this but I have yet to come across a single professor who understands.

Are you professors to remain the only ones in society who do not understand the elementary ?


It is not my job to write scientific papers. You can make use of tips from society for new breakthroughs.

The tips I give are clearer and better deduced than the references to scientific papers you have given.

Surely this is a brilliant derivation of climate sensitivity that outshines anything you can find in COP26 ?



An example of undeveloped area is a theory of climate sensitivity=cs which is the basis for almost all calculations and projections.

The level of knowledge that the IPCC exposes about cs in COP26 is taken 40 years back in time. It is on a par with the celebration of an even more erroneous climate sensitivity  expressed by this year's Nobel Prize.



The earth is like a boat that has had a small leak for 200 years.

It is now on the verge of sinking. Glasgow has been about plugging the hole

even though you know it won't be fixed in the next 50 years. There is every indication that the hole will increase in size instead.

Right now the amount of water in the boat is increasing 1% per year.


My whole point is to say that the boat needs to be bailed( 200 Gton/year). Because I am an innovator

I also have detailed suggestions on how this might be done. This needs to be in operation by 2025.


The technology has been discussed at Chalmers/Graphene Assembly 27 Apr 2015 and researchers gave the thumbs up.


This had the potential to be the largest industrial project in the country. Had it succeeded, it had the potential

to solve the ENTIRE climate crisis. It was stopped because it was not needed. The IPCC had promised that +2C would not occur until the year 2100. So no hurry. Now we know that +2C will happen 63 years earlier.

Climate experts must take full responsibility  for sinking this project (and many others?) by giving

the world a false climate picture.

You are busy defending a false climate picture and are therefore actively obstructing the innovations that are within reach.



Why do professors seem to be afraid of the truth that we must have to build the future ? Is it the peer pressure from the IPCC that is so intense ? Is the corridor of opinion so narrow in academia?


You have not done a very good job of explaining yourself or defending the article. Nevertheless, the discussion has moved the topic forward because I am now more confident than ever that my views will win, even if it takes a few more months.

I offer warm thanks for the discussion.



Soon everyone will be left unprepared and helpless when it is seen that trying to plug the leak was the wrong strategy,

while new holes appear.

We need to take a much firmer hand and start scooping. It's as simple as that. Soon everyone will understand this - except the professors.(??)

But there is still time for you to put yourselves at the forefront and exercise leadership based on truth.

You have the platform to make a transformative difference.


I made a perfectly correct forecast 2008-2021 using the "correct" climate sensitivity cs=36

The IPCC's forecast for the same time was a disaster because it used cs=3 (see 1-a graph in this email)


Below is my graph for the near future, calculated in the same way.

In 2027 the Paris Agreement falls, harvests fail, more and more countries start to look like Syria. Climate surprises - no one can say what will come.


In the article you want to convey the insight that the risk of young people.... dying from climate change ...is negligible.

At the same time you celebrate cs=2.3 which puts +2 well beyond the year 2100.





MVH Bengt Ovelius






On 2021-11-15 14:01, Michael Tjernström wrote:

Uppsala 2021-11-15




But there is no physics in what you describe; just curve fitting! If you force a logarithmic curve through a finite number of points, everyone knows that the end can end up anywhere.


You're obviously completely convinced, but what you write contains no insights into how the system works - just curve fitting where you've already assumed at the outset that the curve looks a certain way.


That doesn't hold up, then you can call it me "throwing in the towel" as many times as you like; it doesn't matter, to you or me.




Hi Michael,


>But there's no physics in what you describe; just curve fitting! If you force a logarithmic curve through a finite number of points, everyone knows that the end can end up anywhere.

Answer: I assume you are thinking of this diagram:

We have a logarithmic line t(ppm) =1.443*cs*ln(ppm/275) cs=36 that fits the cloud from Vostok, that fits the known points (275.0) (285.2) and that fits NASA 420C@100%Co2

We have a logarithmic line t(ppm) =1.443*cs*ln(ppm/275) cs=3 which fits nothing more than the erroneous points (450.2) from the IPCC blue sign which in turn gave an erroneous climate science. From this erroneous line, the IPCC proves that NetZero can work.


There is lots of physics in this with evidential power. This is real science. Then this is confirmed by completely different observations, such as the Eemian tracks.

From this line cs=36 I can prove that NetZero cannot work.

So you prefer the line cs=3 where nothing fits and where the earth only gets +36C at 100% CO2. Or the Nobel Prize cs=2.3 where the earth only gets +27C at 100% CO2.?

I invite you to defend cs=3 by citing more factors in support of cs=3 than I cited in support of cs=36. Then we will have a meaningful and structured discussion. I would be very happy if you are right because the whole climate threat in one fell swoop becomes 36/3 = 12 times less aggressive.


MVH Bengt

Hej Lennart

You wrote : It looks really bad. What are you going to do about it? It is indeed a scandal if the IPCC has calculated so wrongly.

Answer: What are WE going to do about it?

I suggest a debate article where everyone is involved. This collection of excellent expertise can achieve peer-review in a few days.

My draft opinion piece is here:


If my suspicions are correct, Sweden can achieve a world-leading position in climate work - and we can quickly get a working climate policy.

Feel free to amend and supplement so that everyone is happy. Once the debate gets going, my website can start focusing on the solutions, which is my job.

It will then follow IPCC chief Hoesung Lee's wishes: he wants to shift the focus from what causesclimate change - to solutions.



Suggested authors

John Hassler

Rodrigo Caballero

Deliang Chen

Per Krusell

Thorsten Mauritsen

Jonas Nycander

Michael Tjernström

Lennart Bengtsson

Frida Bender

Bengt Ovelius


On 2021-11-14 10:42, Lennart Bengtsson wrote:



It looks really bad. What are you going to do about it? It is indeed a scandal if the IPCC has calculated so wrong. The possibility still exists of course that it could be you who has thought wrong. At least I can't follow your reasoning.


Lennart Bengtsson

On 2021-11-17 12:38, Michael Tjernström wrote:

Stockholm 2021-11-17

Hello again,

Thanks, but I think I'll "throw in the towel" and pass.


On 11/17/2021 1:05 PM, Bengt Ovelius wrote:

Hi Michael,

You use climate sensitivity=3 in all your calculations and conclusions. Behind the whole debate article and its conclusions is cs=3.

I had hoped to get your defense of the figure cs=3 as it would also defend the article you contributed to.

German President Frank Walter Steinmeier has said that a functioning democracy requires open discussion and courageous citizens.

On this path, we may be able to gain an edge over non-democratic countries.

You also wrote: No, there is no reason to believe that discussion alone, without knowledge or insight, would help. A science-based solution to the climate problem requires that we understand how the climate system actually works. What is knowledge and insight ? Is it the IPCC's conclusions?

This is interesting because what you are suggesting provides a locked system. The IPCC cannot be scrutinized if the IPCC is also a truth-teller. This is why I have seen scientists ever since 2001 failing to warn that the Earth's temperature will continue at zero emissions. Those who understand how the climate system actually works seem to have misunderstood crucial facts and don't want to argue.

Therefore, it would be honorable for you to do a peer review of my draft and justify what, if anything, is wrong.


Then you also respond to the high school physics teacher who said: It is elementary and beyond discussion that temperatures will continue once emissions are stopped.

The Swedish people need to be informed on the issue that determines the future of our children. With climate sensitivity = 36, we have acute danger to the lives of millions of children in the next 10 years.

Best regards Bengt


On 2021-11-17 13:30, Michael Tjernström wrote:

Stockholm 2021-11-17


Hello again,


There are only estimates of climate sensitivity and different methods give slightly different results; exactly which value is the right one nobody knows and the IPCC gives a likely value and a spread based on several different scientific methods. This is a relatively big issue in the IPCC report and many scientists have been working on this problem in a scientific way for many years; among us, Thorsten is probably the expert.


I suggest you start by reading the attached article. To then, as you do, come up with a simple curve-fitting and conclude with equivocation that the IPCC has "got it all wrong" seems to me to be a bit gutless. There is of course one - or more - physical reason(s) for the distribution of points in a graph, and a curve fit can sometimes be useful. But by itself it reveals no physics and does not provide any understanding without further interpretation based on known physics.


This will have to be my very last post in this debate.






Many thanks for "An Assessment of Earth's Climate Sensitivity Using Multiple Lines of Evidence" PDF (92 pages)

I have now read the first chapter which seems to reveal that the whole report is written in the spirit of 150 years being a long time and the expected climate sensitivity =3. With these two basic assumptions I suspect the authors are backing themselves into a corner. This trap is brilliantly cruel and difficult to uncover. In the end, you get a complex model that doesn't fit reality. S=3 gives +2C at year 2100 and 450 ppm. Another conclusion of cs=3 is that temperature stops when emissions stop. This requires a time constant close to zero and an extremely low climate sensitivity. Both results are wrong. Attempt a brief analysis here:


John, thanks for your reply.

You write: discussion requires listening to each other's arguments and commenting on them.

I agree 100%. If I missed any comment, I will be happy to go back and try again.

You write: As I understand it, you mean that the slope of the relationship between CO2 content and temperature in historical data can be used to draw conclusions about climate sensitivity when carbon dioxide content is increased by human emissions. I have argued that this does not work if there exists a causal relationship in the opposite direction. I illustrated this with a simple example. I have not received any comment on this other than that it was interesting. Nor have you claimed that I misunderstood your arguments. Hence no discussion arises.


I responded that "What you say here is extremely valuable" and outlined two such natural experiments that are completely outside of "causation"

This is exactly what you were calling for, I suppose. I thought it was a good and fruitful discussion for which I thank you. The discussion is at the bottom here



I am struggling with this discussion with the sole aim of getting an accurate climate description so that the innovators can do their job.

Furthermore, I would be sincerely happy if I am wrong about climate sensitivity=36 .


High school physics teachers would also like to know how temperatures can stay when emissions stop.


Best regards



I have now read through a large part of the scientific paper

"An Assessment of Earth's Climate Sensitivity Using Multiple Lines of Evidence"

It further confirms that the paper deals with non-stabilized values which gives the wrong climate sensitivity in the end.

My detailed comments can be found here (looking forward to comments )




It's time to start calculating with climate sensitivity =36, so we can get accurate projections and a workable climate policy,

in my very humble opinion. The evidence is (from my point of view) overwhelming.

It is urgent to get the truth on the table because the whole climate policy stands or falls on climate sensitivity.

Rockström expresses the same concern in SVD. Already at climate sensitivity 4 the CO2 budget falls...etc...


At the same time I would be sincerely happy if I am wrong because S=36 requires hefty grabs to handle while NetZero policy falls.


Best regards

Bengt Ovelius