German Paper: “A Mild Additional Temperature Rise Of Around 1°K”… Drop Not Excluded By 2100!

From the NoTricksZone

By P Gosselin on 6. March 2022

In its most recent video, German site Die kalte Sonne here looks at a paper on CO2 climate forcing by Stefani 2021: Solar and Anthropogenic Influences on Climate: Regression Analysis and Tentative Predictions. The results point to only a moderately warming planet up to the year 2150.

Figure 9d of Stefani 2021. Scenario with a mild decarbonization scheme

To hype up climate warming alarm, IPCC scientists like to exaggerate CO2’s power to trap heat and warm up the atmosphere. But with every assessment report that the IPCC issues, the estimated value by which CO2 warms the planet steadily gets reduced as the observed warming keeps lagging behind what earlier models predicted.

In his paper, Frank Stefani and his team at the Helmholtz Center, Institute of Fluid Dynamics in Dresden, Germany looked at the impacts by CO2 and solar activity.

On average 1.1°C warming

Using double regression, the scientists evaluated linear combinations of the logarithm of the carbon dioxide concentration and the geomagnetic aa index as a proxy for solar activity. They reproduced the sea surface temperature (HadSST) since the middle of the 19th and ended up with a a climate sensitivity (of TCR type) in the range of 0.6 K until 1.6 K per doubling of CO2. The midpoint of this range is 1.1°C, a value many critical climate scientists have already estimated earlier, and thus far below the IPCC scary estimates.

The paper’s abstract elaborates further:

The solution of the double regression is quite sensitive: when including data from the last decade, the simultaneous occurrence of a strong El Niño and of low aa values leads to a preponderance of solutions with relatively high climate sensitivities around 1.6 K. If these later data are excluded, the regression delivers a significantly higher weight of the aa index and, correspondingly, a lower climate sensitivity going down to 0.6 K. The plausibility of such low values is discussed in view of recent experimental and satellite-borne measurements. We argue that a further decade of data collection will be needed to allow for a reliable distinction between low and high sensitivity values.”

Imminent temperature drop cannot be excluded

They write further:

We make a first attempt to predict the aa index and the resulting temperature anomaly for various typical CO2 scenarios. Even for the highest climate sensitivities, and an unabated linear CO2 increase, we predict only a mild additional temperature rise of around 1 K until the end of the century, while for the lower values an imminent temperature drop in the near future, followed by a rather flat temperature curve, is prognosticated.”

Prof. Fritz Vahrenholt also recently discussed Stefani’s paper, see here.

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Tom Halla
March 7, 2022 6:12 am

This would also be consistent with Lewis and Curry, who used the inflated GISS temperature records, so their estimate of sensitivity is an upper bound.

Reply to  Tom Halla
March 7, 2022 7:13 am

Sensitivity matter no more.
Europe is planing for ‘Climate Change Pass‘.!

Reply to  Vuk
March 7, 2022 7:59 am

“We used to be a fairly sizable group of countries arguing for more ambition. We’re not a huge number left,” one EU diplomat said.


The above statement, if true, cuts right through all the bloviation.

Reply to  commieBob
March 7, 2022 8:24 am

It was said,about 5min before I posted comment, at the press conference attending the UK’s PM, Canada’s PM and Holland’s PM, held in London. All three did indicate that it is essential to protect industry and consumers, might last until renewable suppress the Russian dependency.

Reply to  Vuk
March 7, 2022 1:01 pm

Just until we flatten the curve, right?

Reply to  Scissor
March 7, 2022 1:13 pm

It might take a while to flatten this curve

Reply to  Scissor
March 7, 2022 1:37 pm

France may be country to consider moving to:
French Finance Minister Bruno Le Maire has said that the government plans to spend over 20 billion euros to combat the effects of rising inflation on purchasing power. Speaking on Franceinfo he estimated that the freeze on gas prices would cost the government about 10 billion euros this year, the limit on electricity prices about 8 billion euros and compensation for inflation 4 billion. 
Hey, BoJo, French are “having their cake and are eating it”.
You did promise it to Brits too after the Brexit, so can we have the same or at least some of this French stuff ?
French do like cakes not so the guillotine.
Vive le Choupinet !
Vive le Socialisme !
Vive la France !

Reply to  Vuk
March 7, 2022 4:18 pm

Going to have to spend more money to take care of inflation. Sounds like something FJB would say.

Bob boder
Reply to  Vuk
March 7, 2022 8:09 am



March 7, 2022 6:25 am

CO2’s power to trap heat and warm up the atmosphere – article

Just a question: how come none of these people ever address the other heat trapping gases such as water vapor, nitrous oxide, and methane, all of which trap more heat than CO2????

Poor ol’ CO2 gets hammered all the time, while the others are ignored. This, all by itself, is the reason I can’t take the Greenbeaners and Warmunists and others of their ilk seriously.

I’m gonna go fix my breakfast and enjoy watching the snow falling in my AO. S’posed to snow later on, too, and then again on Wednesday. Golly gee, globull warming sure is slow to arrive here!

Dudley Horscroft(@dudleyhorscroft)
Reply to  Sara
March 7, 2022 7:55 am

CO2 is the only one to have a substantial increase in concentration. Water vapour has been approximately constant over the last few 1000 years since the end of the last ice age, and even at low levels is in sufficient concentration as to have a constant effect. The others are negligible warmers.

Ergo, concentrate on CO2.

david chorley
Reply to  Dudley Horscroft
March 7, 2022 8:48 am

water vapour is at 10,000ppm, climate worriers are looking at a change from 380ppm to 420ppm in CO2 which absorbs and re-radiates in narrow bands in the IR and adds 2.75 Watts/m^2 (total, not the increase) to the infra red warming trend in areas that are warmed by the sun at 280 Watts/m^2. How simple is that. How do people not realize that the CO2 dog-and-pony show is nonsense from the word go?

David Pentland
Reply to  Dudley Horscroft
March 7, 2022 9:40 am

Water vapor is crucial to the global warming hypothesis. CO2 by itself is insufficient without the “positive feedback” of water vapor.

Dave Fair
Reply to  David Pentland
March 7, 2022 10:34 am

UN IPCC CliSciFi modelers have shifted away from aerosol dampening and water vapor amplification since real science has shown neither of those effects. They are now playing with clouds. It will probably take a decade for real science to catch up with the new modeling fantasies. In the meantime, UN IPCC AR6 had to throw out a number of new models because of radically hot, unrealistic results.

David Pentland
Reply to  Dave Fair
March 7, 2022 10:57 am

Thanks Dave, I had no idea.
Talk about moving goalposts.
I don’t understand how this ideology survives without a sound scientific basis.

Clyde Spencer
Reply to  David Pentland
March 7, 2022 3:46 pm

It survives because supporters and apologists (like the MSM) control the dialog and the general public is easily persuaded by sound bites like, “9 out of 10 scientists recommend you believe the claims.” You, get away from that curtain! Stop that!

Reply to  Dudley Horscroft
March 12, 2022 3:19 pm

I’ll call your CO2 and trump you with water vapour … where is the ‘hot spot’ … seems that water vapour ‘flushes’ you out 😉

Matt Kiro
Reply to  Sara
March 7, 2022 8:35 am

I feel a better question is why we don’t measure temperature from absolute zero? Going from 288 to 289C is alot smaller percentage increase than from 15 to 16.5 . Or when they use an anonomly graph that shows negative values! Those make it seem really scary.

Joao Martins
Reply to  Matt Kiro
March 7, 2022 10:34 am

That is why they don’t even use Cent Or Fahr and use instead deviations (from average or whatever).

Reply to  Matt Kiro
March 7, 2022 12:28 pm

Fine by me! But obviously, it would interfere with their ‘results” and is therefore useless. 😉

Gary Pearse
Reply to  Sara
March 7, 2022 1:09 pm

Sara, the big irony will be when they back away from the green psychosis and nothing noteworthy happens to the climate. Even better (but at my age I’m not hoping for it) we seem to be heading for a 30-40 year cooling through natural variations.

There have been a few forecasts of this from early 2000s. Indeed, climateers have been bending the temperature up as they worried about the Dreaded Pause. James Hansen ‘invented’ the business of fabricating temperatures upward for “the cause”. By 2007, the highest temperatures where still in the late 1930s. 1998 super el Niño did not set a new record! They had to push the late 30s-40s temperatures down by more than 1°F to ‘fix’ this and then had to cook their way out of the “Pause” that followed. There is little doubt that the true high temperature stand is still late 1930s.

Dyan Davison
Reply to  Gary Pearse
March 8, 2022 12:14 am

Wrong…..there have been predictions since 1970 (Ehrlich etc) , Prince Charles (on a regular basis), George Monbiot (ditto) and others. None of which have come true. What has been a success is that people still believe this nonsense. The same for masks. I despair of the intelligence of the public. I am regularly called a climate denier (what ever that is because I can’t deny we have a climate – haha )- . It is so exasperating.I am now in my mid 70s and so should I bother with all this. However my local council has set net zero by 2030!!!!! In recent storm Arwen when we had no electricity here for ten days, a local housing charity had to justify taking out fires and replacing with heat source pumps. Houses took three weeks to get back to temperature and they used fan heaters and all sorts of other stuff to stop old people from dying. Great!

Reply to  Dyan Davison
March 8, 2022 4:39 am

Throw it back at them. They are natural variability deniers!

re. Chuckie … Canada should dump the monarchy when the queen dies.

Clyde Spencer
Reply to  Sara
March 7, 2022 3:41 pm

One might be cynical and say that the focus is on CO2 because it can be claimed (falsely) to be responsible for the warming, and, being created by humans, can be reduced. For those who have another agenda, CO2 makes a good tool for social changes.

March 7, 2022 6:28 am

They reproduced the sea surface temperature (HadSST) since the middle of the 19th and ended up with a a climate sensitivity (of TCR type) in the range of 0.6 K until 1.6 K per doubling of CO2.

if this is true we’re not 500,000 years away from the next glaciation like IPCC and NASA insist

instead we’re teetering on the edge of an abyss and the rope we were holding onto just turned out to be attached to nothing

fortunately by 2200 controlling the climate may be fairly trivial engineering

let alone the strongest glaciating periods in around 2000 years according to CE’s Javier

Last edited 2 months ago by TallDave
Reply to  TallDave
March 7, 2022 7:07 am

fortunately by 2200 controlling the climate may be fairly trivial engineering”

I think you are correct although not so much the climate, but the energy reaching our wonderful planet – simple reflectors for example. The climate will do what it always does.

It won’t look good for the nitwits in London, Washington and Canada though who think it’s a good idea to farcically attempt to make those places cooler.

Reply to  philincalifornia
March 7, 2022 11:38 am

yeah by 2200 our concerns will probably seem even more naive and quaint than those of 1800 seem to us today

with limitless AI labor at their disposal, 100 billion posthuman sentients wormed into tunnels deep in the crust might view the surface as a museum park

Last edited 2 months ago by TallDave
Reply to  TallDave
March 7, 2022 6:44 pm

See post ‘Cold Comfort’ at the TCW Defending Freedom blog. We have the technology to avert an ice age – the Greens won’t like it.


Reply to  Julian Flood
March 8, 2022 1:52 pm


used to think an Ice Age would doom us, but now seems likely in the long run we’ll just move agriculture indoors/underground anyway, since LED lighting is so efficient now and people like open areas for other things

a vertical hydroponic system with CO2 injection can produce astounding amount of calories from a small footprint

there are already commercially competitive indoor strawberry operations

Last edited 2 months ago by TallDave
Steve Case
March 7, 2022 7:04 am

We make a first attempt to predict the aa index and the resulting temperature anomaly for various typical CO2 scenarios. Even for the highest climate sensitivities, and an unabated linear CO2 increase, we predict only a mild additional temperature rise of around 1 K until the end of the century, while for the lower values an imminent temperature drop in the near future, followed by a rather flat temperature curve, is prognosticated.”

So, I can look forward to Norah O’Donnell breathlessly reporting on CBS news tonight that a new study shows that Climate Change won’t be as bad a previously thought!

Ha ha ha ha ha ha ha ha!

Bob boder
Reply to  Steve Case
March 7, 2022 8:08 am


Richard M
March 7, 2022 7:04 am

One thing missing from this analysis is the effect of natural ocean cycles such as the AMO and PDO. They are likely responsible for about .6 C of the current warming. If you remove this from the estimate of 1.1 ± .5 C you end up with a range between 0-1 C. Some of that is probably due to UHI infecting the Hadcrut4 data.

This is reasonable once a person realizes that CO2 has almost no warming capacity left. All of the 15 micron IR available to CO2 from the surface is absorbed within 10 meters. The claims that CO2 still warms at high altitudes through raising the ERL (effective radiation level) does not stand up to critical analysis.

This means that all the warming capability from CO2 occurs within this lowest 10 meters. However, since this is well within the atmospheric boundary layer (ABL). That potential warming is lost due to equilibrium processes.

Richard M
Reply to  Richard M
March 7, 2022 7:20 am

Here is the logic of why the ERL can not increase.

If we look at the atmosphere as a set of concentric layers the layers above will NOT absorb all the radiation from below. Look at two adjacent layers.

The layer above radiates X amount of energy downward and all of it can be absorbed since there are more CO2 molecules below. The lower layer radiates X+Y amount of upward energy due to having the extra CO2 molecules. The extra molecules are simply the effect of gravity on the density of the layer.

The higher layer can only absorb X amount of that energy based on its number of CO2 molecules. The extra Y energy has nowhere to go. It’s kind of like a round of musical chairs where the higher layer has fewer chairs. Only a subset of the people looking for chairs will find them.

Note that the higher layer was completely saturated by the X energy radiated to it from the lower layer. It has no capability to absorb energy from any other layer further below it either. Think of musical chairs again. The chairs keep getting removed round after round as you go up. The higher layer cannot provide a seat for all the people moving up from the previous layer let alone anyone who didn’t make it there from previous rounds.

This means the Y energy lost ends up going directly to space. Lets assume X=8 units emitted by the lower layer and 6 units are absorbed by the next layer up. This results in a loss of Y=2 units or 25% of the available energy.

Now consider what happens with 2XCO2. You now have X=16 units emitted by the lower layer and 12 units absorbed by the next layer up. This is a loss of Y=4 units which is once again 25% of the available energy.

This is why the emission height does not change. The % of energy loss is independent of the amount of energy. The loss rate is a function of the change in density.

Even though the atmosphere is not separated into layers as in my example, the general trend is the same. Energy is lost continually as it rises since fewer CO2 molecules exist the higher one gets.

March 7, 2022 7:08 am

I am no scientist, but I get the distinct impression that this morning has two articles with useful modeling — the fire ants and this. Maybe things are looking better.

Bob Weber(@coolclimateinfo)
March 7, 2022 7:10 am

“5. Conclusions and Outlook
In this work, we focused exclusively on a quasi-instantaneous, i.e., TCR-like, climate
sensitivity on CO2. As for ECS, we agree with Knutti et al. [3], who opined that “(k)nowing
a fully equilibrated response is of limited value for near-term projections and mitigation
decisions” and that “(t)he TCR is more relevant for predicting climate change over the next
century”. In view of the millennial relaxation time scale underlying the concept of ECS, we
caution that any intervening grand minimum of the solar dynamo would undermine the
predictive power of our model. Moreover, we fear that the huge Milankovitch drivers [98]
will—perhaps much too soon—massively interfere with the solar and anthropogenic factors that were considered in this paper.” [my bold]

Too many caveats in the paper imo. They didn’t mention accumulation of absorbed solar energy in the ocean, favoring instead quasi-instantaneousity, which means little to no solar absorbed ocean heat accumulation over time, similar to IPCC thinking.

comment image

comment image

This is tantamount to treating the ocean surface like a reflective mirror, when in fact it does absorb at depth, leading to a decent lag in ocean surface temperature wrt sunspot activity.

comment image

If their model can be undernined by a GSM then it’s not a very good model to begin with, and any conclusions from it can be ignored. I printed the paper out, and tomorrow it will become fire-starter, it’s only real value.

Bob boder
Reply to  Bob Weber
March 7, 2022 8:07 am

The politics have changed so the narrative needs to change, funny how Germany works isn’t it.

Bob boder
March 7, 2022 7:59 am

This is what happens when the real world comes to call

March 7, 2022 8:05 am

that’s not the right explanation : the temperature is strongly impacted by AMO cycles which include solar cycles and the temperature should drop a little bit ( 0.3 °C ) soon as we entered in a new AMO cycle and a new solar cycle . Also , look at NCDC-NOAA values since 1880, after 1944, last peak at the end of former AMO cycle . AGGI , the index of greenhouse gaz shows 0.6° per century and will continue probably until 2100 …
Together , AMO+AGGI gives a quite good indicator of current temperature :

March 7, 2022 8:20 am

The paper is marred by the usual shenanigans. For starters, it is said that the aa index is downloaded from but that site times out. Both Lockwood and I have shown that aa is too low before 1957. This introduces a strong, artificial upwards trend [to better match any temperature trend]. Then the paper invokes unproven [and unlikely] dependence on influence on solar activity by planets.
Not much credence can thus be placed in their conclusion.

March 7, 2022 8:20 am

Well someone needs the give Berkeley Earth, NOAA, and various others a clue since all their adjustments to the temperature record are aimed at showing a direct correlation of rising temperature to a rising CO2 level.

March 7, 2022 8:40 am

I suggest they apply their technic just to atmospheric water vapor, excluding CO2. I expect them to get a better correlation. We live in a water world and atmospheric water cycles not only control SST’s but also atmospheric concentrations of CO2.

March 7, 2022 8:49 am

We are still thawing out from the Little Ice Age.

Bruce Cobb
March 7, 2022 10:35 am

Ah yes, take the average of an imaginary plus a real forcing. That always works.

March 7, 2022 11:36 am

I think I could have predicted that the temperature might go up or it might go down.

March 7, 2022 4:09 pm

Just goes to show no one has nay idea what the climate change will be, even 25 years into the future let alone 100 years!

March 7, 2022 6:38 pm

The image that heads this attracted my attention – I’m always on the look out for signs of surface pollution by oil/surfactant/lipid. It’s there, but not a very clear example. Water smoothed by such warms – reduced albedo, reduced evaporation etc.

The most amusing example I’ve found is of Broad Lake in the grounds of the University of East Anglia, birthplace of the climate panic. It would be wonderful to discover that some non-CO2 AGW causes are right there on their doorstep.

Catastrophic warming on the Sea of Marmara may be related.

Dennis G. Sandberg
March 7, 2022 10:04 pm

Starting to sound like the science really is settled. CO2 is not an imminent existential catastrophic anthropogenic threat. Let’s move on.

March 8, 2022 10:20 am

This paper appears to be deficient: “Feldman et al. [40] published results from two clear-sky surface radiative forcing measurements with the Atmospheric Emitted Radiance Interferometer (AERI) between 2000 and 2010, when the CO2 concentration increased (according to their estimate) by 22 ppm. They observed an increase of 0.2 W/m2 during this decade, which amounts to 2.4 W/m2 (per 2× CO2). With the usual zero-feedback sensitivity parameter of 0.27 K/(W/m2), this would translate into 0.65 K (per 2× CO2). If we were to use the modified value of 0.31 K/(W/m2) (which allows for variations with latitude [75]), we would obtain 0.75 K.”

It looks like this is what he’s doing. The 0.27 K/Wm-2 figure appears to be a typical CO2-only (no feedback) sensitivity number. That is, doubling CO2 causes 3.71 Wm-2 in radiative forcing and 1 K warming so 1/3.71 = 0.27 K/Wm-2. So he assumes 3.71 Wm-2 for 2xCO2 and 1 Kwarming for 2xCO2. Then in his calculation he says Feldman’s observations amounted to an 2.4 Wm-2 for 2xCO2. From this he calculates CO2-only sensitivity to be 0.27*2.4 = 0.65 C. But he uses two different values for the RF for 2xCO2. If he had used 2.4 Wm-2 in both places, he of course would just end up right back where he started – 1/2.4 = 0.42 K/Wm-2 (not 0.27) and 0.42*2.4 = 1 K. So he “calculated” a low CO2 sensitivity by switching his 2xCO2 radiative forcing value, and he assumed CO2-only sensitivity of 1 K to calculate it to be 0.65 K. The math works out the same for what he says about Rentch. He takes 2.63 Wm-2 (for 2xCO2) and “calculates” 2.63*0.27 to get 0.71 K. He’s assuming CO2-sensitivity of 1 K for 3.71 Wm-2 to calculate it to be 0.71 K. It appears he doesn’t know where his 0.27 K/Wm-2 figure comes from or what it means.

Last edited 2 months ago by Scott Simmons
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