Paul Ostergaard writes via email:
Here is an interesting new paper that Miklos Zagoni has pointed me to via Judith Curry’s blog. This researcher in Germany has carried out a spectroscopic analysis of the impact of CO2 and other greenhouse gases’ contribution to warming.
It arrives (surprise!) at a value one seventh of the IPCC best estimate for Climate Sensitivity for a CO2 doubling. Looks intriguing at first blush…
The climate sensitivity CS as a measure for the temperature increase found, when the actual CO2-concentration is doubled, assumesCS = 0.41 ̊C for the tropical zone, CS = 0.40 ̊C for the moderate zones and CS = 0.92 ̊C for the polar zones. The weighted average over all regions as the global climate sensitivity is found to be CS = 0.45 ̊C with an estimated uncertainty of 30%, which mostly results from the lack of more precise data for the convection between the ground and atmosphere as well as the atmospheric backscattering…. The values for the global climate sensitivity published by the IPCC [3] cover a range from 2.1 ̊C – 4.4 ̊C with an average value of 3.2 ̊C, which is seven times larger than that predicted here.
Here is the link to the abstract:
http://meetingorganizer.copernicus.org/EGU2011/EGU2011-4505-1.pdf
The paper is being presented at the EGU General Assembly 2011 in Vienna.
Perhaps our WUWT readers can dissect this and see how well it holds up. It is important to verify if the paper’s methodology is sound.
===============================================================
How much CO2 really contributes to global warming? Spectroscopic
studies and modelling of the influence of H2O, CO2 and CH4 on our
climate
Hermann Harde
Helmut-Schmidt-Universität Hamburg, Germany
Based on the actual HITRAN’2008 database [1] detailed spectroscopic studies on the absorbance of the greenhouse gases water, carbon dioxide and methane in the atmosphere are presented. The objective of these investigations was to examine and to quantify with these newly available data the influence of these gases on our climate.
The line-by-line calculations for sun light from 0.1 – 8 m (short wavelength radiation) as well as those for the emitted earth radiation from 3 – 60 m (long wavelength radiation) show, that due to the strong overlap of the CO2 and CH4 spectra with the water vapour lines the influence of these gases is significantly reducing with increasing water vapour pressure, and that with increasing CO2-concentration well noticeable saturation effects are observed limiting substantially the impact of CO2 on the warm-up of the atmosphere.
For the water vapour, which in its concentration is considerably varying with the altitude above ground as well as with the climate zone, separate distributions for the tropes, the moderate zones and the polar regions are presented.
They are based on actual GPS-measurements of the water content in these zones [2] and are applied for calculating the absorbance in the respective regions. The vertical variation in humidity and temperature, in the partial gas pressures and the total pressure is considered for each zone separately by computing individual absorption spectra for up to 228 atmospheric layers from ground level up to 86 km height.
The propagation length of the sun light in these layers, which depends on the angle of incidence to the atmosphere and therefore on the geographic latitude, is included by considering the earth as a truncated icosahedron (bucky ball) consisting of 32 surfaces with well defined angles to the incoming radiation and assigning each of the areas to one of the three climate zones.
To identify the influence of the absorbing gases on the climate and particularly the effect of an increasing CO2- concentration on the warming of the earth, a two-layer climate model was developed, which describes the atmosphere and the ground as two layers acting simultaneously as absorbers and Planck radiators. Also heat transfer by convection between these layers and horizontally by winds or oceanic currents between the climate zones is considered.
At equilibrium each, the atmosphere as well as the ground, delivers as much power as it sucks up from the sun and the neighbouring layer or climate zone.With this model for each climate zone the temperature progression of the earth and the atmosphere is calculated as a function of the CO2-concentration and several other parameters like ozone and cloud absorption, short- and long-wavelength scattering at clouds as well as the reflection at the earth’s surface.
The simulations for the terrestrial and atmospheric warm-up show well attenuating and saturating progressions with increasing CO2-concentration, mainly caused by the strongly saturating absorption of the intensive CO2 bands and the interference with water lines. The climate sensitivity CS as a measure for the temperature increase found, when the actual CO2-concentration is doubled, assumesCS = 0.41°C for the tropical zone, CS = 0.40°C for the moderate zones and CS = 0.92°C for the polar zones. The weighted average over all regions as the global climate sensitivity is found to be CS = 0.45°C with an estimated uncertainty of 30%, which mostly results from the lack of more precise data for the convection between the ground and atmosphere as well as the atmospheric backscattering.
The values for the global climate sensitivity published by the IPCC [3] cover a range from 2.1°C – 4.4°C with an average value of 3.2°C, which is seven times larger than that predicted here.
studies and modelling of the influence of H2O, CO2 and CH4 on our
climate
Hermann Harde
Helmut-Schmidt-Universität Hamburg, Germany (harde@hsu-hh.de)
Based on the actual HITRAN’2008 database [1] detailed spectroscopic studies on the absorbance of the greenhouse
gases water, carbon dioxide and methane in the atmosphere are presented. The objective of these investigations
was to examine and to quantify with these newly available data the influence of these gases on our climate.
The line-by-line calculations for sun light from 0.1 – 8 m (short wavelength radiation) as well as those for the
emitted earth radiation from 3 – 60 m (long wavelength radiation) show, that due to the strong overlap of the CO2
and CH4 spectra with the water vapour lines the influence of these gases is significantly reducing with increasing
water vapour pressure, and that with increasing CO2-concentration well noticeable saturation effects are observed
limiting substantially the impact of CO2 on the warm-up of the atmosphere.
For the water vapour, which in its concentration is considerably varying with the altitude above ground as well as
with the climate zone, separate distributions for the tropes, the moderate zones and the polar regions are presented.
They are based on actual GPS-measurements of the water content in these zones [2] and are applied for calculating
the absorbance in the respective regions. The vertical variation in humidity and temperature, in the partial gas
pressures and the total pressure is considered for each zone separately by computing individual absorption spectra
for up to 228 atmospheric layers from ground level up to 86 km height.
The propagation length of the sun light in these layers, which depends on the angle of incidence to the atmosphere
and therefore on the geographic latitude, is included by considering the earth as a truncated icosahedron (bucky
ball) consisting of 32 surfaces with well defined angles to the incoming radiation and assigning each of the areas
to one of the three climate zones.
To identify the influence of the absorbing gases on the climate and particularly the effect of an increasing CO2-
concentration on the warming of the earth, a two-layer climate model was developed, which describes the atmosphere
and the ground as two layers acting simultaneously as absorbers and Planck radiators. Also heat transfer by
convection between these layers and horizontally by winds or oceanic currents between the climate zones is considered.
At equilibrium each, the atmosphere as well as the ground, delivers as much power as it sucks up from the
sun and the neighbouring layer or climate zone.With this model for each climate zone the temperature progression
of the earth and the atmosphere is calculated as a function of the CO2-concentration and several other parameters
like ozone and cloud absorption, short- and long-wavelength scattering at clouds as well as the reflection at the
earth’s surface.
The simulations for the terrestrial and atmospheric warm-up show well attenuating and saturating progressions with
increasing CO2-concentration, mainly caused by the strongly saturating absorption of the intensive CO2 bands and
the interference with water lines. The climate sensitivity CS as a measure for the temperature increase found, when
the actual CO2-concentration is doubled, assumesCS = 0.41°C for the tropical zone, CS = 0.40°C for the moderate
zones and CS = 0.92°C for the polar zones. The weighted average over all regions as the global climate sensitivity
is found to be CS = 0.45°C with an estimated uncertainty of 30%, which mostly results from the lack of more
precise data for the convection between the ground and atmosphere as well as the atmospheric backscattering.
The values for the global climate sensitivity published by the IPCC [3] cover a range from 2.1°C – 4.4°C with an
average value of 3.2°C, which is seven times larger than that predicted here.
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Based on an equitorial circumference of 24,901.55 mi the difference in the surface area of a sphere of said circumference and an icosidodecahedron of 32 faces (not truncated) whose edge “a” is 1/10 of the equitorial circumference is a hair over 7.9%. Close enough for “government work”, I’m sure!
John_in_Oz says:
March 3, 2011 at 8:43 am
Extremely well said! Bravo!, Sir. (Paraphrasing Orwell again: In these times, it is a duty to point out the obvious – well, what should be obvious.)
The paper suffers from the many problems that you identified. What I find intriguing in the paper is that it “combines” the GHGs and attempts to calculate their impact on one another. If such calculations prove to be important then they show the folly of treating CO2 as randomly distributed throughout the atmosphere. Why? Because water vapor is far from randomly distributed and if the calculations require the combined GHGs then the values for CO2 will vary between those areas where there is no water vapor and those waters where water vapor is found. See, the values for CO2’s effects on the climate are not randomly distributed throughout the atmosphere.
Zagoni’s 0.47 is certainly closer to the 0.10 that the IPCC should have predicted if they had not unilaterally multiplied the effect 12-fold to produce 1.2 before adding their positive forcing factor, water vapor.
If course, it should be asked about the effects any heating would have on the convectional circulations and this negative feedback heat engine.
If I remember right, Roy Spencer came up with one climate sensitivity number of about 0.6 C per CO2 doubling and Richard Lindzen came up with about 0.5C. So this is right in that ballpark.
Well, we already know the IPCC is nonsense. Any good study can only take us in one direction from there.
This article is very interesting, however even if it is completely accurate it will not be a show stopper for the global warming crowd.
Has anyone placed a series of very intense light sources (visible through IR) on the surface of the earth and aimed them at a satellite equipped with a detector capable of measuring absorbance in the near IR and IR range? I realize the light would be significantly reduced in intensity when it reached the satellite, however if you used non-absorbing wavelengths as a reference, perhaps you could directly measure the additional absorbance due to carbon dioxide and methane in the presence of the entire atmosphere.
Perhaps you could develop a real model of the effect of carbon dioxide using multivariate analysis of a host of variables, such as
1. location on earth
2. altitude
3. season of measurement (and hence level of carbon dioxide)
4. temperature
5. humidity and cloud cover
6. levels of airborne particles and other pollutants
Perhaps what I suggest won’t work, however I simply do not know why we don’t get better data and fast since the EPA is now itching to regulate emissions of carbon dioxide and cause major disruptions to our economy.
The 32 faces of the truncated icosahedron seems like a soccer ball. It is not a sphere, but the error from that approximation is probably smaller than any other factor involved in the calculation.
Arnold Ramsland says: March 3, 2011 at 8:12 pm
“This article is very interesting, however even if it is completely accurate it will not be a show stopper for the global warming crowd. ”
Arnold, having examined the background of this scientist and worked out the way he has come at this problem through his expertise in the radiative absorption of trace gases in the atmosphere, and the fact this is new research stemming from an improved modelling technique for trace gases which has been proven in other areas and then applied to modelling the atmosphere. (see: http://scottishsceptic.wordpress.com/2011/03/03/how-much-co2-really-contributes-to-gw-further-analysis for details)
Well, how do I put this? Climategate undermined the scientific credibility of the people, but not the fundamental science, this has undermined not only the fundamental science, but as a result the financial credibility of investments in renewable energy and carbon trading. A few sharp people are going to make an awful lot of money out of this!
Scottish Sceptic says:
March 4, 2011 at 12:55 am
Am I understanding this correctly – the model removes the requirement for “forcings” and “feedbacks” because it calculates them internally? (accepting, for the moment, your question about clouds). And that the spectroscopy is being refined and updated against experimental data? If this is indeed the case this could be a “whole new ball game”.
While many questions remain (eg. clouds, element size, rotating planet, etc.) It would be very interesting to see this paper submitted for peer review (hopefully not by the usual suspects!) with all of the data and codes necessary for other researchers to attempt to verify or falsify the methodology. If the initial conclusions can be independently replicated and verified we would have a situation where this (seemingly much more scientific) model directly contradicts the models that have been the sole “evidence” relied upon by the CAGW industry.
Interesting times indeed!
Roger Longstaff says: March 4, 2011 at 4:09 am
“While many questions remain (eg. clouds, element size, rotating planet, etc.) It would be very interesting to see this paper submitted for peer review (hopefully not by the usual suspects!) with all of the data and codes necessary for other researchers to attempt to verify or falsify the methodology. If the initial conclusions can be independently replicated and verified we would have a situation where this (seemingly much more scientific) model directly contradicts the models that have been the sole “evidence” relied upon by the CAGW industry.
Interesting times indeed!”
As you say, very interesting!!! At the very least this person knows his stuff about radiative transmission and absorption of trace gases in the atmosphere, and so I’d say it is about 90% certain that the accepted level of direct CO2 heating will come down as a result. And, although not explicitly stated in the paper, it would also appear that the scale of the feedback mechanisms will also have to be reduced.
That’s irrespective of whether his global atmospheric model holds up!!!!. But given his skill in modelling using the HITRAN database of the atmosphere, I’m not expecting to get major problems in the direct radiative heating and IR blocking.
Where I do think he may be struggling is in characterising the atmosphere, particularly dynamic aspect like air movement. Like him, I’m not very familiar with atmospheric models in this area, but from what little I know, it does appear most models assume a static atmosphere and probably use the same database of gas and H2O concentrations.
So, assuming he has used a well known and accepted source for atmospheric gas levels, and dynamic effects are either small or well modelled, and that he hasn’t made any gross errors in his model. About the only criticism to be levelled is his apparent comparison of his direct warming with the IPCC direct + indirect … for which he will no doubt be slaughtered, but I don’t think it will fundamentally undermine his work outside the climategate community.
The only worrying thing that comes to mind, is that it all seems too good to be true! Could it all be some kind of “set up”? A little known academic publishes an earth shattering paper … widely acclaimed by the sceptics … only to publish a correction making it very much in line with the “consensus” … and though it might seem far fetched, with the huge stock market values and personal reputations riding on this whole thing, who knows?
Interesting times … but I can’t wait to see the details, nor if it holds water to watch the reaction of the warmers!
A seven-fold difference in the predicted values for the impact of carbon dioxide leads me to question both the IPCC model and the new model. Hopefully, the Scottish Sceptic is correct in his analysis, however I think a thorough comparison of the two models is called for in order to find out the source of the discrepancies. After finding the discrepancies, actual experimental studies should be carried out in order to find out which data or which assumptions are more accurate.
Are the IPCC data and models available for review?
Scottish Sceptic says:
March 4, 2011 at 6:20 am: “…it all seems too good to be true!”
Perhaps, but this is all based upon HITRAN database of the atmosphere. If this is a scientifically robust model, tested against reality, then at least the foundation of the methodology must be correct. A very brief search of the web indicates that HITRAN is not a hoax – or have I missed something?
Roger Longstaff says: March 4, 2011 at 7:08 am
Scottish Sceptic says: “…it all seems too good to be true!”
A very brief search of the web indicates that HITRAN is not a hoax – or have I missed something?
You haven’t missed anything.
All I’m saying is that there is an awful lot of money riding on convincing the public of global warming. There’s no doubt that many people with an expertise in psychology/psychiatry have been consulted (they even ran a seminar specifically on this subject). What kinds of strategies would an imaginative group of such people come up with?
One possible scenario is to fabricate a result that we trumpet to the public as “disproving global warming” and then they spring the trap and the author “corrects” their paper to fit the established status quo, leaving the sceptics appearing to support the status quo or looking like a right load of twats.
We just know too little at the moment to be anything other than sceptical (although I must admit I had a celebration whisky last night!)
I think the saying is “beware Greeks bearing gifts” … for footballers I think the saying is: “beware sheiks “(… working for newspapers). Likewise, we should beware “Germans bearing papers” particularly when they appear to be a gift to the sceptics, and we really know very little about the source of that gift.
Ahah!
Now we’ve got them!
A badly translated and totally cryptic abstract for a poster session at an EGU meeting, if read in a certain way, absolutely CRUSHES everything the warmist have been writing in peer reviewed lit for decades! (And poster sessions is where the beer is, and it’s German beer! So you know it’s good.)
Paulie Two-o-one says: March 5, 2011 at 6:13 am
“Ahah! Now we’ve got them!
A badly translated and totally cryptic abstract for a poster session at an EGU meeting, if read in a certain way, absolutely CRUSHES everything the warmist have been writing in peer reviewed lit for decades! “
But if like me you have just translated the full 50 page paper and can actually see that goes into considerable depth and so far it seems to be everything it said on the lid!