Hermann Harde
Great news!! Professor Hermann Harde who is a German academic who specialises in gas absorption and thoroughly understands the radiative properties of gases, has used the very latest up to date HITRAN database of gas absorption spectra and discovered that the IPCC have overstated the effect of CO2 by some 30%
“Simulations of the up- and down-welling radiation and its interaction with the most prominent greenhouse gases water vapour, carbon dioxide, methane, and ozone in the atmosphere are presented. The radiative forcing at doubled CO2 concentration is found to be 30% smaller than the IPCC-value.” (Radiation and Heat Transfer in the Atmosphere: A Comprehensive Approach on a Molecular Basis)
Having corresponded with Prof Harde before when the paper was in German, I already knew that his work with the HITRAN 2008 database produced startling different results from the IPCC figures which use earlier versions of the HITRAN database. The big difference is simple: the latest database has more details and allows a more detailed comparison of the effects of gases in the atmosphere.
The simplest way to explain this is to tell you the story of our escaping chickens. We have a chicken run outside. We obtained another batch of chicks from ebay and put them in the run. An hour later they had all escaped. We put them back, blocked checked every possible exit and … and hour later they escaped again. It was not until we saw one escaping that we realised that the mesh that held the big chickens in was too course for the smaller chickens.
This appears to be the problem with earlier HITRAN databases. Each data “bucket” for radiative absorption is for a wider range of frequencies than the HITRAN 2008 database. The result is that there are fine holes which in effect “let the radiation out”.
The result is that the greenhouse effect of CO2 has been overestimated by 30%.
Great news! Well No!!
The problem is that the greenhouse effect has no impact WHAT-SO-EVER on the climate predictions. Because all the modellers do is scale up this effect by whatever they want to make their predictions hindcast the past. So, all this paper can do is cause the modellers to increase their presumed (and false) relationship between CO2 and global temperature and as the 30% decrease in the CO2 greenhouse effect will be exactly matched by a 30% increase in the scaling factor in the models, the result will be EXACTLY THE SAME PREDICTIONS!!
You might find http://rabett.blogspot.co.uk/2011/03/toy-model.html interesting.
Can you show me anyone else who has used the latest HITRAN database?
Why not? Because the latest database has finer features which produce a lower figure for the greenhouse effect of CO2.
But why are we bothering even discussing this because no matter what anyone finds the CO2 greenhouse to be, it has absolutely no effect on the IPCC predictions.
Well, of course, we now have HITRAN 2012
http://www.cfa.harvard.edu/hitran/
which all of the serious radiation modeling groups use. You can even use 2008 on line for $50/month from spectralcalc to do what Harde did
http://www.spectralcalc.com/spectral_browser/db_intensity.php
But more seriously, if you look at his 2013 paper he is still screwing around with water vapour concentrations to get his results.
in a normal greenhouse is a solid glass roof. CO2 is only trace gas in the atmosphere = roof as a postage stamp – the rest of 998999ppm is oxygen & nitrogen – they are regulating the cooling. CO2 not guilty
From which the rational conclude that the Greenhouse effect works a bit differently than the greenhouses protecting your tomatoes. Also, just about anything from the Science of Doom
Eli, any ”rational” would say that: ”the name ”Greenhouse” is misleading 100%!!!”
Greenhouse gas deniers. The rapid warming is due to the atmospheres inability to radiate all the incoming energy back into space
If you read the article and the linked to paper, you will find that Hermann Harde is an expert in the effects of CO2 and has used the same methodology as the IPCC to work out the effect of CO2, but the only significant difference is that he has used the up-to-date HITRAN database which indicates around 30% less warming.
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