Anthony Watts at Watts Up with That links a new paper by Lindzen and Choi, upcoming in the Asia-Pacific Journal of Atmospheric Sciences. I haven’t read the full paper yet, but based on the abstract and conclusions, what they’re reporting is that, basically, the climate models used by the IPCC — and thereby used by Gore in An Inconvenient Truth, and by the EPA in pushing CO2 regulation — overstate the effect on global average surface temperature of increased CO2 in the atmosphere. This paper is a re-evaluation of their 2009 results in response to criticisms.
The paper appears to have two important points: first, based on observational data (as opposed to modeling), the amount of GAST increase based on the observed increase in CO2 is between 0.5C and 1.3C, where the models show between 1.5C and 5C; second, that the temperature feedback is negative, or in other words, increasing CO2 concentration has decreasing effect on GAST, where the IPCC models show positive feedback.
I expect momentarily a press release from Real Climate decrying Lindzen and Choi as poopyheads.