The starting point: a NASA scientist named Ferenc M. Miskolczi. Way back in 2006, Mr. Miskolczi began to ponder why the climate models were still using methods designed to work around the lack of computer power when modern computers gave them all the power they needed to do it right. This sort of simplification of models is very common when modeling complex natural phenomenon, as the amount of data and computation can easily completely overwhelm any computer.
But the climate models then (and still today!) used some simplifications that were, to put it mildly, suspect. Mr. Miskolczi focused on one particular such simplification: the models' assumption that the Earth's atmosphere had an infinite “optical thickness”, which basically is an assumption that the optical characteristics of the atmosphere are the same at every altitude. In fact, the Earth's atmosphere grows less dense with altitude (an approximately exponential decline), and by the time you reach 100 km (about 60 miles) in altitude there is almost no atmosphere at all – and the optical characteristics of the atmosphere change accordingly. It isn't constant at all. Mr. Miskolczi wondered what effect on the models would be obtained by replacing that simplification with reality – something modern computers are fully capable of doing.
The results were very interesting, to say the least. Keep in mind that Mr. Miskolczi's changes are still a model, not empirical evidence. All he did was to remove a simplification to make the existing models adhere more closely to reality. But when he did that, poof! Global warming disappeared, just like that. I just made a huge simplification of his study, but that's the essence of it in layman's language.
Of course with such startling and important results, Mr. Miskolczi immediately tried to publish his study. NASA (whose chief climatology scientist is James Hanson, whom I've posted about several times) refused. After finally giving up on getting his work published through his employer, Mr. Miskolczi resigned in protest – and published his study independently. You can read the whole thing here. Here's the abstract:
In this work the theoretical relationship between the clear-sky outgoing infrared radiation and the surface upward radiative flux is explored by using a realistic finite semi-transparent atmospheric model. We show that the fundamental relationship between the optical depth and source function contains real boundary condition parameters. We also show that the radiative equilibrium is controlled by a special atmospheric transfer function and requires the continuity of the temperature at the ground surface. The long standing misinterpretation of the classic semi-infinite Eddington solution has been resolved. Compared to the semi-infinite model the finite semi-transparent model predicts much smaller ground surface temperature and a larger surface air temperature. The new equation proves that the classic solution significantly overestimates the sensitivity of greenhouse forcing to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular planetary average flux optical depth of 1.841 . Simulation results show that the Earth maintains a controlled greenhouse effect with a global average optical depth kept close to this critical value. The broadband radiative transfer in the clear Martian atmosphere follows different principle resulting in different analytical relationships among the fluxes. Applying the virial theorem to the radiative balance equation we present a coherent picture of the planetary greenhouse effect.And here's a snippet from a representative page:
Here's some further reading on the above story (and its principals): here, here, here, here, and here.
On a related note, the lamestream media appears to be picking up on the idea that perhaps the fact that millions upon millions of dollars of research grants are at stake has something to do with the motivation of global warming proponents. Ya think? The preceding link is to a New York Times article whose author seems to be a bit bemused that global warming proponents would accuse the skeptics of being motivated by the money … as well he should be!
The past couple of months has seen more positive portrayal of global warming (anthropogenic or not) skeptics in the media than I've seen since the Goracle started his agitprop. I hope this will lead to some balance in the research funding, and (consequently) in the quality of the science emerging from it...