I’m Happy To Help, Judith Curry: Overconfidence In IPCC’s Detection And Attribution

http://wmbriggs.com/blog/?p=3074 ^ | William M. Briggs

[mattstat]

Thanks to reader Roger Cohen for brining this to my attention.

Atmospheric scientist Judith Curry recently ran a series of blog posts entitled, “Overconfidence in IPCC’s detection and attribution.” In Part III of that series, she set out a public appeal:

I am no expert in logic. My only formal exposure was a course in freshman logic nearly 40 years ago…I can understand most Bayesian arguments that I’ve encountered, although I’ve never attempted to make one on my own…My point is that I think there are some glaring logical errors in the IPCC’s detection and attribution argument, that it doesn’t take an expert in logic to identify. I look forward to the input from logicians, bayesians, and lawyers in terms of assessing the IPCC’s argument.

I flatter myself that I am an expert in the matter of how evidence supports belief; further, I am happy to offer my assistance. Let me first answer a potential criticism that others might use after reading your appeal. It is possible to argue that when the term “Bayesian” is used, it is synonymous with “better”, especially in statistical analysis contexts. But “Bayesian” is not synonymous with “good results” or “correct modeling.” In other words, following a Bayesian procedure does not guarantee validity. Thus, even though you in your criticism of the IPCC, and the IPCC in its self assessments, use Bayesian procedures, both of you can be wrong in your conclusions. I’m guessing you knew that....

[dajeeps]

“It is error alone which needs the support of government. Truth can stand by itself. Subject opinion to coercion: whom will you make your inquisitors? Fallible men; men governed by bad passions, by private as well as public reasons. And why subject it to coercion? To produce uniformity. But is uniformity of opinion desireable? No more than of face and stature. Introduce the bed of Procrustes then, and as there is danger that the large men may beat the small, make us all of a size, by lopping the former and stretching the latter. “

-Thomas Jefferson

[palmer]

Thermodynamics says there will ultimately be a new equilibrium from increased heat absorbing gases (which come from physics). This might be 1 degree or so for a doubling of CO2. But science cannot say how long it will take to reach equilibrium nor the amount (if any) of added warming from increased H2O. The basic problem with the models is that they lack the resolution to model convection and the distribution of water vapor. Without knowing the distribution of water vapor (even versus uneven), it is impossible to know the amount of water vapor feedback. Observations in the real world suggest that it is negligible, and that weather acts as a damper on warming from other sources.