Congratulations to Dr’s Roy Spencer and William Braswell, who have finally managed to get their paper on radiative forcing and uncertainty in diagnosing climate sensitivity published in the Journal of Geophysical Research.
Spencer, R. W., and W. D. Braswell (2010), On the diagnosis of radiative feedback in the presence of unknown radiative forcing, J. Geophys. Res., 115, D16109, doi:10.1029/2009JD013371.
You can get your free copy from Dr Roy’s site here: http://www.drroyspencer.com/wp-content/uploads/Spencer-Braswell-JGR-2010.pdf
I recommend a visit to Dr Roy’s website, where his posts are becoming increasingly frank, and highly entertaining. 🙂
Then, once you think you understand the main points we make in the new JGR paper, read any other critiques or criticisms that catch your fancy.
As a teaser, one of the clear conclusions the new paper supports is this: The only times that there is clear evidence of feedback in global satellite data, that feedback is strongly negative.
All I ask is that you evaluate whether anyone can come up with a better explanation than what we have given for the structures we see in the satellite observations of natural climate variations. Do not settle for others’ vague arm-waving dismissals based upon preconceived notions or what others have told them.
You engineers and scientists from other fields are capable of understanding this, and I am appealing to you to bring fresh eyes to a field where the research establishment has become hopelessly inbred and too beholden to special interests to see that which is staring them in the face.
This is the main reason why I wrote The Great Global Warming Blunder…the evidence is simple enough for the science-savvy public to understand. But the experts do not see the evidence because they refuse to open their eyes…
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As we show in the new paper, the only clear signal of feedback we ever find in the global average satellite data is strongly negative, around 6 Watts per sq. meter per degree C. If this was the feedback operating on the long-term warming from increasing CO2, it would result in only 0.6 deg. C of warming from 2XCO2. (Since we have already experienced this level of warming, it raises the issue of whether some portion — maybe even a majority — of past warming is from natural, rather than anthropogenic, causes.)
Unfortunately, there is no way I have found to demonstrate that this strongly negative feedback is actually occurring on the long time scales involved in anthropogenic global warming. At this point, I think that belief in the high climate sensitivity (positive feedbacks) in the current crop of climate models is a matter of faith, not unbiased science. The models are infinitely adjustable, and modelers stop adjusting when they get model behavior that reinforces their pre-conceived notions.
They aren’t necessarily wrong — just not very thorough in terms of exploring alternative hypotheses. Or maybe they have explored those, and just don’t want to show the rest of the world the results.
Way to go Roy, tell ’em like it is, you’ve earned your place in the Hall of Fame.
Tallbloke's Talkshop 
Roger, thanks for linking this paper. I have been following the moves towards publication on Roy S’s site. The more widely disseminated this study can be made the better, because the feedback issue is so central to the validity of much of the climate modeling that is currently quoted as gospel by AGW proponents.
Hi Roy. Yes, it’s important, but as Roy points out on his blog, the gatekeepers forced him to rephrase in bland terms. This reduces the paper’s impact, and shows the double standards of the reviewers, who have allowed much unsupported alarmist nonsense through. I think it needs someone who thoroughly understands it to write a ‘laymans’ version to help get the message over.
As Roy Spencer says:
“Entitled “On the Diagnosis of Feedback in the Presence of Unknown Radiative Forcing“, this paper puts meat on the central claim of my most recent book: that climate researchers have mixed up cause and effect when observing cloud and temperature changes. As a result, the climate system has given the illusion of positive cloud feedback.
Positive cloud feedback amplifies global warming in all the climate models now used by the IPCC to forecast global warming. But if cloud feedback is sufficiently negative, then manmade global warming becomes a non-issue.
While the paper does not actually use the words “cause” or “effect”, this accurately describes the basic issue, and is how I talk about the issue in the book. I wrote the book because I found that non-specialists understood cause-versus-effect better than the climate experts did! “