Read here. New research published today by Andy Dessler, an IPCC Climategate scientist, appears to have major shortcomings. His new study was greased, like goose leavings, through the peer reviewed process in just a few weeks, which may have contributed to the work's shoddiness.
Supposedly, Dessler's new research was to be a refutation of the Spencer and Braswell 2011 study that revealed clouds were likely to be a negative climate feedback. Instead of doing an apple-to-apple comparison though, Dessler chose a different temperature dataset (a non-consensus dataset avoided by the IPCC) than the Spencer research.
Unfortunately, the choice of non-HadCRUT, non-IPCC dataset, reflects the unbridled cherry-picking temptation that the Dessler research fell victim to. If the HadCRUT dataset is the IPCC benchmark that Spencer research followed, then Dessler should have met the scientific challenge by using the same best-of-breed data that the IPCC demands.
It now seems obvious that Dessler knew his research would falter if based on the gold-standard of the IPCC. If this wasn't the case, why not use the gold-standard?
Even with his cherry-picking of the dataset, Dessler research does not hold up to the statistical scrutiny that Steve McIntyre brings to the table. It didn't take long for Steve to ascertain that the positive cloud feedback that Dessler claims might not be so "positive."
"Doing the same regression with 4-month lagged relationships (which both Dessler and SB agree to be more significant than the instantaneous relationship), the sign of the slope is reversed. Whereas Dessler 2010 had reported a slope of 0.54 +- 0.72 (2σ) W/m2/K, the regression with lagged variables is -0.90 +- 0.95 w/m2/K and has better diagnostics...Given that the even the lagged relationship is weak, I’m reluctant to say that analysis using the methods of Dessler 2010 established a negative feedback, but it does seem to me that they cannot be said to have established the claimed positive feedback...Perhaps the editor of Science will send a written apology to Kevin Trenberth."
Objectively, if the Dessler rushed peer reviewed research is the best that mainstream climate scientists can deliver against the Spencer and Braswell study, then it's a case closed. Clouds do appear to be a negative feedback mechanism within the climate system as the Spencer 2011 work suggests.
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