An important paper

Real Climate has an important post up about a paper by Dessler out this week on clouds and climate sensitivity.   The actual paper can be read here.

Basically, it analyses satellite data and suggests that increased clouds will not protect the earth from increasing temperatures, as Spencer and Lindzen have argued.  Roy Spencer also had a paper analysing satellite data out recently; until now, response to it had been strangely quiet.

Dessler does acknowledge that it will be a long time before precise long term cloud feedback is pinned down with certainty.   But the post in Real Climate is  well worth reading because it seems to put Spencer’s opinion in its eccentric context:

After reading this, I initiated a cordial and useful exchange of e-mails with Dr. Spencer (you can read the full e-mail exchange here). We ultimately agreed that the fundamental disagreement between us is over what causes ENSO. Short paraphrase:

Spencer: ENSO is caused by clouds. You cannot infer the response of clouds to surface temperature in such a situation.

Dessler: ENSO is not caused by clouds, but is driven by internal dynamics of the ocean-atmosphere system. Clouds may amplify the warming, and that’s the cloud feedback I’m trying to measure.

My position is the mainstream one, backed up by decades of research. This mainstream theory is quite successful at simulating almost all of the aspects of ENSO.

Dr. Spencer, on the other hand, is as far out of the mainstream when it comes to ENSO as he is when it comes to climate change. He is advancing here a completely new and untested theory of ENSO — based on just one figure in one of his papers (and, as I told him in one of our e-mails, there are other interpretations of those data that do not agree with his interpretation).

Thus, the burden of proof is Dr. Spencer to show that his theory of causality during ENSO is correct. He is, at present, far from meeting that burden. And until Dr. Spencer satisfies this burden, I don’t think anyone can take his criticisms seriously.

It’s also worth noting that the picture I’m painting of our disagreement (and backed up by the e-mail exchange linked above) is quite different from the picture provided by Dr. Spencer on his blog. His blog is full of conspiracies and purposeful suppression of the truth. In particular, he accuses me of ignoring his work. But as you can see, I have not ignored it — I have dismissed it because I think it has no merit. That’s quite different.