Saturday, November 26, 2011

2004 email from Richard Somerville: "We don't understand cloud feedbacks. We don't understand air-sea interactions. We don't understand aerosol indirect effects. The list is long"

Email 1107, circulated among prominent warmists

Many of us were pleasantly surprised that our leading scientific societies have recently adopted such strong statements as to the reality and seriousness of anthropogenic climate change. There really is a scientific consensus, and it cannot be refuted or disproved by attacking any single data set.

I also think people need to come to understand that the scientific uncertainties work both ways. We don't understand cloud feedbacks. We don't understand air-sea interactions. We don't understand aerosol indirect effects. The list is long. Singer will say that uncertainties like these mean models lack veracity and can safely be ignored. What seems highly unlikely to me is that each of these uncertainties is going to make the climate system more robust against change. It is just as likely a priori that a poorly understood bit of physics might be a positive as a negative feedback.

1 comment:

Doubting Richard said...

Wow. This guy doesn't even have the most basic idea of feedback. Nor does he understand how science works, haw to judge confidence in an hypothesis. "[S]eems highly unlikely to me" is not really a recognised statistical technique to assert a very major claim.

Net positive feedback is not only rare in natural systems but unheard of in a system with static stability or showing equilibrium (Le Chatelier's principle states this for chemistry, but it is far more general). So either the temperature is statically unstable, in which case current warming is unlikely to be unprecedented, or it is statically stable in which case there is no net positive feedback (and almost certainly net negative feedback).

The only other option is in my opinion the most likely to be correct. global mean temperature is a meaningless artifice. The world has dozens of interdependent climates, which respond to their own forcings and feedbacks, some of which come from other climate systems.