18 November 2011

A Few Comments on the IPCC SREX Report

The IPCC SREX report came out today and there were no surprises in the report itself.  Here are a few thoughts on the report.

Most importantly, the IPCC should be congratulated for delivering a message that cannot have been comfortable to deliver.  The IPCC has accurately reflected  the scientific literature on the state of attribution with respect to extreme events -- it is not there yet, not even close, for events such as floods, hurricanes, tornadoes, bushfires and on other topics there remain enormous uncertainties.  That is just the way that it is, so that is indeed what the IPCC should have reported.

The IPCC has already been criticized by those who apparently would have preferred a less accurate message that hyped up the science, such as Joe Romm and Stefan Rahmstorf. I do agree with Rahmstorf that the IPCC should release its full report at the same time as it releases the SPM, but he knows as well as I what the literature says on this subject.

More generally, the reaction to the report has fallen out perfectly predictably. Those wanting to hype the report focus exclusively on its predictions of the future whereas those wanting to downplay it focus on the uncertainties. There is something here for everyone!

There was one interesting change related to the statement on the state of attribution with respect to normalized disaster losses.  The draft said:
"Long-term trends in normalized economic disaster losses cannot be reliably attributed to natural or anthropogenic climate change, particularly for cyclones and floods (medium evidence, high agreement)."
The final version took out the emphasis on cyclones and floods and put in a content free clause -- a good example of how the IPCC process can reduce information content:
“Long-term trends in economic disaster losses adjusted for wealth and population increases have not been attributed to climate change, but a role for climate change has not been excluded (medium evidence, high agreement).”
It is of course true that a role for climate change has not been excluded in attribution studies -- of course, the IPCC also did not exclude a role for solar influences, cosmic rays or for that matter, evil leprechauns.  What the draft said with respect to floods and cyclones remains the case, hiding it from view doesn't make it go away. What silliness.

Richard Klein, a colleague and a friend, is also a SREX lead author. He  left a comment at Joe Romm's blog soon after it was posted that  Joe has refused to post so far (as if anyone needed to learn more about how these guys operate):
Dear Joe, you know very well that the IPCC bases its findings on science, not on opinion polls of US Americans. Over the past week, while participating in the IPCC session in Kampala, I've been amazed to read the various opinions of 'experts' who weren't involved in the drafting process or even as a reviewer. While the summary of the report was still being discussed and had not yet been released (this will be done today at 1.30 pm local time in Kampala), these 'experts', either on their own accord or prompted by the media, chose to misrepresent both the report's findings and the process by which the IPCC arrived at these findings.

I have been impressed with the rigour with which my co-authors have assessed the climate science of both observations and projections of extreme weather and climate events. I am also impressed with the solid discussions that took place among governments and between governments and authors this week. The governments were keen to ensure an unbiased interpretation and presentation of the findings of the climate scientists, as well as those stemming from the assessment of experiences of disaster risk management at local, national and global levels, and of the opportunities to manage future climate extremes and reduce vulnerability.

Your reaction to the report's findings reflects badly on you and calls into question the sincerity of your previous enthusiastic defence of the IPCC.
Will better reporting of the science by the IPCC change anyone's opinion on climate change? Probably very few people.  But it may have allowed the IPCC to take an important step in the direction of renewed credibility.