Benny Peiser highlighted an analysis of the IPCC peer review process, by climate data analyst John McLean:
In "Peer Review? What Peer Review?" McLean writes, "The IPCC would have us believe that its reports are diligently reviewed by many hundreds of scientists and that these reviewers endorse the contents of the report. Analyses of reviewer comments show a very different and disturbing story."McLean has followed up with an email:
In Chapter 9, the key science chapter, the IPCC concludes that "it is very highly likely that greenhouse gas forcing has been the dominant cause of the observed global warming over the last 50 years". The IPCC leads us to believe that this statement is very much supported by the majority of reviewers. The reality is that there is surprisingly little explicit support for this key notion. Among the 23 independent reviewers just 4 explicitly endorsed the chapter with its hypothesis, and one other endorsed only a specific section.
Moreover, only 62 of the IPCC's 308 reviewers commented on this chapter at all. As with other chapters, simple corrections, requests for clarifications or refinements to the text which did not challenge the IPCC's conclusions are generally treated favourably, but comments which dispute the IPCC's claims or their certainty are treated with far less indulgence.
As the author of the article in question I'd like to point out that
subsequent to the writing of that paper I have found that 2 more
reviewers of the pivotal 9th chapter had a vested interest in the
One of was from an IPCC technical support group and the other was
responsible for the "Frequently Asked Questions" in the
report. (Yes, we can puzzle over who might have been frequently
asking those questions!)
That brings the numbers to 62 reviewers in total for chapter 9, 8 of
whom of were government representatives, 23 with a vested interest
and just 21 who appear to be impartial. The total explicit support
for the IPCC's claim came from just 4 reviewers, one incidentally
being a government representative.
Overwhelming endorsement? Not exactly...