HOW THE CONSENSUS IS CONTRIVED AND SUSTAINED
Paul Biggs <p.m.biggs@bham.ac.uk>
From the blog of climate modeller James Annan - an example of how 'consensus' is contrived and sustained:
Another week, another rejection (without review) from Nature. This was an attempted comment on Hegerl et al <HYPERLINK "http://julesandjames.blogspot.com/2006/04/hegerl-et-al-on-climate-sensitivity.html"http://julesandjames.blogspot.com/2006/04/hegerl-et-al-on-climate-sensitivity.html> , which can be found here <HYPERLINK "http://www.ne.jp/asahi/julesandjames/home/comment_on_hegerl.pdf"http://www.ne.jp/asahi/julesandjames/home/comment_on_hegerl.pdf> . The points we were trying to make will not come as a surprise to anyone who has read my previous comments such as the comment on Frame et al <HYPERLINK "http://julesandjames.blogspot.com/2006/03/comment-on-frame-et-al.html"http://julesandjames.blogspot.com/2006/03/comment-on-frame-et-al.html> which we are still waiting to hear anything about, after a full 2 months at GRL. Basically, there are two main reasons why Hegerl et al's "pdf" is not actually a valid probabilistic estimate of climate sensitivity at all. Firstly, they ignore much of the data that bears on the matter (and which indicates a highest likelihood of a value of about 3C), and secondly by starting off with a prior that assigns very high probability to high sensitivity and ignoring most of the evidence to the contrary, they ensure that the result also has a high probability of high sensitivity - albeit far lower than their prior did. Of course these...limitations...are prevalent in much of the literature.
Nature's excuse this time? Editor Nicki Stevens wrote:
we have regretfully decided that publication of this comment as a Brief
Communication Arising is not justified, as the concerns you have raised
apply more generally to a widespread methodological approach, and not solely to the Hegerl et al. paper
Yes, you read that right. Because everyone else has been doing much the same thing, they aren't interested in ensuring that the stuff they publish is valid. Really, there seems little answer to this beyond picking our jaws off the floor and keeping it in mind when we read future Nature papers. (FWIW, it was also Nicki Stevens who told us that our GRL manuscript didn't provide enough of an "advance in significantly constraining climate sensitivity relative to prior estimates".)
Meanwhile, we have people like Gavin Schmidt quite prepared to openly dismiss the bulk of peer-reviewed literature in this area with such comments as "Basically no one really believes that those really high sensitivities are possible," <HYPERLINK "http://news.nationalgeographic.com/news/2006/04/0419_060419_global_warming_2.html"http://news.nationalgeographic.com/news/2006/04/0419_060419_global_warming_2.html> and "even Hegerl's top limit is too high" <HYPERLINK "http://www.realclimate.org/index.php/archives/2006/04/how-not-to-write-a-press-release/#comment-12079"http://www.realclimate.org/index.php/archives/2006/04/how-not-to-write-a-press-release/#comment-12079> . Not that I'm criticising him for that - quite the reverse, but the fact that there is such a credibility gap between what has appeared in the literature, and what at least some responsible and reputable scientists think, should surely be seen as rather worrying by all who are interested in ensuring that the scientific process works as intended. It is quite clear that (unless our arguments are wholly invalid, and so far no-one has suggested why they should be) none of the published "pdfs" actually provide any credible support for the belief that S is greater than 6C even at as little as the 5% level (for example), but according to Nature, as long as everyone keeps on getting this wrong together, they aren't interested in correcting the mistaken (and alarmist) impression that they have helped to foster. We feel like the boy who tells the emperor that he has no clothes, except that we are not even being allowed to say it, at least not anywhere that it will be seen.
HYPERLINK http://julesandjames.blogspot.com/ http://julesandjames.blogspot.com/
Regards,
Paul Biggs