Death at UAH

As I was about to write up the latest smoggy stuff, I thought I’d better check out Eli in case he had written it up first. And lo, I thought, Condolences referred to the death of Christy’s scientific reputation. But no, it is about real death. So I need to press on.

[[John Christy]] has been a bit of a skeptic for ages. Quite where he gets it from is unclear – perhaps because he and Spencer did the first version of the [[satellite temperature record]] and, well, they got it wrong. In that it showed cooling, and so they became the poster boys for the real septics like Singer and Michaels and Inhofe. Perhaps some of that seeped in. But it turned out that a longer record showed a different answer, and that their version needed a pile of corrections, and when you do all that it shows warming. In the course of this long slow unravelling they got a fair amount of justified stick; and perhaps that pushed him towards the Dark Side.

But he was still a reputable scientist, somewhat in the mould of Lindzen though less eminent. Whilst clearly on the skeptical side he retained his k. The wiki page can’t really work out what to say about his views, which is correct, as it is hard to wade through the morass of conflicting stuff, and ends up with While he supports the AGU declaration and is convinced that human activities are one cause of the global warming that has been measured, Christy is “still a strong critic of scientists who make catastrophic predictions of huge increases in global temperatures and tremendous rises in sea levels.”

However, he got sucked in the the septic tide and published some stuff with Douglass in IJC in 2007 that was fundamentally flawed (Santer’s letter explains the details). The septics puffed it up; but it all fell apart a year later when Santer et al. ripped it to shreds, but of course there was a year of PR down the drain by then. Now Christy, I think, is not very strong on stats, and may well not have realised the error at the time of publication (though he should have known, because it had already been rejected from another journal for the same error). And a combination of pride, and of refusing to be corrected by the “other side”, and perhaps pressure from his co-authors, meant he never admitted to the error. Nor, as Santer points, did he ever attempt to defend it – defend in a proper scientific sense that is, not just in the sense of saying “we were right”. Instead he has a rather nasty piece which entirely evades the scientific issues (I don’t think their appendix A cuts it). They seem to complain that they never had a chance to respond to Santer’s paper which is odd – they had, and still have, every chance to write a proper response. Just like Santer et al. did. Instead, they chose to evade and whinge.

As Santer said, the paper that ended in IJC was intended for GRL. GRL is a far higher status journal, and has better quality reviewers, including Santer, and these reviews had already spotted the error. IJC is quite a lowly journal, and an odd choice for Americans, and looks like it was deliberately chosen as a journal of last resort for a dodgy paper. Christy relies rather heavily on selective quotes from leaked emails to make his case that the world is against him; it would be rather interesting were he to release the review comments on his paper.

[Update: Santer’s appendix A is here. Thanks Eli -W]