There is another post over at Watts Up With That (WUWT) claiming that John Cook’s consensus paper is falling apart. They seem rather fixated by this paper, which is interesting in itself. Anyway, it’s based on a post on Bishop Hill called landmark consensus study is incomplete.
The Bishop Hill post, by Shub Niggurath, says
A Web of Science search performed following the authors’ description to the letter actually returns 30,940 entries, not 12,464. Excluding the ‘Arts and Humanities Citation Index’ (A&HCI), this becomes 30,876. This is when search phrases are not enclosed in double-quotes (i.e., ‘global warming’ instead of “global warming”).
Well, if you do use double-quotes instead of single-quotes and restrict the search to articles only, you find 12,574 articles – essentially the same as Cook et al. Well, that explains why they got a different result to Cook et al., and rather disproves Shub Niggurath’s claim that he followed the authors’ description to the letter.
However, have they found that Cook et al. missed a lot of relevant papers. I don’t think so. If I do a search using single-quotes it returns results for ‘climate change’ and ‘global’, whereas using double-quotes restricts it to results for “global warming” and “global climate change”. So, basically the author of the Bishop Hill post has shown that if you do a topic search different to that of Cook et al., you get a different number of articles. They haven’t really shown that Cook et al. missed a lot of relevant papers. However, even if they have, it doesn’t really matter. Even if there are 30000 relevant articles, rather than 12474, it doesn’t invalidate the study. What they used was a large fraction of the relevant articles and hence would, typically, be regarded as a representative sample. The uncertainty in the result might increase slightly, but not enough to make the consensus particularly uncertain.