That 13 million includes a heck of a lot of non-climate scientists. This is fascinating, considering that up until now it's been a given for pro-AGW activists that skeptical non-climate scientists are to be completely ignored on the subject, no matter how brilliant they are in their own field.

In fact, the Petition Project has been criticized precisely because not every last person who signed it is officially a "climate scientist." The qualifications of the signers are discussed here.

Of course, with the usual liberal inconsistency, if the person is pro-AGW, this rule does not apply. For example, Rajendra Pachauri, chair of the IPCC, is an industrial engineer and romance novelist.

It's kind of a moot point, since the whole thing is blowing up in the U.N.'s face.