One of the common themes of the creation wars and the climate war is the attempt by the anti-science side of each debate (ie, creationists and AGW deniers) to make their position appear more reasonable than it is by arguing that it is accepted by a large number of scientists. Thus we have lists of scientists who do not accept evolution such as that compiled by the Discovery Institute, and equivalent lists of scientists who do not accept Anthropogenic Global Warming such as the OISM petition from the forces of anti-science.
To counter this spurious argument, defenders of science have emphasized how small a proportion of scientists accept these pseudo-scientific positions. The NCSE does this with some humour, through their Project Steve. Defenders of the theory of AGW are a bit more dour, and have produced a series of surveys and other studies showing that rejection of AGW is confined to about 3% of climate scientists.
The curious thing is that these studies are rejected in turn by AGW deniers as an appeal to authority, ie, and invalid argument. Their intention is nothing of the sort. Rather, they are a rebuttal of the spurious appeal to authority represented by such phenomenon as the OISM petition. Ignoring that important subtlety, however, the fact remains that an appeal to relevant authority is in fact a valid way of justifying beliefs. I recently explained why in some detail in a comment at Skeptical Science, which is reproduced with minor editing below the fold.