There's a discussion going on at Aardvarchaeology and Respectful Insolence about skepticism and scientific consensus. Should skeptics always side with the scientific consensus? Martin and Orac agree that we should, provided that there is a sufficiently unambiguous consensus. I agree, though I would add the further qualification that this rule does not always apply to experts in their own fields. Perhaps a better qualification (as one commenter suggested) is that the scientific consensus is only the default position of skeptics.
Why would we think this? Isn't it characteristically anti-skeptical to unquestioningly accept authority, scientific or otherwise?
Let's first look at which sorts of people are "skeptical" of the scientific consensus. There's Global Warming deniers, Intelligent Design proponents, racists, parapsychology proponents, alternative medicine proponents, the antivaccinationists, and relativity deniers. Orac also offers an example from social science: Holocaust denial. If you deny accepted science, you're in the company of the biggest opponents of skepticism. On the other hand, we might also include major scientific revolutionaries like Einstein, Galileo, and Darwin. However, in all these cases, the revolutionaries were all experts in their fields, they started from the default position that the consensus is correct, and the scientific consensus soon came to agree with them.
Relying on scientific authority is not the same as the fallacy of "argument from authority". The reason that argument from authority is fallacious is because an argument is an argument regardless of who says it. It doesn't matter if the person who makes the argument is an average Joe, a scientific expert, or the president--our acceptance or rejection of the argument ought to rest on the argument's merits, not the person's authority. However, scientific authority is different, because whenever scientists agree on a claim or argument, there is always some evidence backing them up, even if the general public cannot see it or understand it. Scientific authority comes from the fact that scientists have a much better grasp of the entire field of evidence then the public could ever hope to attain.
So what is a science layman to do? Should they accept the scientific consensus, or should they avoid taking any position (leaving that up to the scientists)? I think that some people like to avoid taking any position because there is a fear of being wrong. But I would argue that it is equally wrong to take the neutral position if one of the sides is the clear winner. For example, I know very little about Global Warming aside from a lecture about Milankovitch cycles and a lecture about carbon dioxide sources and sinks. I would be wise to avoid debating the topic, but wouldn't it be wrong to avoid voting with Global Warming in mind? Just because I don't understand it does not make it less supported by evidence, or less important.
One last thing worth noting is that this doesn't mean we shouldn't question science. Questioning is often a good way to learn.