Suggested reading:

"On Experts and Global Warming" by Gary Gutting, a professor of philosophy at the University of Notre Dame. Gutting's article was posted yesterday (July 12) on the Opinionator blog of the NY Times.

The takeway paragraph from this excellent blog:

The essential point, however, is that once we have accepted the authority of a particular scientific discipline, we cannot consistently reject its conclusions. To adapt Schopenhauer’s famous remark about causality, science is not a taxi-cab that we can get in and out of whenever we like. Once we board the train of climate science, there is no alternative to taking it wherever it may go.

http://www.skepticalscience.com/thread.php?t=2238&r=5