The Evangelical Ecologist has an excellent post on the value of skepticism in the appropriate place, and also touches on where it is appropriate.
He says:
There is an important distinction, then, between aggressively promoting environmental stewardship as a God-ordained moral ethic (which it is), and aggressively promoting a particular area of human-derived environmental science as a moral ethic (which it is not).
I think he makes a couple of excellent points in this post. I’ve been trying to find time to link to some of his stuff since I first found the site a few weeks ago, but I haven’t had the time. Go over and check it out.