First things first: MERRY CHRISTMAS! And if you don't celebrate it, happy Thursday!
Second things first: What are you doing reading blogs today? :p
Okay. So, I think the evidence for Global Warming is pretty strong. I know just enough chemistry to be dangerous when I read over the papers on the subject, and enough about modelling to know that what climate modellers are doing is by and large legit. Partially, I trust the peer-review process, where scientists love to prove eachother wrong, and partially, I trust expertise - arguing about climatic science is like arguing about how things work inside a nuclear reactor, in that I'm ignoring the hell out of the person who isn't a nuclear chemist/physicist when they go on about the subject.
I don't need to place much faith in them, though, because there's many strong lines of biological evidence, not the least of which is the shifting of plant communities. And as Filmore's Bathtub - a blog from Utah - writes, even a lay person can see what's going on. This guy used to be a staffer for Sen. Hatch (R-UT), once upon a time, and is now an educator. He runs a neat blog, though one that's become increasingly left - it seems he's one of the many that the last 8 years of Bush have alienated from their party.
Here's the money shot:
Plants don't have a political agenda. They do, however, know when its getting warmer.