It's not an exaggeration to say that "virtually none of the climate-change deniers have a clue about the underlying science". I mean, next time you have a conversation with one, ask them to discuss, in broad terms, the Earth's heat budget. Ask them to describe the roles played by CO2 and H20, and to explain how they're different. In my experience, mostly people are just spewing bullshit that they've heard. They're driven by ideology and religion, not data and sound models.