I recently stumbled across this very interesting YouTube post entitled "How It All Ends." Aside from the neato tricks and odd costume, the author, Greg Craven, makes a pretty strong argument. He presents the issue of climate change as a risk management issue rather than focusing on the scientific evidence supporting or refuting climate change. I think that makes his presentation difficult to argue against and more widely understood by an audience of varying technical backgrounds. It also takes the political component out of the equation, and boils this debate down to the real issue.
If it's true, we're all in trouble without action. If it's not, then the only costs would be economic, and they pale in comparison to the former outcome. We should approach climate change the same way we do with illnesses. When you get really sick, you go to the doctor to get pills (which usually have an economic cost) to reverse chemical processes that are deteriorating the systems within your body. You don't sit at home and wait to see if the illness will be fatal before you seek treatment. Personal health isn't a political issue, and neither should be environmental health.