GMU law prof Todd Zywicki has a thoughtful post on climate change policy on the Volokh Conspiracy. An excerpt:

the real question to ask here is whether on net, the costs of doing something about global climate change outweigh the benefits of doing it. This is the same question we ask (or should ask) about every other intervention into nature--should we kill the parasites in water so that we can drink it, should we drain a mosquito-infested swamp to eliminate the risk of malaria, should we provide a vaccine to kill naturally-occurring smallpox. To imply that if the science shows we are changing the climate we must do something about it is as wrongheaded as it would be to say that if we are not contributing to global warming we should not do anything about it.