More stuff I wrote elsewhere:

Houck's disquisition does beg an important question, which is what policymakers should do in the face of genuine uncertainty. Greenhouse-induced climate change is a case in point. While there seems little scientific doubt that we're changing our climate, the details of how that climate change will play out are hugely uncertain, as are the effects on the climate system of various greenhouse-gas mitigation strategies.

So what's a policymaker to do? It's a legitimately hard problem.