The risks of unchecked global warming are now widely acknowledged: a rise in sea levels threatening the existence of some low-lying coastal communities; pressure on freshwater resources, making food production more difficult in some countries and possibly becoming a source of societal conflict; changing weather patterns providing favorable conditions for the spread of malaria. To make matters worse, the effects will be felt most in those parts of the world which are home to the poorest people who are least able to protect themselves and who bear the least responsibility for the build-up of greenhouse gases (GHGs). Concern has been great, but humanity has so far done very little that will actually prevent these outcomes. Carbon emissions have kept increasing, despite repeated promises of cuts.

As I wrote in The Skeptical Environmentalist (Lomborg 2001), man-made global warming exists. There is still meaningful and important work going on looking at the range of outcomes that we should expect but it is vital to emphasize the consensus on the most important scientific questions. We have long moved on from any mainstream disagreements about the science of climate change. The crucial, relevant conversation of today is about what to do about climate change – the economics of our response.

Finding a better response to global warming has become all the more important as the current political approach – seen at summits in Rio de Janeiro, Kyoto, and Copenhagen, has seemingly run aground.