Have you heard the latest joke about emissions trading? There was this factory in China that produced so much carbon dioxide from coal they had to get rid of it somehow. So they sold it to Coca-Cola. We shall burp away in the cause of carbon sequestration, imaginatively interpreted. Somewhere in the joke is a kernel of truth. If there’s a buck to be made from climate change, there’ll be someone, somewhere, who’ll be making it, and we’re right to be suspicious.

Climate change and why we disagree about it are two major issues of our times. Mike Hulme, professor of climate change at the University of East Anglia, finds that such talk is universal, in science, the arts, law, business and government. He takes climate change to mean a past, present or future change in climate, some of which may be caused by humans. Climate change is both a physical and a social reality. What also matters is the meaning of climate change, and what happens to this idea as it enters the social repertoire of our quarrelsome species. Why can’t we begin to agree about such a serious issue and thus do something about it? Why can’t we all play nicely together?