The scientific message about human-induced climate change is both unequivocal and urgent. Following last year’s reports by the Intergovernmental Panel on Climate Change, further studies have been published that show beyond all reasonable doubt that humans have already caused significant changes to the climate. Science also tells us that we have very little time left to put on the brakes before the risks become catastrophic.

Already, through deforestation and our use of fossil fuels, we have reached levels of carbon dioxide that the earth has not experienced since the cycle of the ice ages began some 3m years ago. The good news is that we seem to have cancelled the next ice age. The bad news is that we are heading for an earth that is hotter, with sea levels higher than humans have experienced.