And today, more than

No one can say exactly how hot the world can get before out-and-out disaster—the inundation of a populous country like Bangladesh, say, or the collapse of crucial ecosystems like coral reefs—becomes inevitable. Officially, the threshold of catastrophe is an average global temperature rise of 2°C (3.6°F). Virtually every nation signed on to this fig

The facts are brutal. To stay under 1.5°C, the global economy can burn only a fixed amount more carbon, which at time of publication, the Mercator Research Institute on Global Commons and Climate Change estimated at approximately 275 gigatons and