"Let's be realistic." That's the advice coming from a growing number of voices in climate circles in the United States. In October, billionaire Bill Gates argued that a global temperature rise of 2 degrees Celsius is unavoidable and not a " super bad outcome"-a view unlikely to be shared by the millions of people whose homes would be destroyed by the resulting killer storms and rising seas.
All is not lost, Simon Stiell, the UN's climate chief, told the Guardian last week. But the latest planetary health check from the Potsdam Institute for Climate Impact Research is a brutal reminder of how close the Earth is being pushed beyond repair. Seven of the nine planetary boundaries are now breached, with ocean acidification added to the danger list. Yet the world has proved that cooperation works: the ozone layer is healing, air pollution controls are working.
