It’s getting hot out there. Every one of the past 14 months has broken the global temperature record. Ice cover in the Arctic sea just hit a new low, at 525,000 square miles less than normal. And apparently we’re not doing much to stop it: according to Professor Kevin Anderson, one of Britain’s leading climate scientists, we’ve already blown our chances of keeping global warming below the “safe” threshold of 1.5 degrees.
If we want to stay below the upper ceiling of 2 degrees, though, we still have a shot. But it’s going to take a monumental effort. Anderson and his colleagues estimate that in order to keep within this threshold, we need to start reducing emissions by a sobering 8%–10% per year, from now until we reach “net zero” in 2050. If that doesn’t sound difficult enough, here’s the clincher: efficiency improvements and clean energy technologies will only win us reductions of about 4% per year at most.
How to make up the difference is one of the biggest questions of the 21st century.