April 27, 2015
No one knows, exactly. Think of 2°C like a sort of speed limit — or a zone of increased risk. Katharine Hayhoe, a climate scientist at Texas Tech, told me that burning fossil fuels is like smoking. How many cigarettes give you cancer? No one knows, exactly. But the more you smoke, the more you up your risk. And 2°C, policy experts agree, is certainly risky territory.
Plus, everyone hates a fraction.