Paul Krugman: Loading the Climate Dice

A couple of weeks ago the Northeast was in the grip of a severe heat wave. As I write this, however, it’s a fairly cool day in New Jersey, considering that it’s late July. Weather is like that; it fluctuates.

And this banal observation may be what dooms us to climate catastrophe, in two ways. On one side, the variability of temperatures from day to day and year to year makes it easy to miss, ignore or obscure the longer-term upward trend. On the other, even a fairly modest rise in average temperatures translates into a much higher frequency of extreme events — like the devastating drought now gripping America’s heartland — that do vast damage.