We Made This Heat, Now We Cool It

Just how hot can the Earth get before our ongoing mass-extinction event hammers humans in unbearable ways? An initial estimate scientists made in the mid-1990s called for keeping the rise in global average temperature below 2C. This summer finds us approximately halfway there, and even closer to a revised safety threshold of 1.5C.

There’s another way to think about this, an angle that tends to attract experts in economics and other social sciences: Since apparently we are going to heat the world well beyond the level scientists advise, perhaps even as far as 3C, humans will simply adapt as we always have. What must be done can be done.