This one is for my son, Ian. Years ago before the Internet, when social media was dial-up and I had an account on the Whole Earth ‘Lectronic Link, I read a post speculating about a new theory, that ocean warming could cause a state change in the oceanic currents that keep Europe warmer than other places with similar latitudes (for example, northern Canada). Not a gradual temperature shift, but more like flipping a switch.  If such a thing happened, the average temperature in Europe would quickly plummet, making traditional agriculture as it’s currently practiced in traditional locations difficult or impossible.  This in turn would significantly affect Europe’s ability to feed itself.

The theory has become well-accepted. This week I read that the consensus is now that there’s a 50% chance that the state change will happen this century, and a substantial chance that it happens by 2050.