It is, I promise, worse than you think. If your anxiety about global warming is dominated by fears of sea-level rise, you are barely scratching the surface of what terrors are possible, even within the lifetime of a teenager today; the young people that are our own children and grandchildren. And yet the swelling seas — and the cities they will drown — have so dominated the picture of global warming, and so overwhelmed our capacity for climate panic, that they have occluded our perception of other threats, many much closer at hand. Rising oceans are bad, in fact very bad; but fleeing the coastline will not be enough.

Absent a significant adjustment to how billions of humans conduct their lives, parts of the Earth will likely become close to uninhabitable, and other parts horrifically inhospitable, sooner than the end of this century. Some say we are already past the point of no return. Some deny the problem even exists, because such an idea is contrary to amassing even more wealth than they have today. But what good will wealth be when there are no longer farms to grow food, no fish in the ocean, no places to live without drowning or baking.