The Current Shift

The newest shift is the fastest. Since 1979, the tropical belt has been creeping outward by roughly half a degree of latitude per decade, nudging dry, desert-like conditions toward lands that used to be temperate. Gardeners can already feel it: the plant hardiness zones they rely on have crept steadily northward across the United States.

Living things are trying to follow their climate uphill and poleward. But forests move at the pace of seeds and saplings — far slower than the zones themselves are sliding. Animals can sprint ahead, yet they still depend on the plants, soils, and food webs left behind. The danger isn't the warming alone; it's that the speed outruns nature's ability to keep up.