Drought-hit regions bleeding those for whom a rural life has become untenable. Coastlines diminishing year on year. Wildfires and hurricanes leaving widening swaths of destruction. The culprit, most of us accept, is climate change, but not enough of us are confronting one of its biggest, and most present, consequences: a total reshaping of the earth’s human geography. As Gaia Vince points out early in Nomad Century, global migration has doubled in the past decade, on track to see literal billions displaced in the coming decades. What exactly is happening, Vince asks? And how will this new great migration reshape us all?