Humans live where there’s water. Commerce, shipping, and fishing provide extra incentives to live along coasts. Coastal populations continue to grow, even as sea level rise threatens housing. If we were truly responding to climate change, new growth would be happening inland rather than along the shore. Instead, almost a billion people are living in areas affected by sea level rise, and the number exposed to flooding is rising from 189,000,000 in 2000 to 411,000,000 by 2060. Humans learn, but it take a while before many leave and turn the tide.