By Erin Wayman
The threat of rising seas is not new. Since the last Ice Age began windingdown 15,000 years ago, the ocean has ascended 120 meters in a series of pulses. But when the world was thinly populated, small bands of hunter-gatherers could pick up and go when the sea surged. Now that hundreds of millions of people are settled in crowded coastal cities, the rising seas predicted for a warming world are more dangerous than ever, argues Fagan, an archaeologist.