Feature Earth

Climate’s Long-Lost Twin

A warm spell in the distant past holds soggy clues to the future

By Richard Monastersky

- More than 2 years ago

Clinging to a cliff in the Bahamas, high above the pounding surf, geologist Paul J. Hearty takes care to avoid any missteps as he surveys the craggy rock.

Along the coast of Chile, this raised terrace was a beach 400,000 years ago.

Head for the hills: A 10-meter rise in sea level (red) would flood 63 million people along the East and Gulf Coasts of the United States.