sea level rise

From the water's edge in Norfolk, Va., the U.S. naval base spans the whole horizon. Aircraft carriers, supply centers, barracks and admirals' homes fill a vast expanse.

But Ray Toll, a retired naval oceanographer, says the "majority of [the naval base], if not all of it" is at risk of flooding "because it's so low and it's flat."

Skip Stiles stands on the edge of a small inlet known as the Hague, near downtown Norfolk, Va. The Chrysler Museum of Art is nearby, as are dozens of stately homes, all threatened by the water.