As glaciers melt amid the heat of a warming planet, scientists predict that coastal communities in the United States could eventually experience flooding from higher tides. Conservative estimates range from an increase of about one to four feet in sea-level rise by the end of the century. Experts also warn that people should be prepared for unlikely but extreme scenarios of up to eight feet in sea-level rise, which would cause severe and chronic flooding in hundreds of coastal cities. Grappling with this problem would be expensive for local governments.