t 50 to 100 years. Just a 1 foot rise
             in sea level can cause shorelines to recede a hundred feet, and in flat terrain, a
             thousand feet. If ocean waters rise several feet, whole beaches could wash
             away. Many homes, hotels, other buildings, and entire cities will be
             threatened. Salt water will pollute freshwater wells that millions of people use
             for drinking water. Coastal marshes, which are vital nurseries for fish and
             other ocean life will be endangered. Along undeveloped coast, marshes may
             survive because they can move inland with the rising waters. In many places
             seawalls and other human structures will prevent this process and the marshes
             will be destroyed. In the United States ocean water may cover the Florida
             Keys and large parts of southern Florida and Louisiana. Two kinds of action
             are called for. One is to take steps to prepare for the the effects of warming
             that already have begun. Agricultural scientist
             ...