EFFECTS OF GLOBAL WARMING
Scientists expect global warming to affect Earth in many ways. Melting of glaciers and the polar ice caps could cause sea levels to rise. In the 20th century, sea levels rose 0.1 m to 0.2 m. By 2100, scientists estimate it will rise 0.5 m more, flooding many coastal areas.

Some predict that by 2080, floods will threaten New York City's rail subway and road tunnels.

Rainfall patterns may change, causing more frequent droughts in continental interiors. More snowfall, rainstorms, and hurricanes in other areas could cause flooding. Scientists predict water shortages in arid areas in the American West.