But below the surface, the ice sheet is in constant motion, as ice built up in the interior pushes toward the coast in the form of massive glaciers. During warmer months, ice from these glaciers melts into the ocean.
It's an age-old process that scientists say has sped up in recent decades because of global warming.
The fear is that melting ice from Greenland and other Arctic areas could cause sea levels to rise enough to flood low-lying cities, such as Shanghai, China, and New York City, displacing millions of people in the process.
A recent report from the U.N.'s Intergovernmental Panel on Climate Change, made up of scientists from around the world, estimates the sea level rise by 2100 could be as much as 1½ feet. Source: www.cnn.com
This would be very scary if it really flooded the cities mentioned in the article. Global Warming.