Greenland's massive ice sheet could begin to melt this century and may disappear completely within the next thousand years if global warming continues at its present rate.

...the global surface temperature increased 0.6° Celsius (1.8° Fahrenheit) in the last century. Oceans have become warmer, too, expanding while storing heat. This has caused sea levels to rise 4 to 8 inches (10 to 20 centimeters) in the last hundred years.