Arctic Ocean Ice Extent
January 06, 2003
The above is a composite Radarsat image of the Arctic Ocean area, taken on August 21, 2000. Using advanced radar that sees through all weather conditions, scientists at NASA's Jet Propulsion Laboratory have mapped the Arctic Ocean in unprecedented manner allowing researchers to determine how the Earth's recent warming may be changing the sea ice cover. Sea ice in the polar regions may be a barometer of global climate change.
According to recent NASA studies, the perennial sea ice in the Arctic is melting at about 9% per decade, faster than previously thought. If these melting rates continue for a few more decades, the perennial sea ice could completely disappear entirely within this century. It was also found that temperatures in the Arctic are increasing at the rate of 1.2 degrees Celsius (2.2 Fahrenheit) per decade. The rate of ice decline is expected to accelerate due to positive feedback systems between the ice, oceans and atmosphere. In fact, observations have shown that this past year's perennial ice cover is the least extensive observed during the satellite era. Comparing the differences between Arctic sea ice data from 1979 to 1989 and data from 1990 to 2000, the most melting occurred in the western Arctic Ocean - Beaufort and Chukchi Seas. It should be noted, however, that perennial sea ice actually advanced in a few areas east of Greenland.