April 06, 2009, 8:26 PM — Arctic sea ice, which acts as the world's air conditioner, continued to shrink this winter as the ice cap grew thinner, according to NASA researchers.
This winter had the fifth lowest total area of the arctic covered by ice since scientists began tracking it 30 years ago. NASA's Jet Propulsion Laboratory also reported today that according to satellite observations the six thinnest polar ice covers have come in the past six years.
"Ice extent is an important measure of the health of the Arctic, but it only gives us a two-dimensional view of the ice cover," said Walter Meier, research scientist at the National Snow and Ice Data Center and the University of Colorado in Boulder, in a statement. "Thickness is important, especially in the winter, because it is the best overall indicator of the health of the ice cover. As the ice cover in the Arctic grows thinner, it grows more vulnerable to melting in the summer."
Last year, a team of researchers led by scientists at the Jet Propulsion Laboratory in Pasadena, Calif., created the first map of sea ice thickness for the entire Arctic basin, according to NASA. The scientists used two years of data compiled from NASA's Ice, Cloud, and Land Elevation Satellite (ICESat).
The Jet Propulsion Laboratory noted that Arctic sea ice acts as an air conditioner for the climate system not just in the north but around the world. Ice cools air and water, is a critical factor in ocean circulation, and reflects solar radiation back into space.
The problem is that in recent years, the ice in the Arctic sea has been declining at what scientists call a surprising rate.
Historically, Arctic sea ice lasted not only over one summer but often over several years. Charles Fowler, head of a team of scientists from the University of Colorado at Boulder, reported that thicker ice that is able to last for two or more years now only makes up 10% of the ice cover. That's down from 30% to 40% in the 1980s and 1990s.
A little more than a year ago, the Discovery Channel launched a new 3-D application called Earth Live that enables users to interact with scientific data and visualize events like climate change and polar melting in real time.
Using data collected from NASA and the National Oceanic and Atmospheric Administration, people, for instance, can track storms in real time or track how increasing temperatures at the polar ice caps threaten to raise sea levels.