Science reporter, BBC News, San Francisco
Their latest modelling studies indicate northern polar waters could be ice-free in summers within just 5-6 years.
Professor Wieslaw Maslowski told an American Geophysical Union meeting that previous projections had underestimated the processes now driving ice loss.
Summer melting this year reduced the ice cover to 4.13 million sq km, the smallest ever extent in modern times.
Remarkably, this stunning low point was not even incorporated into the model runs of Professor Maslowski and his team, which used data sets from 1979 to 2004 to constrain their future projections.
"In the end, it will just melt away quite suddenly"
Taken on Aug. 29, 2007, this image below shows the opening of the Northwest Passage (red line), which was the most navigable that people have seen since monitoring began. Credit: National Snow and Ice Data Center
SAN FRANCISCO—Clouds were likely a culprit in this summer’s record Arctic meltdown which temporarily opened up the fabled Northwest Passage, scientists announced today.
While Earth’s rising temperatures fueled by global warming are certainly a factor in the Arctic melt, unusual weather patterns this summer also influenced how much of the sea ice melted.
One result of these patterns was a decrease in cloud cover, scientists said today at a meeting of the American Geophysical Union, which would have allowed more sunlight to penetrate Earth’s atmosphere and warm the Arctic ocean waters.
New data from NASA satellites observing the western Arctic, where most of the ice loss occurred, showed a 16 percent decrease in cloud coverage this summer compared to 2006.
"There’s been quite dramatic reductions of cloudiness this summer," said study member Graeme Stephens of Colorado State University.