National Center for Atmospheric Research (NCAR)

April 21, 2008

Arctic Ice More Vulnerable to Sunny Weather, New Study Shows

http://www.ucar.edu/news/releases/2008/arcticice.jsp

BOULDER-The shrinking expanse of Arctic sea ice is increasingly vulnerable to summer sunshine, new research concludes. The study, by scientists at the National Center for Atmospheric Research (NCAR) and Colorado State University (CSU), finds that unusually sunny weather contributed to last summer's record loss of Arctic ice, while similar weather conditions in past summers do not appear to have had comparable impacts.

The study, which draws on observations from instruments on a new group of NASA satellites known as the "A-Train," will be published tomorrow in Geophysical Research Letters. It was funded by NASA and the National Science Foundation, which is NCAR's principal sponsor.

"In a warmer world, the thinner sea ice is becoming increasingly sensitive to year-to-year variations in weather and cloud patterns," says NCAR's Jennifer Kay, the lead author. "A single unusually clear summer can now have a dramatic impact."

The findings indicate that summer sunshine in the Arctic produces more pronounced melting than in the past, largely because there is now less ice to reflect solar radiation back into space. As a result, the presence or absence of clouds now has greater implications for sea ice loss.

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The above paragraphs are excerpts. For the complete press release, go to:

http://www.ucar.edu/news/releases/2008/arcticice.jsp

posted to ClimateConcern

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