August 10, 2009

Arctic Ice Melting Quickly

Scientists continue to keep a close eye on the Arctic Ocean, which has given up tens of thousands of square miles of ice this summer.

Eddie Gruben, a local observer in far northwest Canada, told the Associated Press he has watched the summer ice retreat for years. By this weekend the ice edge lay 80 miles at sea.

"Forty years ago, it was 40 miles (64 kilometers) out," added Gruben, 89.

According to researchers, the global average temperature rose 1 degree Fahrenheit over the past century, but the Arctic temperature has risen twice as much.

In July, the temperatures rose to almost 86 degrees Fahrenheit in the settlement of Inuvialuit.

"The water was really warm," Gruben told the Associated Press. "The kids were swimming in the ocean."

According to the U.S. National Snow and Ice Data Center, the polar ice cap has shrunk an average of 41,000 miles per day in July, equivalent to one Indiana daily.

The ice is melting at a rate similar to that of July 2007, the year when ice cap melting hit a record low.

According to the center's Walt Meier, the acceleration of ice loss has slowed making a record-breaking minimum "less likely but still possible."

Researchers say the makeup of the frozen polar sea has also changed over the last few years from a thick multiyear ice to a thin ice that comes and goes.

The last few years have "signaled a fundamental change in the character of the ice and the Arctic climate," Meier told the AP.

Since 2007, the channels of the Northwest Passage, the east-west water route through Canada's Arctic islands, have seen patches of thick ice drift into and block narrow passageways.

"We need some warm temperatures with easterly or southeasterly winds to break up and move this ice to the north," said Mark Schrader, skipper of the sailboat "Ocean Watch."

Schrader and his vessel are on a 25,000 mile foundation-financed mission to circumnavigate the Americas and study climate change's impact on the continents.

In September, observation satellites will tell scientists whether the polar cap has diminished to the smallest size on record.
In the fall, the sun will fall below the horizon and leave the sea in a polar darkness where it will freeze again.  The sea ice will form as a weaker, thinner ice, however.

Last March, scientists announced that climate change was happening faster than expected, pointing to the dwindling polar ice cap as an example.

The U.S. National Oceanic and Atmospheric Administration believes Arctic summers could be nearly ice-free within 30 years.


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