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Posts Tagged ‘Arctic sea’

Melting Arctic Ice Marks Possible Sea Change in Marine Ecosystems

June 27, 2011 Comments off

livescience

Arctic Sea Ice Extent in 2010
Arctic sea ice reached an abnormal low in summer 2010. Declines like this have made it possible for a long-lost species of plankton to return to the North Atlantic.
CREDIT: National Oceanic and Atmospheric Administration (NOAA)

A single-celled alga that went extinct in the North Atlantic Ocean about 800,000 years ago has returned after drifting from the Pacific through the Arctic thanks to melting polar ice. And while its appearance marks the first trans-Arctic migration in modern times, scientists say it signals something potentially bigger.

“It is an indicator of rapid change and what might come if the Arctic continues to melt,” said Chris Reid, a professor of oceanography at the Sir Alister Hardy Foundation for Ocean Science in the United Kingdom.

Arctic sea ice has been in decline for roughly three decades, and in several more recent summers, a passage has opened up between the Pacific and Atlantic. In as little as 30 years, Arctic summers are projected to Read more…

Polar bear’s long swim illustrates ice melt

February 3, 2011 Comments off

Searching for food, one female bear was tracked as she swam for 9 days across the Beaufort Sea before reaching an ice floe. Litigation continues over protection of bear habitat.

In one of the most dramatic signs ever documented of how shrinking Arctic sea ice impacts polar bears, researchers at the U.S. Geological Survey in Alaska have tracked a female bear that swam nine days across the deep, frigid Beaufort Sea before reaching an ice floe 426 miles offshore.

The marathon swim came at a cost: With little food likely available once she arrived, the bear lost 22% of her body weight and her year-old female cub, who set off on the journey but did not survive, the researchers said.

“Our activity data suggests that she swam constantly for nine days, without any rest. Which is pretty incredible,” said George M. Durner, a USGS zoologist and a lead author of the study, published last month in the journal Polar Biology.

“We have observed other long-distance swimming events. I don’t believe any of them have been Read more…