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Arctic sea ice rebounds in October, but stays well below average

October Arctic sea ice has been declining at a rate of about 7.1 percent per decade during the satellite era.

Warm air temps due to open water inhibits ice growth in some areas

By Summit Voice

FRISCO — Arctic sea ice expanded quickly in October, with coverage doubling from the record low level of mid-September. But because the ice dwindled to an all-time low level this summer, even the record rebound in October couldn’t boost the ice extent back into the average range, according to the latest update from the National Snow and Ice Data Center.

The average ice extent for October was 2.7 million square miles, the second lowest in the satellite record and about 89,000 square miles above the 2007 record low for October. The ice extent is about 884,000 square miles below the 1979 to 2000 average. Continue reading

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Climate: Arctic sea ice expanding, but impacts from record-low levels could still be felt the next few months

Antarctic sea ice extent remains above average

Antarctic sea ice has dwindled from a record-high extent in October but remains above average for this time of year. Bob Berwyn photo.

By Summit Voice

SUMMIT COUNTY — Although Arctic sea ice cover has grown quickly the past few weeks, the extent remained below the previous record low for a full 40 days before recently climbing back to near that 2007 level on Oct. 6.

According to the National Snow and Ice Data Center, sea ice extent had grown to about 2 million square miles as of Oct. 15, which is about 1.35 million square miles below the 1979 to 2000 mean. Ice extent is growing by about 38,600 square miles per day, expanding southward at the ice edge, as well as northward from the Arctic continental coasts

Despite the rapid growth of the sea ice extent in the past few weeks, vast areas of open water remain, resulting in a massive heat transfer from the ocean to the atmosphere, with potential impacts on atmospheric circulation in high latitudes, as the heat buildup over the Arctic changes pressure gradients in the region. Continue reading

Arctic sea ice tracks near record low in July

Arctic sea ice extent has been tracking near record low levels much of the summer.

Melting slowed down during second half of the month

By Summit Voice

SUMMIT COUNTY — Arctic sea continued to track at or near record low levels throughout July, as an early start to the melt season led to large areas of open water that speed up melting in adjacent ice areas.

As of July 23, satellite images showed areas of low sea ice concentration in the Beaufort and Chukchi seas, the Canadian Archipelago, the East Greenland Sea, and north of Siberia. In the Beaufort and Chukchi seas, according to the latest update from the National Snow and Ice Data Center.

During the first half of July, sea ice reached record-low levels numerous times, but melting slowed slightly during the second half of the month as storm systems brought cooler air to the region.

Large areas of open water (called polynyas) are being reported around areas of multiyear sea ice. Low ice concentrations mean a low surface albedo, allowing for more of the sun’s energy to be absorbed, melting even more sea ice. This makes the multiyear ice in the Beaufort and Chukchi seas vulnerable to melting out this summer, according to the NSIDC.

In parts of the Barents, Kara and Laptev seas, open water extends as far north as typically seen during September, at the end of the summer melt season. Sea ice extent is near normal in the Chukchi Sea and slightly above normal in the East Greenland Sea.

Polar bears: How far can they swim?

Scientists try to assess potential impact of shrinking sea ice

Some Polar bears in the Arctic can swim in excess of 200 miles, according to USGS research.

Scientists track Polar bears with by attaching GPS equipped collars to a sample population. These collars transmit data that help develop maps like this one that shows a swim of nearly 220 miles long. MAP COURTESY USGS.

By Bob Berwyn

SUMMIT COUNTY — Given the steady decline of sea ice in the Arctic and the status of polar bears as threatened under the Endangered Species Act, biologists are trying to understand how the top-level predators might respond to those changing conditions.

It’s important because some of the most recent studies link declining sea ice with dropping polar bear survival and reproduction rates in the Southern Beaufort Sea and around Hudson Bay.

“With the sea ice retreating earlier and coming back later, there’s less time for them to hunt in the spring, when put on their fat,” said Alaska-based U.S. Geological Survey researcher Anthony Pagano. “They end up in poor body condition,” Pagano said, adding that some of the studies suggest a downward trend in average body weight. Continue reading

Groups challenge EPA air quality permits to halt Arctic drilling

Lawsuit says Shell’s oil-drilling ship doesn’t comply with air quality regs

Environmental groups want to prevent industrial drilling operations in the Arctic Sea off the coast of Alaska. PHOTO COURTESY U.S. COAST GUARD.

By Summit Voice

SUMMIT COUNTY — Conservation groups are challenging proposed exploratory oil drilling the Arctic Sea at every step of the way, most recently with a lawsuit challenging an EPA air pollution permit for Shell’s proposed operations in the Beaufort and Chukchi seas.

The lawsuit filed in the 9th Circuit Court of Appeals last week claims the permits shouldn’t have been issued because Shell’s oil exploration ship, the Discoverer, doesn’t meet the latest Clean Air Act standards.

“As early as this summer, the Discoverer drillship and other ships in Shell’s fleet could be in the Chukchi Sea or Beaufort Sea of the Arctic Ocean drilling for oil in some of the harshest conditions on earth,” said Vera Pardee, an attorney with the Center. “Each year, Shell’s massive ships will churn out vast amounts of harmful pollution that will not only damage the Arctic’s fragile ecosystems but accelerate the climate change that’s robbing polar bears and walruses of the sea ice they need to survive.” Continue reading

Researchers track freshwater flows in Arctic

Pools of freshwater play key role in maintaining Arctic icepack

Scientists explore the link between large-scale hemispheric pressure shifts and the ebb and flow of Arctic sea ice.

Increasing freshwater on the US and Canadian side of the Arctic from 2005 to 2008 is balanced by decreasing freshwater on the Russian side, so that on average the Arctic did not have more freshwater. Here, blue represents maximum freshwater increases and the yellows and oranges represent maximum freshwater decreases. GRAPHIC COURTESY NASA JPL/UNIVERSITY OF WASHINGTON.

By Summit Voice

SUMMIT COUNTY — The more scientists study the Arctic, the more they find how factors other than just constantly warming temperatures affect the ebb and flow of sea ice in the region.

Recent studies show how the influx of fresh water from Siberian rivers is affected by large-scale shifts in northern hemisphere pressure gradients.

Under a decades-long shift in atmospheric pressure associated with the Arctic Oscillation, the water was diverted hundreds of miles to a completely different part of the ocean, leading to record-breaking amounts of freshwater accumulating in the Arctic’s Beaufort Sea. Continue reading

Shell’s Arctic oil drilling plan challenged with lawsuit

Native Alaskans, conservation groups go to court to block federal approval for Beaufort Sea oil exploration and development

Sunset over the Beaufort Sea. PHOTO COURTESY USGS.

By Summit Voice

SUMMIT COUNTY — Alaska natives, along with state and national environmental groups, said Friday they have filed a lawsuit in the 9th Circuit Court of Appeals to block new offshore oil drilling in the Beaufort Sea, off the north coast of Alaska.

After a short delay following last summer’s Deepwater Horizon oil disaster, federal regulators approved plans by Shell to start Arctic drilling as soon as 2012 — despite the fact that there is no good disaster response or cleanup plan in place. Several federal reports have also pointed out that there are big gaps in the environmental data needed to make an accurate assessment of potential impacts.

The Bureau of Ocean Energy Management, Regulation and Enforcement released an environmental assessment for the Beaufort Sea plan Aug. 4, concluding with a finding of no significant impact. Continue reading

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