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Hitting opposite records at opposite poles While the Arctic sea ice extent hits record lows, the winter sea ice around Antarctica has expanded to the highest extent on record Alan Bailey Petroleum News
In what is perhaps one of this year’s more curious climatic features, while the summer Arctic sea ice extent has sunk a long way below the previous record set in 2007, the winter ice extent in the Antarctic has simultaneously reached an all-time high. According to the National Snow and Ice Data Center, or NSIDC, the winter maximum ice extent in the Antarctic, achieved on Sept. 26, was 7.51 million square miles, with the average extent in September being slightly higher than the previous record set in 2006.
However, before global warming skeptics start tweeting their “I told you so” messages, they might want to look into the reason for this apparent climatic anomaly.
According to Dr. Sharon Stammerjohn of the Colorado Institute of Arctic and Alpine Research the climate has been warming over much of the Antarctic, NSIDC says. But the Antarctic is still cold. And the persistent year-round cold conditions over Antarctica coupled with a cold stratosphere, thanks to a polar hole in the atmosphere’s ozone layer, have coupled with a generally warming climate to strengthen the circumpolar winds in the winter. These stronger winds have pushed the sea ice outwards and northwards, except in the area of the Antarctic Peninsula, thus increasing the area of ocean covered by ice.
Arctic winds Interestingly, changes in wind patterns may have contributed to this year’s exceptionally high summer sea ice loss in the Arctic according to a new study published recently in Geophysical Research Letters by a team of scientists led by the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Laboratory. According to this study a previous west-to-east, upper-level wind flow in the summer has changed to a more north-south undulating pattern in recent years. Essentially, since 2007 the summer winds have blown north through the Bering Strait, across the polar region and then south into the Atlantic Ocean. This new wind pattern moves warmer air into the Arctic while causing cold Arctic air to move south.
The changing route of the wind, apparently caused by changes in atmospheric pressure, likely contributed both to the melting of ice in the Arctic and changing weather conditions in Western Europe and North America, the researchers concluded. And, with more solar energy going into the Arctic Ocean, North America and Europe are likely to see a continuation of extreme weather events, the researchers say.
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