More Than Half the Ozone Over the Arctic Temporarily Destroyed |
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Written by spacetravel.org
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Saturday, 09 July 2005 22:31 |
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More than half the ozone over the Arctic was destroyed over the winter. However, data from NASAs Aura spacecraft show that other atmospheric processes have now restored ozone to near-average levels.
Scientists from the EUs SCOUT-13 project say that from November to February, the presence of large areas of polar stratospheric clouds dramatically changed the chemical balance of the Arctic region, altering the breakdown of products from manmade CFCs. This allowed ozone to be destroyed in sunlight. Very cold temperaturesthis was the coldest winter since 1955affected the distribution of nitrogen oxides, enabling ozone destruction to last longer than usual. Overall ozone losses were 30 percent, but in the altitude range where the ozone layer usually reaches maximum concentration, over 50 percent of the ozone was destroyed.
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