A rchive Date
[ 08-09-2000 ]
Category
[ International Relations ]
sub-Categoy
[ Ecology ]
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[U.N.: Antarctic ozone depleting
By YURI BAGROV -- The Associated Press
Friday, September 8, 2000
GENEVA (AP) -- The hole in the ozone layer over the Antarctic is opening up, with ozone depletion rates that are unprecedented for this time of year, the U.N. weather agency said Friday.
Ozone depletion in the region starts in July and intensifies during August. In recent days, observation stations in the Antarctic have been reporting total decreases in ozone of between 10 and 50 percent compared with the period between 1964 and 1976, before the "ozone hole" was observed, the World Meteorological Organization said.
Decreases of 50 percent "are common during each ozone hole season," the WMO ozone bulletin said. But "it is remarkable to find these low values so early in September, perhaps one or two weeks earlier than in any previous year."
"We're expecting very large depletion during the next couple of weeks," WMO spokesman Taysir al-Ghanem said.
Reduction of the protective ozone layer can let damaging ultraviolet rays from the sun reach the earth's surface. Too much UV radiation can cause skin cancer and destroy tiny plants at the beginning of the food chain.
WMO says the biggest hole yet in the ozone layer was recorded in 1998, when it reached some 4.63 million square miles, partly helped by strong winds in the upper atmosphere. Last year, the hole reached some 3.86 million square miles. WMO did not give an estimate of the size of this year's hole.
One cause of ozone depletion is chlorine and bromine released by manmade chemical compounds such as chlorofluorocarbons, contained in some aerosols. WMO says those chemicals have leveled off thanks to the Montreal Protocol, which commits countries to eliminating production and use of ozone-depleting substances.
But the agency says it could be 20 years before ozone levels recover noticeably. Full recovery can be expected around 2050.
 World Fact Book (CIA)]
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