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Antarctic Ozone Hole Leveling Off
twistedfuck writes: "An Irish Time article reports that the size of the hole in the antartican ozone layer is levelling off and should begin reducing in size. It seems like it should be welcome news but it is tempered by the fact that more UV radiation will reach the southern hemisphere this year because the hole will persist longer. Unfortunately I can not find any details regarding the NOAA report on their website." Update: 11/06 17:31 GMT by H :Thanks to Isaac Lewis, NOAA Sysadmin and Slashdot reader, for pointing out more information, as well as pointing out the ozonelayer site.
Reduction in size of hole in ozone
Size of the annual hole which forms over the Antarctic has levelled off, say researchers.
Dick Ahlstrom reports
The ozone hole over the Antarctic this year is smaller than last year's but is still colossal. At 26 million square kilometres, it is about the size of North America.
The US National Oceanic and Atmospheric Administration said this week that observations suggested that the size of the annual hole, which forms over the Antarctic during its spring, has levelled off and will slowly decline in the coming years.
Researchers in New Zealand have warned, however that the 2001 hole will probably persist longer. This, they say, will allow more ultraviolet (UV) radiation to reach the earth in the southern hemisphere.
Too much UV disturbs the growth of plant life. It increases the risk of cataracts and skin cancer in humans.
The hole is caused after the release over many years of chlorine compounds that drifted into the upper atmosphere. There, they react with sunlight over the Antarctic and Arctic to destroy ozone, a gas which absorbs UV radiation coming from the sun.
Last year's hole reached a record 30 million square kilometres.
Repeated depletions over the years have reduced the total ozone overhead by about 15 per cent in temperate parts of the southern hemisphere.