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Antarctic ozone
hole nears record: U.N. agency
GENEVA (Reuters) -
The hole over Antarctica's ozone layer is bigger than last year and is nearing
the record 29-million-square-km (11-million-sq-mile) hole seen in 2000, the
World Meteorological Organization said on Friday.
Geir Braathen, the United Nations
weather agency's top ozone expert, said ozone depletion had a late onset in this
year's southern hemisphere winter, when low temperatures normally trigger
chemical reactions that break down the atmospheric layer that filters dangerous
solar radiation.
"The ozone depletion started
quite late, but when it started it came quite rapidly," Braathen told
journalists in Geneva.
"It (the hole) has now risen
to a level that has passed last year's, and is very close to, if not equal to,
the ozone hole size of 2003, and also approaching the size of 2000," he
said.
The Antarctic ozone hole was at
its second-largest in 2003.
While use of ozone-depleting
chlorofluorocarbons (CFCs) has waned, Braathen said large amounts of chlorine
and bromine remain in the atmosphere and would keep causing large reductions in
the Antarctic ozone layer for many years to come.
"We will for the next couple
of decades expect to see recurring ozone holes of the size that we see
now," he said.
The WMO and the U.N. Environment
Program (UNEP) said in August that the protective layer would likely return to
pre-1980 levels by 2049 over much of Europe, North America, Asia, Australasia,
Latin America and Africa.
In Antarctica, the agencies said
ozone layer recovery would likely be delayed until 2065.
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