GENEVA — A hole in the ozone layer over Antarctica has
appeared earlier than usual in 2007, the United Nations weather agency said on
Tuesday.
The World Meteorological Organization (WMO) said it would not
be clear for several weeks whether the ozone hole, which is expected to continue
growing until early October, would be larger than its record size in 2006.
"It is still too early to give a definitive statement about
the development of this year’s ozone hole and the degree of ozone loss that will
occur. This will, to a large extent, depend on the meteorological conditions,"
the Geneva-based agency said.
The ozone layer shields the earth from damaging ultra-violet
rays that can cause skin cancer.
While use of ozone-depleting chlorofluorocarbons (CFCs) has
waned, the WMO said large amounts of chlorine and bromine remain in the
atmosphere and would likely keep causing holes in the protective layer for years
to come.
"Although ozone-depleting substances are now declining
slowly, there is no sign that the Antarctic ozone hole is getting smaller," it
said in a report.
The WMO and the UN Environment Program have said the ozone
layer would likely return to pre-1980 levels by 2049 over much of Europe, North
America, Asia, Australasia, Latin America and Africa. But in Antarctica, the
agencies said, ozone layer recovery would likely be delayed until 2065.
Geir Braathen, a senior scientific officer with the WMO’s atmospheric
research and environment program, said the ozone hole may reach the southern tip
of South America in 2007. – Reuters
