Antarctic ozone hole may be larger in 2008 - U.N.

GENEVA (Reuters) - The hole in the ozone layer over Antarctica may be larger this year than in 2007, the United Nations weather agency said on Friday.

The ozone layer shields the Earth from damaging ultra-violet rays that can cause skin cancer. The Antarctic ozone hole is normally about the size of North America but its ultimate size depends on weather conditions.

"As the sun returns to Antarctica after the polar night, it is expected that ozone depletion will speed up," the World Meteorological Organisation said in its latest Ozone Bulletin.

Satellite and other observations to date "could indicate that the 2008 ozone hole will be smaller than the 2006 ozone hole but larger than the one of 2007," the WMO said, noting this year's ozone depletion began "somewhat later than last year."

While use of ozone-depleting chlorofluorocarbons (CFCs) has waned, large amounts of chlorine and bromine remain in the atmosphere and cause recurrent holes in the protective layer.

"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," it added.