Study: Ozone restoration to have impact

New York -- U.S. scientists say restoration of the Earth's ozone layer during the 21st century may have a significant impact on the climate of the Southern Hemisphere.

The ozone layer in the lower stratosphere prevents harmful ultraviolet radiation from reaching the surface. Researchers have attributed the depletion of that layer to use of aerosols containing chlorofluorocarbons, or CFCs. With the phase out of CFC production in 1996, scientists say they now expect the ozone layer to be restored by the second half of this century.

The team of 10 scientists, led by Columbia University, analyzed results from a newer climate model that takes into account the expected restoration of the ozone layer. That model predicts winds in high latitudes of the Southern Hemisphere might decelerate, potentially reversing the direction of climate change in that hemisphere

"We were surprised to find that the closing of the ozone hole, which is expected to occur in the next 50 years or so, shows significant effects on the global climate," said Professor Lorenzo Polvani. "This is because stratospheric ozone has not been considered a major player in the climate system."

The study appeared in a recent issue of the journal Science.

Copyright 2008 by United Press International