
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, October 19, 1993                   TAG: 9310190022
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A-2   EDITION: METRO 
SOURCE: Associated Press
DATELINE: WASHINGTON                                LENGTH: Short

OZONE LEVELS IN SKY LOWEST EVER

An unusually cold Antarctic winter and the continuing presence of chlorine in the atmosphere combined to produce the lowest levels ever of ozone over the Antarctic this year, scientists said Monday.

The ozone hole is not as large as last year's record-breaker, scientists said Monday. It covers 9 million square miles. In 1992, the hole was over 9.4 million square miles.

"The chlorine is there because of humans, but nature occasionally causes the Antarctic winter to be colder than others," said David J. Hoffman, senior scientist at the National Oceanic and Atmospheric Administration monitoring laboratory in Boulder, Colo.

"The phenomenon of converting manmade chlorine to forms which destroy the ozone is worse in some years," he said.

Ozone is a thin layer of the atmosphere that absorbs harmful ultraviolet radiation from the sun.

Hoffman said that as long as there is a combination of high chlorine concentrations and unusual cold, "you can expect to be setting new records every once in a while."

He said cold temperatures are probably the most important part of ozone depletion and that unusual cold caused an extension of the hole in an upward direction.

by CNB