Ozone layer faces record 40 pct loss over Arctic

By JOHN HEILPRIN, Associated Press – Tue Apr 5, 7:01 pm ET

GENEVA – The protective ozone layer in the Arctic that keeps out the sun's most damaging rays — ultraviolet radiation — has thinned about 40 percent this winter, a record drop, the U.N. weather agency said Tuesday.

The Arctic's damaged stratospheric ozone layer isn't the best known "ozone hole" — that would be Antarctica's, which forms when sunlight returns in spring there each year. But the Arctic's situation is due to similar causes: ozone-munching compounds in air pollutants that are chemically triggered by a combination of extremely cold temperatures and sunlight.