WASHINGTON -- The news from the ozone front was grim.
The highest levels of ozone-destroying chemicals ever measured were found in the skies over Maine and eastern Canada last month, a team of scientists announced yesterday.
Alarmingly high levels of these same chemicals were also detected over London, Moscow, Berlin, Germany and other major cities in Europe and Asia.
And a hole in the ozone layer is virtually certain to form over the upper reaches of the Northern Hemisphere during the next decade.
It is possible that one will even form this winter, the scientists predicted.
"People should be alarmed by these latest findings," said Michael J. Kurylo, manager of NASA's Upper Atmosphere Research Program.
Scientists are concerned about the loss of ozone because increased ultraviolet rays could cause tens of millions of cases of skin cancer, cataracts and immune system diseases in the coming decades. The radiation has also been shown to damage crops such as soybeans and rice, harm trees, and disrupt tiny marine organisms that serve as food for many species of fish.
Since the 1970s, the planet's ozone has been thinning because of the release of man-made chemicals, such as chlorofluorocarbons and halons, into the atmosphere.
In 1985, a huge hole in the ozone layer was discovered over Antarctica, and each September it has formed again.
A hole over the Northern Hemisphere, home to most of the world's population, would be further evidence of destruction of the ozone layer -- the gaseous shield 10 to 35 miles above Earth. This layer blocks destructive amounts of ultraviolet radiation from reaching the planet's surface.