NASA images show shrinking ozone hole
Animation of the ozone hole over Antarctica from 1989 to 1999
October 1, 1999
Web posted at: 12:22 p.m. EDT (1622 GMT)
(CNN) -- The latest NASA images of the ozone layer shows that a hole in the atmospheric layer that protects Earth from the sun's harmful radiation is shrinking.
The hole remains huge, with images showing it covers 9.8 million square miles.
"That's very big," said Paul Newman, an atmospheric physicist at NASA's Goddard Space Flight Center. That area would just about cover the entire North American continent.
But it's still slightly smaller than last year.
Purple areas on images show where the ozone layer is thinnest, and one patch that color covers the entire Antarctic continent.
The ozone problem extends beyond Earth's poles. The upper atmospheric layer has thinned worldwide, allowing more of the sun's ultraviolet light to reach Earth. Ultraviolet rays have been linked to skin cancer and cataracts, and they pose risks to plants and marine life.
"So it affects the whole biological chain because UV radiation affects biological molecules," Newman said.
The thinning ozone was first confirmed in the 1980s. The culprit was CFCs, or chlorofluorocarbons, used in everything from aerosol sprays to refrigerators, scientists said.
Chlorine molecules from CFC's can ride high into the atmosphere and demolish the protective ozone.
"One CFC molecule can destroy literally thousands of ozone molecules," Newman said.
While scientists track the destruction, there is hope thanks to a series of international agreements, which led to the ban of CFC production.
While this year's ozone hole is smaller than last year's, scientists say it will be a while before the hole disappears completely -- 2060 at the earliest.
CNN Correspondent Ann Kellan contributed to this report.
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NASA - Total Ozone Mapping
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