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To: Dealer who wrote (32380)9/8/2000 1:43:14 PM
From: T L Comiskey  Read Replies (1) | Respond to of 35685
 
Meanwhile...Nero looks for his fiddle............

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Friday, Sept. 8, 2000

NASA Spies Largest-Ever Antarctic Ozone Hole

WASHINGTON (Reuters) - The largest ozone hole ever observed
has opened up over Antarctica, a sign that ozone-depleting
gases churned out years ago are just now taking their greatest
toll, NASA scientists reported on Friday.

This year's South Pole ozone hole spreads over about 11
million square miles, an area three times larger than the land
mass of the United States.

Seen in an image released by the National Aeronautics and
Space Administration, the hole appears as a giant blue blob,
totally covering Antarctica and stretching to the southern tip
of South America.

The last time the ozone hole was close to this size was in
1998, when it spread over about 10.5 million square miles, NASA
said.

Paul Newman, who works with NASA's Total Ozone Mapping
Spectrometer (TOMS) instrument aboard a NASA satellite, said
ozone-watchers had expected a big hole this year, but not this
big.

``We expect to see the ozone hole every single year; we'll
be very old people when we actually see the ozone hole
disappear,'' Newman said in a telephone interview from NASA's
Goddard Space Flight Center outside Washington.

``What's unexpected is how big it is this year. ... We
expect some variation from year to year, but it's really
started early and it's considerably larger than we expected
it.''

The Antarctic ozone hole, first spotted in 1985, is caused
by the depletion of Earth-shielding ozone by human-made
chemicals such as chloroflurocarbons, known as CFCs.

Even though these chemicals were banned beginning in 1987,
they still remain in the atmosphere and will continue to do so
for years, Newman said.

``The peak vulnerability didn't occur right when they banned
CFCs,'' he said. ``It's the period of seven to 15 or 20 years
afterwards. ... Then things will slowly return to normal, but
that's going to be a long time.''

The peak years for the ozone hole's gigantic phase will
continue until 2010 or so, Newman said.

Ozone molecules, made up of three oxygen atoms, make up the
thin layer of the atmosphere that absorbs harmful ultraviolet
radiation from the Sun. The southern thinning of the ozone
layer over Antarctica has opened up into a hole for the last 15
years, with the hole at its largest in September and October.

This year's monster hole may have been caused by a change
in a swirling high-level air current over Antarctica, a sort of
polar jet stream that circles the area and contains the ozone
hole, Newman said.

The 2000 version of this air current extends farther north
than it has in the past.

``The containment is bigger, so the ozone hole is bigger,''

Newman said. ``We're not really sure why that happened.''

It probably had nothing to do with perceptions in the
United States of unusual weather this year, with
cooler-than-usual temperatures in the northeast and
higher-than-usual temperatures in the south and west, Newman
said.