NASA Spies Largest-Ever Antarctic Ozone Holegreenspun.com : LUSENET : TB2K spinoff uncensored : One Thread
Friday September 8 1:07 PM ET NASA Spies Largest-Ever Antarctic Ozone Hole
By Deborah Zabarenko
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.
-- (email@example.com), September 09, 2000
-- (firstname.lastname@example.org), September 09, 2000.
-- (email@example.com), September 09, 2000.
I was going to post this, but you beat me to it...
Oh well, life goes on. I guess we can use this to prove that cpr is once again WRONG about something. Isn't he one of those guys that says global warming isn't happening?
Yea, that's the ticket. We've got him on the run over oil prices, where he has been WRONG, WRONG, WRONG, and WRONG again for months. Let's add this fuel to the fire. Can you imagine cpr being WRONG on two things? OH MY GOD, we'll NEVER hear the end of it...
What a world... <:)=
-- Sysman (firstname.lastname@example.org), September 09, 2000.
At the rate it is going, looks like it will probably cover the yellow area in 10 years, and then the entire planet. Uh-oh, get some sunblock with SPF 1000!
-- (email@example.com), September 09, 2000.
"They" can fix it, though, that is, if it was neccesary, The link works.
-- If it's free (Ifirstname.lastname@example.org), September 09, 2000.
I guess it must be true.
We are all going to die.
(SOONER OR LATER).
-- cpr (email@example.com), September 09, 2000.