Printer Friendly

Signs of early ozone loss.

Researchers monitoring ozone levels over the South Pole report signs that the ozone hole may have started developing earlier than usual this year.

Balloon-borne sensors measured ozone values as low as 195 Dobson units during the second week of September, 1 week earlier than usual, says Samuel J. Oltmans of the National Oceanic and Atmospheric Administration in Boulder, Colo. He adds that the timing of the ozone depletion does not necessarily mean that this year's hole will be more severe than previous ones.

The ozone hole opens in September when sunlight returns to the extreme south, energizing reactions in which chlorine pollution breaks down ozone molecules in the lower stratosphere--between about 12 and 23 kilometers in altitude. The depletion progresses until early October, when warm winds invade the region and shut down the cycle of chemical destruction.

Although the balloon measurements hint that the hole might be opening early this year, these sensors probe only the region directly over the pole and cannot track the development of the entire hole. Indeed, satellite observations over a broad region show the hole forming essentially on schedule, says Arlin J. Krueger of NASA's Goddard Space Flight Center in Greenbelt, Md.
COPYRIGHT 1991 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1991, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Antarctic ozone hole
Publication:Science News
Date:Sep 28, 1991
Previous Article:Sizing up atoms with electron holograms.
Next Article:Fibers with flare.

Related Articles
One ozone hole returns, another is found.
Antarctic ozone hole unexpectedly severe.
Depleted ring around ozone hole.
Antarctic ozone hole returns with a bang.
UV pours through ozone hole.
Summer ozone loss detected for first time.
Satellite spots prelude to ozone hole.
Northern hemisphere ozone hits record low.
Tracking ozone: life before the hole.
Ozone hole starts strong, fades quickly.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters