Last Updated:
February 28, 2007

GCRIO Program Overview

Library 
Our extensive collection of documents.

Privacy Policy

Archives of the
Global Climate Change Digest
A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999

FROM VOLUME 10, NUMBER 5, MAY 1997

NEWS...
ARCTIC OZONE

Item #d97may93

Arctic ozone levels during late March 1997 were the lowest ever measured there by the satellite-borne Total Ozone Mapping Spectrometer (TOMS), according to NASA scientists. The 1996-1997 polar stratospheric vortex was unusually strong and persistent, providing the cold temperatures necessary to form polar stratospheric cloud particles, a key factor in ozone destruction by anthropogenic chlorine. This year the vortex was centered on the pole; last winter it had shifted toward the North Atlantic, closer to populated areas.

Although this year's levels were twice as high as the lowest measured over Antarctica, some scientists are concerned about the low winter temperatures that have persisted late in the season for the past several years and have contributed to ozone loss. They are beginning to consider whether the winter temperatures could be driven by some mechanism related to ozone depletion or greenhouse gases. (See New Scientist, p. 13, Apr. 19, 1997, and feature article in Global Environ. Change Rep., pp. 1-3, Apr. 11.)