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 8, NUMBER 6, JUNE 1995

NEWS...
NORTHERN OZONE LOSS

Item #d95jun117

Europe and U.S. researchers observed record-breaking Arctic ozone depletion over the past winter and early spring, and substantial depletion over high northern midlatitudes outside the Arctic region.

Arctic depletion reached 50 percent in some thin layers, but typically ran 30-40 percent over extended areas. The losses are attributed to the combination of unusually low temperatures in March, which in the presence of sunlight drive chemical reactions between ozone and anthropogenic chlorine compounds. According to Neil Harris of the European Ozone Research Coordinating Unit in Cambridge, U.K., ice cloud particles, which provide a site for the reactions to occur, are becoming more common in the Arctic stratosphere. (See New Scientist, p. 7, Apr. 8 1995.) This trend has two causes—the Arctic stratosphere is becoming colder, and also the amount of water vapor is increasing—both of which are expected results of greenhouse warming.

In middle and high latitudes of the Northern Hemisphere outside the Arctic, ozone levels during the 1994-1995 winter were 10-20 percent lower, and in some areas up to 35 percent lower than values observed around 1980, before efforts to address ozone depletion began, according to the U.S. National Oceanic and Atmospheric Administration (NOAA). In contrast to the situation in the Arctic, however, scientists are not sure to what extent air circulation in the stratosphere accounts for the depletion, compared to any effect of chemical destruction. NOAA's Northern Hemisphere Winter Summary: 1994-95 is available from Alvin Miller at the NOAA Climate Prediction Center in Washington, D.C. (tel: 301 763 8071; fax: 301 763 8125). (Printed copies are limited; request information on electronic availability.)

See Nature, p. 487, Apr. 6; Chem. Eng. News, pp. 8-9, Apr. 10; Global Environ. Change Rep., pp. 4-5, Apr. 14; Science News, p. 277, May 6.