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 7, NUMBER 8, AUGUST 1994

PROFESSIONAL PUBLICATIONS... OF GENERAL INTEREST: OZONE DEPLETION

Item #d94Aug9

Two items from Geophys. Res. Lett., 21(17), Aug. 15, 1994:

"Recovery of Stratospheric Ozone over the United States in the Winter of 1993-1994," D.J. Hofmann (CMDL, NOAA, 325 Broadway, Boulder CO 80303), S.J. Oltmans et al., 1779-1782. Total ozone levels, which were 10-15% below normal over the U.S. during the winter of 1992-93, were slightly above normal during the winter of 1993-94. Measurements of aerosol particle surface area suggest that the Mt. Pinatubo eruption caused a temporary depletion of ozone through reactions with anthropogenic chlorine on particle surfaces. Since that eruption was small in comparison to historic eruptions, the potential for more severe reductions in ozone over populated areas will be present well into the 21st century.

"Ozone Variations Related to Volcanic Activity and Disappearance of SO2," V.C. Roldugin (Polar Geophys. Inst., Apatity, Murmansk Region, 184200, Russia), K. Henriksen, 1783-1786. Performed a trend analysis of total ozone data for three regions of the USSR for the period 1973-1989. The decreasing trends observed are almost entirely explained by volcanic eruptions and the influence of decreasing SO2 on ozone observations, leaving little or no evidence of ozone declines from anthropogenic activity.

Item #d94Aug10

"An Investigation into the Sensitivity of the Atmospheric Chlorine and Bromine Loading Using a Globally Averaged Mass Balance Model," D.C. Dowdell (Dept. Environ. Sci., Univ. Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK), G.P. Matthews, I. Wells, Atmos. Environ., 28(12), 1989-1999, July 1994.

Uses globally averaged mass balance models, which take into account how halocarbons are used and how each use delays their entrance to the atmosphere, to evaluate policy options regarding the elimination of ozone-depleting substances. Under Montreal Protocol 3, atmospheric chlorine will peak in 1994 but not return to pre-ozone-hole levels until 2053. The introduction of stringent policies for HCFC usage would reduce atmospheric chlorine in the first half of the next century, but would have a minimal effect on the latter date.