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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 97, NO. D12,
PAGES 12,993–12,999,
1992
On the Age Of Stratospheric Air and Ozone Depletion Potentials in Polar Regions
W. H. Pollock
National Center for Atmospheric Research, Boulder, Colorado
L. E. Heidt
National Center for Atmospheric Research, Boulder, Colorado
R. A. Lueb
National Center for Atmospheric Research, Boulder, Colorado
J. F. Vedder
NASA Ames Research Center, Moffett Field, California
M. J. Mills
Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado, Boulder, Colorado
S. Solomon
Aeronomy Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado
Abstract
Observations of the nearly inert, man-made chlorofluorocarbon CFC-115 obtained during January 1989 are used to infer the age
of air in the lower stratosphere. These observations together with estimated release rates suggest an average age of high-latitude
air at pressure altitudes near 17–21 km of about 3 to 5 years. This information is used together with direct measurements
of HCFC-22, HCFC-142b, CH3Br, H-1301, H-1211, and H-2402 to examine the fractional dissociation of these species within the Arctic polar lower stratosphere
compared to that of CFC-11 and hence to estimate their local ozone depletion potentials in this region. It is shown that these
HCFCs are much less efficiently dissociated within the stratosphere than CFC-11, lowering their ozone depletion potentials
to only about 30–40% of their chlorine loading potentials. In contrast, the observations of CH3Br and the Halons considered here confirm that they are rapidly dissociated within the stratosphere, with important implications
for their ozone depletion potentials.
Received 30
December
1991;
accepted 30
April
1992.
Subscriber Access to Full Article (Nonsubscribers may purchase for $9.00, Includes print PDF)
Citation: Pollock, W. H., L. E. Heidt, R. A. Lueb, J. F. Vedder, M. J. Mills, and S. Solomon
(1992),
On the Age Of Stratospheric Air and Ozone Depletion Potentials in Polar Regions,
J. Geophys. Res.,
97(D12),
12,993–12,999.
Copyright 1992 by the American Geophysical Union.
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