On the age of stratospheric air and ozone depletion potentials in polar regions
- National Center for Atmospheric Research, Boulder, CO (United States)
- NASA Ames Research Center, Moffett Field, CA (United States)
- Univ. of Colorado, Boulder, CO (United States)
- Aeronomy Lab., Boulder, CO (United States)
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, CH{sub 3}Br, 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 CH{sub 3}Br and the Halons considered here confirm that they are rapidly dissociated within the stratosphere, with important implications for their ozone depletion potentials. 20 refs., 4 figs., 3 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 68036
- Journal Information:
- Journal of Geophysical Research, Vol. 97, Issue D12; Other Information: PBD: 20 Aug 1992
- Country of Publication:
- United States
- Language:
- English
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