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Science 8 January 1993:
Vol. 259. no. 5092, pp. 194 - 199
DOI: 10.1126/science.259.5092.194
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Articles

Atmospheric Lifetimes of Long-Lived Halogenated Species

A. R. Ravishankara 1, S. Solomon 2, A. A. Turnipseed 2, and R. F. Warren 2

1 National Oceanic and Atmospheric Administration Aeronomy Laboratory, Boulder, CO 80303, and Cooperative Institute for Research in Environmental Science, University of Colorado, Boulder, CO 80309 Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309
2 National Oceanic and Atmospheric Administration Aeronomy Laboratory, Boulder, CO 80303, and Cooperative Institute for Research in Environmental Science, University of Colorado, Boulder, CO 80309. A. R. Ravishankara is also affiliated with the Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309

The atmospheric lifetimes of the fluorinated gases CF4, C2F6, c-C4F8, (CF3)2c-C4F6, C5F12, C6F14, C2F5Cl, C2F4C12, CF3Cl, and SF6 are of concern because of the effects that these long-lived compounds acting as greenhouse gases can have on global climate. The possible atmospheric loss processes of these gases were assessed by determining the rate coefficients for the reactions of these gases with O(1D), H, and OH and the absorption cross sections at 121.6 nanometers in the laboratory and using these data as input to a two-dimensional atmospheric model. The lifetimes of all the studied perfluoro compounds are >2000 years, and those of CF3Cl, CF3CF2Cl, and CF2ClCF2Cl are >300 years. If released into the atmosphere, these molecules will accumulate and their effects will persist for centuries or millennia.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
A Potent Greenhouse Gas Identified in the Atmosphere: SF5CF3.
W. T. Sturges, T. J. Wallington, M. D. Hurley, K. P. Shine, K. Sihra, A. Engel, D. E. Oram, S. A. Penkett, R. Mulvaney, and C. A. M. Brenninkmeijer (2000)
Science 289, 611-613
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