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| Titel |
Accelerating growth of HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane) in the atmosphere |
| VerfasserIn |
J. C. Laube, P. Martinerie, E. Witrant, T. Blunier, J. Schwander, C. A. M. Brenninkmeijer, T. J. Schuck, M. Bolder, T. Röckmann, C. Veen, H. Bönisch, A. Engel, G. P. Mills, M. J. Newland, D. E. Oram, C. E. Reeves, W. T. Sturges |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 10, no. 13 ; Nr. 10, no. 13 (2010-07-02), S.5903-5910 |
| Datensatznummer |
250008590
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| Publikation (Nr.) |
 copernicus.org/acp-10-5903-2010.pdf |
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| Zusammenfassung |
| We report the first measurements of 1,1,1,2,3,3,3-heptafluoropropane
(HFC-227ea), a substitute for ozone depleting compounds, in air samples
originating from remote regions of the atmosphere and present evidence for
its accelerating growth. Observed mixing ratios ranged from below 0.01 ppt
in deep firn air to 0.59 ppt in the current northern mid-latitudinal upper
troposphere. Firn air samples collected in Greenland were used to
reconstruct a history of atmospheric abundance. Year-on-year increases were
deduced, with acceleration in the growth rate from 0.029 ppt per year in
2000 to 0.056 ppt per year in 2007. Upper tropospheric air samples provide
evidence for a continuing growth until late 2009. Furthermore we calculated
a stratospheric lifetime of 370 years from measurements of air samples
collected on board high altitude aircraft and balloons. Emission estimates
were determined from the reconstructed atmospheric trend and suggest that
current "bottom-up" estimates of global emissions for 2005 are too high by a
factor of three. |
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