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| Titel |
Global distributions of acetone in the upper troposphere from MIPAS spectra |
| VerfasserIn |
D. P. Moore, J. J. Remedios, A. M. Waterfall |
| 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 ; 12, no. 2 ; Nr. 12, no. 2 (2012-01-17), S.757-768 |
| Datensatznummer |
250010528
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| Publikation (Nr.) |
 copernicus.org/acp-12-757-2012.pdf |
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| Zusammenfassung |
| This study reports the first global measurements of acetone (C3H6O) in
the upper troposphere (UT). Profiles were obtained between 9 km and 15 km
from measurements made by the Michelson Interferometer for Passive
Atmospheric Sounding (MIPAS) onboard Envisat in August 2003. Errors per
profile are lower than 40 % between 180 hPa and 350 hPa. We report strong
hemispheric differences in the acetone volume mixing ratios (VMRs), with
average concentrations highest in the Northern Hemisphere (NH) mid-latitude
UT, between 1000 pptv and 1600 pptv with maxima up to 2300 pptv. Our
results show a strong enhancement of acetone relative to CO, particularly
over Europe (7 pptv ppbv−1), confirming aircraft studies. Ten-day
backward trajectories from these high European values show strong
contributions from air flows over North America (56 %) and 25 % from
Southernmost Asia. Enhanced acetone is also observed over Greenland, Siberia
and biomass burning regions of Africa. Zonal distributions show that acetone
VMRs decrease rapidly with increasing altitude (decreasing pressure),
particularly in the NH. Poleward of 45° S, acetone VMRs remain
fairly consistent with average VMRs between 400 pptv and 500 pptv. In 5-day
averages at 9 km, NH VMRs poleward of 45° N are consistently
higher than Southern Hemisphere observations poleward of 45° S, by
between 750 pptv and 1100 pptv. The results show a clear influence of
mid-latitude and transport processes on the acetone summertime distribution. |
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