|
Titel |
A tropospheric ozone maximum over the equatorial Southern Indian Ocean |
VerfasserIn |
L. Zhang, Q. B. Li, L. T. Murray, M. Luo, H. Liu, J. H. Jiang, Y. Mao, D. Chen, M. Gao, N. Livesey |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7316
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 12, no. 9 ; Nr. 12, no. 9 (2012-05-14), S.4279-4296 |
Datensatznummer |
250011134
|
Publikation (Nr.) |
copernicus.org/acp-12-4279-2012.pdf |
|
|
|
Zusammenfassung |
We examine the distribution of tropical tropospheric ozone (O3) from
the Microwave Limb Sounder (MLS) and the Tropospheric Emission Spectrometer
(TES) by using a global three-dimensional model of tropospheric chemistry
(GEOS-Chem). MLS and TES observations of tropospheric O3 during 2005 to
2009 reveal a distinct, persistent O3 maximum, both in mixing ratio and
tropospheric column, in May over the Equatorial Southern Indian Ocean
(ESIO). The maximum is most pronounced in 2006 and 2008 and less evident in
the other three years. This feature is also consistent with the total column
O3 observations from the Ozone Mapping Instrument (OMI) and the
Atmospheric Infrared Sounder (AIRS). Model results reproduce the observed
May O3 maximum and the associated interannual variability. The origin
of the maximum reflects a complex interplay of chemical and dynamic factors.
The O3 maximum is dominated by the O3 production driven by
lightning nitrogen oxides (NOx) emissions, which accounts for 62% of
the tropospheric column O3 in May 2006. We find the contribution from
biomass burning, soil, anthropogenic and biogenic sources to the O3
maximum are rather small. The O3 productions in the lightning outflow
from Central Africa and South America both peak in May and are directly
responsible for the O3 maximum over the western ESIO. The lightning
outflow from Equatorial Asia dominates over the eastern ESIO. The
interannual variability of the O3 maximum is driven largely by the
anomalous anti-cyclones over the southern Indian Ocean in May 2006 and
2008. The lightning outflow from Central Africa and South America is
effectively entrained by the anti-cyclones followed by northward transport
to the ESIO. |
|
|
Teil von |
|
|
|
|
|
|