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| Titel |
Model simulations of stratospheric ozone loss caused by enhanced mesospheric NOx during Arctic Winter 2003/2004 |
| VerfasserIn |
B. Vogel, P. Konopka, J.-U. Grooß, R. Müller, B. Funke, M. López-Puertas, T. Reddmann, G. Stiller, T. Clarmann, M. Riese |
| 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 ; 8, no. 17 ; Nr. 8, no. 17 (2008-09-05), S.5279-5293 |
| Datensatznummer |
250006364
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| Publikation (Nr.) |
 copernicus.org/acp-8-5279-2008.pdf |
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| Zusammenfassung |
| Satellite observations show that the enormous solar
proton events (SPEs) in October–November 2003 had significant effects
on the composition of the stratosphere and mesosphere in the polar
regions. After the October–November 2003 SPEs and in early 2004,
significant enhancements of NOx(=NO+NO2) in the
upper stratosphere and lower mesosphere in the Northern Hemisphere
were observed by several satellite instruments. Here we present global
full chemistry calculations performed with the CLaMS model to study
the impact of mesospheric NOx intrusions on Arctic polar
ozone loss processes in the stratosphere. Several model simulations
are preformed with different upper boundary conditions for NOx at 2000 K potential temperature (≈50 km altitude). In
our study we focus on the impact of the non-local production of
NOx, which means the downward transport of enhanced NOx from the mesosphere to the stratosphere. The local production of
NOx in the stratosphere is neglected. Our findings show that
intrusions of mesospheric air into the stratosphere, transporting high
burdens of NOx, affect the composition of the Arctic polar
region down to about 400 K (≈17–18 km). We compare
our simulated NOx and O3 mixing ratios with satellite
observations by ACE-FTS and MIPAS processed at IMK/IAA and derive an
upper limit for the ozone loss caused by enhanced mesospheric NOx. Our findings show that in the Arctic polar vortex (equivalent
lat.>70° N) the accumulated column ozone loss between
350–2000 K potential temperature (≈14–50 km
altitude) caused by the SPEs in October–November 2003 in the
stratosphere is up to 3.3 DU with an upper limit of 5.5 DU until
end of November. Further, we found that about 10 DU, but in any case lower than
18 DU, accumulated ozone loss additionally occurred until end of March
2004 caused by the transport of mesospheric NOx-rich air in
early 2004. The solar-proton-produced NOx above 55 km due to
the SPEs of October–November 2003 had a negligibly small impact on
ozone loss processes through the end of November in the lower
stratosphere (350–700 K≈14–27 km). The mesospheric
NOx intrusions in early 2004 yielded a lower stratospheric
ozone loss of about 3.5 DU, and clearly lower than 6.5 DU through
the end of March. Overall, the non-local production of NOx is
an additional variability in the existing variations of the ozone loss
observed in the Arctic. |
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