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| Titel |
Chemical ozone loss and ozone mini-hole event during the Arctic winter 2010/2011 as observed by SCIAMACHY and GOME-2 |
| VerfasserIn |
R. Hommel, K.-U. Eichmann, J. Aschmann, K. Bramstedt, M. Weber, C. Savigny, A. Richter, A. Rozanov, F. Wittrock, F. Khosrawi, R. Bauer, J. P. Burrows |
| 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 ; 14, no. 7 ; Nr. 14, no. 7 (2014-04-02), S.3247-3276 |
| Datensatznummer |
250118558
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| Publikation (Nr.) |
 copernicus.org/acp-14-3247-2014.pdf |
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| Zusammenfassung |
| Record breaking loss of ozone (O3) in the Arctic stratosphere has
been reported in winter–spring 2010/2011. We examine in detail the
composition and transformations occurring in the Arctic polar vortex using
total column and vertical profile data products for O3, bromine oxide
(BrO), nitrogen dioxide (NO2), chlorine dioxide (OClO),
and polar stratospheric clouds (PSC) retrieved from measurements made by
SCIAMACHY (Scanning Imaging Absorption SpectroMeter for Atmospheric CHartography) on-board Envisat (Environmental Satellite), as well as total column ozone amount, retrieved
from the measurements of GOME-2 (Global Ozone Monitoring Experiment) on MetOp-A (Meteorological Experimental Satellite). Similarly we use
the retrieved data from DOAS (Differential Optical Absorption Spectroscopy) measurements made in Ny-Ålesund
(78.55° N, 11.55° E). A chemical transport model (CTM) has been
used to relate and compare Arctic winter–spring conditions in 2011 with those
in the previous year. In late winter–spring 2010/2011 the chemical ozone loss
in the polar vortex derived from SCIAMACHY observations confirms findings
reported elsewhere. More than 70% of O3 was depleted by halogen
catalytic cycles between the 425 and 525 K isentropic
surfaces, i.e. in the altitude range ~16–20 km. In
contrast, during the same period in the previous winter 2009/2010, a typical
warm Arctic winter, only slightly more than 20% depletion occurred below 20 km,
while 40% of O3 was removed above the 575 K isentrope
(~23 km). This loss above 575 K is explained by the catalytic destruction by NOx descending from the
mesosphere. In both Arctic winters 2009/2010 and 2010/2011, calculated O3
losses from the CTM are in good agreement to our observations and other model
studies. The mid-winter 2011 conditions, prior to the catalytic cycles being
fully effective, are also investigated. Surprisingly, a significant loss of
O3 around 60%, previously not discussed in detail, is observed in
mid-January 2011 below 500 K (~19 km) and
sustained for approximately 1 week. The low O3 region had an
exceptionally large spatial extent. The situation was caused by two
independently evolving tropopause elevations over the Asian continent.
Induced adiabatic cooling of the stratosphere favoured the formation of PSC,
increased the amount of active chlorine for a short time, and potentially
contributed to higher polar ozone loss later in spring. |
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