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| Titel |
A comparative study of the major sudden stratospheric warmings in the Arctic winters 2003/2004-2009/2010 |
| VerfasserIn |
J. Kuttippurath, G. Nikulin |
| 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. 17 ; Nr. 12, no. 17 (2012-09-10), S.8115-8129 |
| Datensatznummer |
250011437
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| Publikation (Nr.) |
 copernicus.org/acp-12-8115-2012.pdf |
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| Zusammenfassung |
| We present an analysis of the major sudden stratospheric warmings
(SSWs) in the Arctic winters 2003/04–2009/10. There were 6 major
SSWs (major warmings [MWs]) in 6 out of the 7 winters, in
which the MWs of 2003/04, 2005/06, and 2008/09 were in January and
those of 2006/07, 2007/08, and 2009/10 were in February. Although the
winter 2009/10 was relatively cold from mid-December to mid-January,
strong wave 1 activity led to a MW in early February, for which the
largest momentum flux among the winters was estimated at
60° N/10 hPa, about 450 m2 s−2. The
strongest MW, however, was observed in 2008/09 and the weakest in
2006/07. The MW in 2008/09 was triggered by intense wave 2 activity
and was a vortex split event. In contrast, strong wave 1 activity led to the MWs of other winters
and were vortex displacement events. Large amounts of Eliassen-Palm (EP) and wave 1/2 EP fluxes
(about 2–4 ×105 kg s−2) are estimated shortly
before the MWs at 100 hPa averaged over 45–75° N in all winters,
suggesting profound tropospheric forcing for the MWs. We observe
an increase in the occurrence of MWs (~1.1 MWs/winter) in
recent years (1998/99–2009/10), as there were 13 MWs in the 12 Arctic
winters, although the long-term average (1957/58–2009/10) of the
frequency stays around its historical value (~0.7 MWs/winter),
consistent with the findings of previous studies. An analysis of the chemical
ozone loss in the past 17 Arctic winters (1993/94–2009/10) suggests
that the loss is inversely proportional to the intensity and timing of MWs
in each winter, where early (December–January) MWs lead to minimal ozone
loss. Therefore, this high frequency of MWs in recent Arctic winters
has significant implications for stratospheric ozone trends in the northern
hemisphere. |
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