 |
| Titel |
Tropospheric forcing of the boreal polar vortex splitting in January 2003 |
| VerfasserIn |
D. H. W. Peters, P. Vargin, A. Gabriel, N. Tsvetkova, V. Yushkov |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 28, no. 11 ; Nr. 28, no. 11 (2010-11-26), S.2133-2148 |
| Datensatznummer |
250016918
|
| Publikation (Nr.) |
 copernicus.org/angeo-28-2133-2010.pdf |
|
|
|
|
|
| Zusammenfassung |
The dynamical evolution of the relatively warm stratospheric winter season
2002–2003 in the Northern Hemisphere was studied and compared with the cold
winter 2004–2005 based on NCEP-Reanalyses. Record low temperatures were
observed in the lower and middle stratosphere over the Arctic region only at
the beginning of the 2002–2003 winter. Six sudden stratospheric warming
events, including the major warming event with a splitting of the polar
vortex in mid-January 2003, have been identified. This led to a very high
vacillation of the zonal mean circulation and a weakening of the
stratospheric polar vortex over the whole winter season. An estimate of the
mean chemical ozone destruction inside the polar vortex showed a total ozone
loss of about 45 DU in winter 2002–2003; that is about 2.5 times smaller than
in winter 2004–2005.
Embedded in a winter with high wave activity, we found two subtropical
Rossby wave trains in the troposphere before the major sudden stratospheric
warming event in January 2003. These Rossby waves propagated north-eastwards
and maintained two upper tropospheric anticyclones. At the same time, the
amplification of an upward propagating planetary wave 2 in the upper
troposphere and lower stratosphere was observed, which could be caused
primarily by those two wave trains. Furthermore, two extratropical Rossby
wave trains over the North Pacific Ocean and North America were identified a
couple of days later, which contribute mainly to the vertical planetary wave
activity flux just before and during the major warming event. It is shown
that these different tropospheric forcing processes caused the major warming
event and contributed to the splitting of the polar vortex. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|