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| Titel |
Major Sudden Stratospheric Warming events and the north Atlantic eddy driven jet for 1958-2014 winters |
| VerfasserIn |
Waheed Iqbal, Abdel Hannachi, Toshihiko Hirooka |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250153398
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| Publikation (Nr.) |
 EGU/EGU2017-18371.pdf |
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| Zusammenfassung |
| The Sudden Stratospheric Warming (SSW) events are a clear manifestation of the two-way
coupling between troposphere and stratosphere. These events result in cold to very cold
weather conditions over Europe and North-east America. Here in this study, we explore the
relationship between the major SSW events and the north Atlantic eddy driven jet for
December-March (DJFM) season over the period 1958-2014. The Japanese Re-analysis data
(JRA-55) for the daily zonal wind averaged over 925-700 hPa and the vertical component
of Eliassen-Palm (EP) fluxes at 100 hPa associated with the zonal wave number
1,2 and 3, have been used for the analysis. There is a highly significant relation
between SSWs and the jet latitude variability of the north Atlantic eddy driven
jet. The composite analysis shows a poleward jet one week before the significant
SSW event whereas an equatorward jet for more than a week after a SSW event.
The higher deviation in wave number 2 EP fluxes compared to wave number 1,
for pre-SSW event is observed. A given higher wave activity from all the zonal
wave numbers correspond to higher probability of the northern mode of the jet.
Furthermore, an attempt has been made to explore the mechanism for the different
preferred states of the eddy driven jet and the wave activity in the stratosphere. |
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