The wave geometry of final stratospheric warming events

Détails

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Etat: Public
Version: Final published version
Licence: CC BY 4.0
ID Serval
serval:BIB_99BAD7CACC04
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
The wave geometry of final stratospheric warming events
Périodique
Weather and Climate Dynamics
Auteur⸱e⸱s
Butler Amy H., Domeisen Daniela I. V.
ISSN
2698-4016
Statut éditorial
Publié
Date de publication
27/05/2021
Peer-reviewed
Oui
Volume
2
Numéro
2
Pages
453-474
Langue
anglais
Résumé
Every spring, the stratospheric polar vortex transitions from its westerly wintertime state to its easterly summertime state due to seasonal changes in incoming solar radiation, an event known as the “final stratospheric warming” (FSW). While FSWs tend to be less abrupt than reversals of the boreal polar vortex in midwinter, known as sudden stratospheric warming (SSW) events, their timing and characteristics can be significantly modulated by atmospheric planetary-scale waves. While SSWs are commonly classified according to their wave geometry, either by how the vortex evolves (whether the vortex displaces off the pole or splits into two vortices) or by the dominant wavenumber of the vortex just prior to the SSW (wave-1 vs. wave-2), little is known about the wave geometry of FSW events. We here show that FSW events for both hemispheres in most cases exhibit a clear wave geometry. Most FSWs can be classified into wave-1 or wave-2 events, but wave-3 also plays a significant role in both hemispheres. The timing and classification of the FSW are sensitive to which pressure level the FSW central date is defined, particularly in the Southern Hemisphere (SH) where trends in the FSW dates associated with ozone depletion and recovery are more evident at 50 than 10 hPa. However, regardless of which FSW definition is selected, we find the wave geometry of the FSW affects total column ozone anomalies in both hemispheres and tropospheric circulation over North America. In the Southern Hemisphere, the timing of the FSW is strongly linked to both total column ozone before the event and the tropospheric circulation after the event.
Open Access
Oui
Financement(s)
Fonds national suisse / PP00P2_170523
Création de la notice
08/03/2022 14:12
Dernière modification de la notice
09/07/2024 15:27
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