Stationary wave biases and their effect on upward troposphere– stratosphere coupling in sub-seasonal prediction models
Détails
Télécharger: wcd-3-679-2022.pdf (8199.28 [Ko])
Etat: Public
Version: Final published version
Licence: CC BY 4.0
Etat: Public
Version: Final published version
Licence: CC BY 4.0
ID Serval
serval:BIB_44C0BE276E02
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Stationary wave biases and their effect on upward troposphere– stratosphere coupling in sub-seasonal prediction models
Périodique
Weather and Climate Dynamics
ISSN
2698-4016
Statut éditorial
Publié
Date de publication
23/06/2022
Peer-reviewed
Oui
Volume
3
Numéro
2
Pages
679-692
Langue
anglais
Résumé
The simulated Northern Hemisphere winter stationary wave (SW) field is investigated in 11 Subseasonal-to-Seasonal (S2S) prediction project models. It is shown that while most models considered can well simulate the stationary wavenumbers 1 and 2 during the first 2 weeks of integration, they diverge from observations following week 3. Those models with a poor resolution in the stratosphere struggle to simulate the waves, in both the troposphere and the stratosphere, even during the first 2 weeks. Focusing on the tropospheric regions where SWs peak in amplitude reveals that the models generally do a better job in simulating the northwestern Pacific stationary trough, while certain models struggle to simulate the stationary ridges in both western North America and the North Atlantic. In addition, a strong relationship is found between regional biases in the stationary height field and model errors in simulated upward propagation of planetary waves into the stratosphere. In the stratosphere, biases are mostly in wave 2 in those models with high stratospheric resolution, whereas in those models with low resolution in the stratosphere, a wave 1 bias is evident, which leads to a strong bias in the stratospheric mean zonal circulation due to the predominance of wave 1 there. Finally, biases in both amplitude and location of mean tropical convection and the subsequent subtropical downwelling are identified as possible contributors to biases in the regional SW field in the troposphere.
Web of science
Site de l'éditeur
Open Access
Oui
Financement(s)
Fonds national suisse / PP00P2_170523
Fonds national suisse / PP00P2_198896
Création de la notice
05/09/2022 15:31
Dernière modification de la notice
10/07/2024 7:05