Dynamical connection between tropospheric blockings and stratospheric polar vortex
The dynamical connection between Northern Hemisphere blocking events and the variability of the stratospheric polar vortex strength is studied. The analysis is based on the composite time evolution of the energy of baroclinic planetary waves during regional blocking occurrence. During Euro-Atlantic...
| Autores: | , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2010 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/44115 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/44115 |
| Access Level: | acceso abierto |
| Palabra clave: | 52 Weather Regimes Warmings Events Astrofísica Astronomía (Física) Física atmosférica 2501 Ciencias de la Atmósfera |
| Sumario: | The dynamical connection between Northern Hemisphere blocking events and the variability of the stratospheric polar vortex strength is studied. The analysis is based on the composite time evolution of the energy of baroclinic planetary waves during regional blocking occurrence. During Euro-Atlantic blocking events, an in phase forcing of stationary zonal wavenumber 1 occurs. The enhanced wave amplitude is associated with a stratospheric polar vortex deceleration, which may result, at times, in Sudden Stratospheric Warming (SSW) events of displacement type. Pacific blocking composites reveal an in phase forcing of stationary zonal wavenumber 2. In most cases, the amplification of the wavenumber 2 does not reduce the vortex strength, being even accompanied by a mean vortex acceleration. However, if the amplification of wavenumber 2 is preceded by an amplification of wavenumber 1, the initial vortex deceleration forced by wavenumber 1 may be continued by wavenumber 2, and a SSW event of splitting type may occur. |
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