RT Journal Article
T1 Dynamical connection between tropospheric blockings and stratospheric polar vortex
A1 Castanheira, J. M.
A1 Barriopedro Cepero, David
AB 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.
PB American Geophysical Union
SN 0094-8276
YR 2010
FD 2010-07-14
LK https://hdl.handle.net/20.500.14352/44115
UL https://hdl.handle.net/20.500.14352/44115
LA eng
NO © 2010 by the American Geophysical Union.
DS Docta Complutense
RD 28 abr 2025