Phase speed spectra and the recent poleward shift of Southern Hemisphere surface westerlies

2007/11/01 by Gang Chen, Isaac M. Held · 1 citation
Earth and Planetary Sciences · Environmental Science · #Atmosphere (unit) #Atmospheric Ozone and Climate #Atmospheric and Environmental Gas Dynamics #Atmospheric circulation #Atmospheric sciences #Climate variability and models #Climatology #Eddy #Geology #Meteorology #Northern Hemisphere #Physics #Southern Hemisphere #Subtropics #Troposphere #Turbulence #Westerlies

paper · doi:10.1029/2007gl031200

openalex publication_date 2007/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06

Abstract

The poleward shift of the Southern Hemisphere surface westerlies in recent decades is examined in reanalysis data and in the output of coupled atmosphere‐ocean and uncoupled atmospheric models. The space‐time spectra of the eddy momentum fluxes in the upper troposphere reveal a trend that marks an increase in the eastward phase speed of the tropospheric eddies accompanied by a poleward displacement of the region of wave breaking in the subtropics. A dynamical mechanism is suggested that may help explain the connections among the lower stratospheric wind anomalies, the increased eastward propagation of tropospheric eddies and the poleward shift of the tropospheric circulation.

Citations

• GFDL's CM2 Global Coupled Climate Models. Part I: Formulation and Simulation Characteristics
• The ERA‐40 re‐analysis

Cited by

• Isaac Held [wikipedia]

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