Linking African Easterly Wave Activity with Equatorial Waves and the Influence of Rossby Waves from the Southern Hemisphere

作者: Gui-Ying Yang , John Methven , Steve Woolnough , Kevin Hodges , Brian Hoskins

DOI: 10.1175/JAS-D-17-0184.1

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摘要: AbstractA connection is found between African easterly waves (AEWs), equatorial westward-moving mixed Rossby–gravity (WMRG) waves, and equivalent barotropic Rossby (RWs) from the Southern Hemisphere (SH). The amplitude phase of calculated by projection broadband-filtered ERA-Interim data onto a horizontal structure basis obtained wave theory. Mechanisms enabling interaction types are identified. AEWs dominated vorticity that tilts eastward below jet westward above: tilt necessary for baroclinic growth. However, strong relationship identified amplifying centers within WMRG waves. Although do not lock, positive amplify whenever cross-equatorial motion lies at same longitude in upper troposphere (southward flow) east this lower (northward flow). Two mechanisms could ...

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