Rossby wavepacket propagation in a zonally-varying basic flow

Takeshi Enomoto; Yoshihisa Matsuda

doi:10.3402/tellusa.v51i5.14477

Rossby wavepacket propagation in a zonally-varying basic flow

Tellus

Volume 51 (1999): Issue 5

By: Takeshi Enomoto and Yoshihisa Matsuda

Open Access

|Jan 1999

Abstract

Rossby wavepacket propagation in a zonally-varying basic flow is examined with a barotropic model in connection with the critical layer. A number of experiments are conducted by systematically changing the longitude of forcing, to analyze interactions between the zonally-varying flow and a Rossby-wave packet. A particular form of wave-activity flux applicable to zonally varying basic flows is used to illustrate the propagation patterns. Several reflection patterns are found and their mechanism, which is different from those currently proposed, is discussed. The present numerical results show that the wavepacket propagation slows down in the weak windregion and that vorticity anomalies are advected by the anticyclonic basic flow. Vorticity anomalies associated with Rossby waves, in turn, influence the intensity of a subtropical anticyclonic flow in the basic state. The present numerical results are compared with an observed vorticity overturning in the upper troposphere and wave amplification near the jet exit region obtained in a linear numerical study.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusa.v51i5.14477 | Journal eISSN: 3035-9554

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Language: English

Page range: 588 - 602

Submitted on: Sep 15, 1998

Accepted on: May 10, 1999

Published on: Jan 1, 1999

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 1999 Takeshi Enomoto, Yoshihisa Matsuda, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 51 (1999): Issue 5