Trajectory analysis of the propagation of Rossby waves on the Earth’s δ-surface

Jian Song,Hai-Le Xue,Chao-Jiu Da

doi:10.1080/16742834.2018.1506683

Abstract

The propagation of Rossby waves on the Earth’s δ-surface is discussed in a reference frame propagation with the zonal phase speed of the wave. In this reference frame, trajectories and streamlines ...

Highlights

Rossby waves are a fundamental wave motion in largescale atmospheric and oceanic dynamics, affecting weather and climate
We can draw the following main conclusions: The conservation equation of potential vorticity based on the δ-effect of Yang (1987, 1988) and Liu and Tan (1992) of Rossby waves cannot be ignored, especially in high-latitude regions, showing that the curvature of Earth is of great importance in the study of geophysical fluid dynamics
The propagation trajectory of barotropic and baroclinic Rossby waves is studied in a reference frame

Summary

Introduction

Rossby waves are a fundamental wave motion in largescale atmospheric and oceanic dynamics, affecting weather and climate. The propagation of Rossby waves is related to the variation in the Coriolis force with latitude, the so-called β-effect. Holton and Hakim (2012) showed the mechanism of Rossby wave propagation in a barotropic atmosphere. Song and Yang (2009, 2010) and Song et al (2009, 2017) have studied solitary Rossby waves in barotropic fluids and stratified fluids using the Wentzel-Kramers-Brillouin theory. In the barotropic and baroclinic model, Schneider (2015) analyzed the mechanism for the westward propagation of Rossby waves on the β-plane. Yang (1987, 1988) introduced the δ-surface approximation of the Earth’s surface by considering the second derivative of the Coriolis parameter with respect to latitude (the variation of β with the latitudinal δ-effect), revealing Rossby wave packet structural vacillation to exist in some basic currents or topographies on the Earth’s δsurface. The results show that the variation in β with the latitudinal δ-effect has an important influence on the propagation of Rossby waves

Barotropic Rossby waves on the Earth’s δ-surface

Baroclinic Rossby waves on the Earth’s δ-surface

Conclusions