低纬大气滤波模式研究

本文从描写低纬大气运动的方程组出发,采用半地转模式和准地转模式对低纬快速波动进行了滤除,这些模式仅含低频的Rossby波。分析指出:低纬半地转模式可以滤去高频波动,但得到的是波数k→0的Rossby波;而低纬准地转模式不但可以滤去高频波动,而且得到的是不受歪曲的Rossby波。 在滤波的基础上,本文分析了由Rossby波引起的低频振荡周期。 

AN INVESTIGATION OF FILTERED MODEL FOR THE TROPICAL ATMOSPHERE

A filtered model for the tropical atmosphere is investigated. Starting from the equations describing the atmosphere motion in the tropics and using the semi-geostrophic and quasi-geostrophic models high frequency waves are filtered leaving low frequency Rossby waves. It is shown that the semi-geostrophic approximation can filter the high frequency waves to have the Rossby waves with k-0. The quasi-geostrophic approximation can not only filter the high frequency waves but also obtain undistorted Rossby waves.On the basis of filtering, the low frequency oscillation caused by the Rossby waves is analyzed.