不稳定横波型扰动谱点分布的半圆定理  

A Semicircle Theorem on the Spectral Distribution in Transverse Instability Perturbation

作　　者：张铭[1] 张立凤[1] 

机构地区：[1]解放军理工大学气象学院,南京211101

出　　处：《大气科学》2002年第1期102-110,共9页Chinese Journal of Atmospheric Sciences

基　　金：国家重点基础研究发展规划项目G1998040907;国家自然科学基金资助项目49875008共同资助

摘　　要：作者在理论上对不稳定横波型扰动的谱点分布作了分析，得到了该不稳定扰动谱点分布的半圆定理，即谱点分布在复平面上以原点为圆心 以Ｒ０为半径的下半圆域上；并发现扰动的波长越短、模式层顶越高、静力稳定度参数的绝对值越大、基流的垂直切变越大、纬度越高则该半径就越大。The spectral distribution of the transverse instability perturbation is theoretically studied. A semicircle theorem on the spectral distribution in transverse instability perturbation is derived. The theorem reveals that this distribution is in the lower semicircle of complex plane with the centerend ra-dius R0. The results show that the shorter the wavelength, the higher the mode top and the latitude, the larger the vertical shear of basic flow and the absolute value of static stability parameter, the larger the radius.

关 键 词：横波型扰动 半圆定理 数学模型 斜压不稳定 谱点分布 

分 类 号：P433.2[天文地球—大气科学及气象学]