切变基流中β中尺度扰动的特征波动  

Characteristic Wave of Meso-β Scale Disturbance in Shear Basic Flow

作　　者：张立凤[1] 施连俊[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》2004年第4期589-600,共12页Chinese Journal of Atmospheric Sciences

基　　金：国家重点基础研究发展规划项目G1 9980 40 90 7资助

摘　　要：利用Bussinesq方程 ,通过数值计算的方法 ,讨论了中尺度扰动的特征波动 ,发现 β中尺度波动 (一对重力惯性波和一支涡旋波 )的波谱特征与背景场有关 ,在基流存在垂直切变的情况下 ,三支波动都存在连续谱。随着风切变的增大 ,连续谱发生重叠。在连续谱的重叠谱区 ,谱函数也发生了变化 ,即扰动结构发生了变化 ,这一点与α中尺度扰动的特征波动不同。The characteristic wave of meso-β scale disturbance is discussed using the means of numerical calculation by Bussinesq equations. The results show that the characteristic of wave spectrum of meso β scale waves is related to basic field. When having vertical shear in basic flow, a pair of gravitational inertial waves and a branch vortex wave all exist continuous spectrum. The continuous spectrums occur to overlap with the increase of wind shear. The spectral functions also change in the overlap spectrum area, namely the disturbance structure change. It is different from the characteristic wave of meso α scale disturbance.

关 键 词：β中尺度扰动 特征波动 连续谱 数值计算 旋波 重力惯性波 

分 类 号：P445[天文地球—大气科学及气象学]