GENERALIZED ENERGY CONSERVATION AND UNSTABLE PERTURBATION PROPERTY IN BAROTROPIC VORTEX  

作　　者：黄泓 张铭 

机构地区：[1]Laboratory of Atmospheric Circulation and Short-range Climatic Prediction, Meteorological College, P.L.A.University of Science and Engineering Nanjing 211101 China

出　　处：《Journal of Tropical Meteorology》2006年第1期55-58,共4页热带气象学报（英文版）

基　　金：Research on wave spectrum of Meso-beta-scale system and its application in severe weatherforecast, a project from National Natural Science Foundation of China (40575023)

摘　　要：Based on a barotropic vortex model, generalized energy-conserving equation was derived and twonecessary conditions of basic flow destabilization are gained. These conditions correspond to generalizedbarotropic instability and super speed instability. They are instabilities of vortex and gravity inertial waverespectively. In order to relate to practical situation, a barotropic vortex was analyzed, the basic flow of which issimilar to lower level basic wind field of tropical cyclones and the maximum wind radius of which is 500 km.The results show that generalized barotropic instability depending upon the radial gradient of relative vorticitycan appear in this vortex. It can be concluded that unstable vortex Rossby wave may appear in barotropic vortex.Based on a barotropic vortex model, generalized energy-conserving equation was derived and two necessary conditions of basic flow destabilization are gained. These conditions correspond to generalized barotropic instability and super speed instability. They are instabilities of vortex and gravity inertial wave respectively. In order to relate to practical situation, a barotropic vortex was analyzed, the basic flow of which is similar to lower level basic wind field of tropical cyclones and the maximum wind radius of which is 500 km. The results show that generalized barotropic instability depending upon the radial gradient of relative vorticity can appear in this vortex. It can be concluded that unstable vortex Rossby wave may appear in barotropic vortex.

关 键 词：INSTABILITY barotropic vortex Spiral bands generalized energy conservation vortex Rossby wave 

分 类 号：P433.1[天文地球—大气科学及气象学]