The Structure and Bifurcation of Atmospheric Motions  

作　　者：刘式适 刘式达 付遵涛 辛国君 梁福明 

机构地区：[1]School of Physics, Peking University, Beijing 100871 [2]School of Physics, Peking University, Beijing 100871 State Key Laboratory for Turbulence and Complex Systems, Peking University, Beijing 100871 [3]School of Physics, Peking University, Beijing 100871he 3-D spiral structure resulting from the balance between the pressure gradient force, Coriolis force, and viscous force is a common atmospheric motion pattern. If the nonlinear advective terms are considered, this typical pattern can be bifurcated. It is shown that the surface low pressure with convergent cyclonic vorticity and surface high pressure with divergent anticyclonic vorticity are all stable under certain conditions. The anomalous structure with convergent anticyclonic vorticity is always unstable. But the anomalous weak high pressure structure with convergent cyclonic vorticity can exist, and this denotes the cyclone's dying out.

出　　处：《Advances in Atmospheric Sciences》2004年第4期557-561,共5页大气科学进展（英文版）

基　　金：Many thanks are due to sup-port from the Ministry of Science and Technology of China through a special public welfare project under Grant No.2002DIB20070;from the National Natural Science Foundation of China(Grant No.40305006).

摘　　要： The 3-D spiral structure resulting from the balance between the pressure gradient force, Coriolis force, and viscous force is a common atmospheric motion pattern. If the nonlinear advective terms are considered, this typical pattern can be bifurcated. It is shown that the surface low pressure with convergent cyclonic vorticity and surface high pressure with divergent anticyclonic vorticity are all stable under certain conditions. The anomalous structure with convergent anticyclonic vorticity is always unstable. But the anomalous weak high pressure structure with convergent cyclonic vorticity can exist, and this denotes the cyclone’s dying out.The 3-D spiral structure resulting from the balance between the pressure gradient force, Coriolis force, and viscous force is a common atmospheric motion pattern. If the nonlinear advective terms are considered, this typical pattern can be bifurcated. It is shown that the surface low pressure with convergent cyclonic vorticity and surface high pressure with divergent anticyclonic vorticity are all stable under certain conditions. The anomalous structure with convergent anticyclonic vorticity is always unstable. But the anomalous weak high pressure structure with convergent cyclonic vorticity can exist, and this denotes the cyclone's dying out.

关 键 词：horizontal divergence vertical vorticity spiral structure BIFURCATION 

分 类 号：P432[天文地球—大气科学及气象学]