Behavior of gravity waves with limited amplitude in the vicinity of critical layer  

作　　者：WU Shaoping & Yl FanWuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China Department of Radio Science and Technology, Wuhan University, Wuhan 430072, China Department of Physics, Huazhong Normal Univ 

出　　处：《Chinese Science Bulletin》2002年第18期1547-1550,共4页

基　　金：This work wassupported by the National Natural Science Foundation of China (Grant No. 49625407).

摘　　要：By using the FICE scheme, a numerical simulation of three-dimensional nonlinear propagation of gravity wave packet in a wind-stratified atmosphere is presented. The whole nonlinear propagation process of the gravity wave packet is shown; the propagation behavior of gravity waves in the vicinity of critical layer is analyzed. The results show that gravity waves encounter the critical layer when propagating in the fair winds whose velocities increase with height, and the height of critical layer propagating nonlinearly is lower than that expected by the linear gravity waves theory; the amplitudes of gravity waves increase with height as a whole before gravity waves encounter the critical layer, but the increasing extent is smaller than the result given by the linear theory of gravity waves, while the amplitudes of gravity waves reduce when gravity waves meet the critical layer; the energy of wave decreases with height, especially at the critical layer; the vertical wavelength reduces with the heightBy using the FICE scheme, a numerical simulation of three-dimensional nonlinear propagation of gravity wave packet in a wind-stratified atmosphere is presented. The whole nonlinear propagation process of the gravity wave packet is shown; the propagation behavior of gravity waves in the vicinity of critical layer is analyzed. The results show that gravity waves encounter the critical layer when propagating in the fair winds whose velocities increase with height, and the height of critical layer propagating nonlinearly is lower than that expected by the linear gravity waves theory; the amplitudes of gravity waves increase with height as a whole before gravity waves encounter the critical layer, but the increasing extent is smaller than the result given by the linear theory of gravity waves, while the amplitudes of gravity waves reduce when gravity waves meet the critical layer; the energy of wave decreases with height, especially at the critical layer; the vertical wavelength reduces with the height increasing, but it does not become zero.

关 键 词：GRAVITY WAVES CRITICAL LAYER FICE scheme simulation. 

分 类 号：P35[天文地球—空间物理学]