A numerical study on nonlinear propagation and short-term variability of the migrating diurnal and semidiurnal tides  

作　　者：HUANG Chunming1,2, ZHANG Shaodong1,2 & YI Fan1,2 1. School of Electronic Information, Wuhan Universiy, Wuhan 430079, China 2. Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan University, Wuhan 430079, China 

出　　处：《Chinese Science Bulletin》2005年第17期1940-1948,共9页

基　　金：This work was jointly supported by the National Natural Science Foundation of China(Grant Nos.40336054 and 40274051);the Program for New Century Excellent Talents in University of China;the Opening Foundation of Education Ministry Key Labo-ratory of Geospace Environment and Geodesy in Wuhan University of China.

摘　　要：By using a three-dimensional fully nonlinear numerical model in spherical coordinates and taking the linear steady solutions of the migrating diurnal and semidi-urnal tides in January from the Global-Scale Wave Model (GSWM) as the initial values, we simulate the linear and nonlinear propagations of the migrating diurnal and semidi-urnal tides in the atmosphere from the ground to the lower thermosphere. A comparison of our simulations with the results of GSWM is also presented. The simulation results show that affected by the nonlinearity, the migrating diurnal and semidiurnal tides propagating in the middle and upper atmosphere exhibit evident short-term variability. The nonlinear interactions between the migrating tides and the background atmosphere can obviously alter the background wind and temperature fields, which suggests that the nonlin-ear propagations of the migrating diurnal and semidiurnal tides impact significantly on the transient dynamical and thermal structures of the background middle and upper at-mosphere and the nonlinear effect is an important cause of the difference between the results of GSWM and observa-tions.By using a three-dimensional fully nonlinear numerical model in spherical coordinates and taking the linear steady solutions of the migrating diurnal and semidiurnal tides in January from the Global-Scale Wave Model （GSWM） as the initial values, we simulate the linear and nonlinear propagations of the migrating diurnal and semidiurnal tides in the atmosphere from the ground to the lower thermosphere. A comparison of our simulations with the results of GSWM is also presented. The simulation results show that affected by the nonlinearity, the migrating diurnal and semidiurnal tides propagating in the middle and upper atmosphere exhibit evident short-term variability. The nonlinear interactions between the migrating tides and the background atmosphere can obviously alter the background wind and temperature fields, which suggests that the nonlinear propagations of the migrating diurnal and semidiurnal tides impact significantly on the transient dynamical and thermal structures of the background middle and upper atmosphere and the nonlinear effect is an important cause of the difference between the results of GSWM and observations.

关 键 词：大气 非线性传播 数学模型 可变性 温度场 

分 类 号：P433[天文地球—大气科学及气象学]