Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters  

作　　者：LIU Xiao ZHOU QiHou YUAN Wei XU JiYao 

机构地区：[1]State Key Laboratory of Space Weather,Center for Space Science and Applied Research,Chinese Academy of Sciences Beijing 100190,China [2]College of Mathematics and Information Science,Henan Normal University,Xinxiang 453007,China [3]School of Electrical Engineering,Zhengzhou University,Zhengzhou 450001,China [4]Electrical and Computer Engineering Department,Miami University,Oxford,Ohio,USA

出　　处：《Science China(Technological Sciences)》2012年第5期1251-1257,共7页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 40921063, 41004063, 41074109, 40890165, and 41174127);the National Important Basic Research Project (Grant No. 2011CB811405);the China Postdoctoral Science Foundation (Grant No. 20100470506);supported in part by the Specialized Research Fund;the Open Research Program of the State Key Laboratory of Space Weather;the National Science Foundation of Unites States grant-ATM-0633418 to Miami University

摘　　要：Because of the importance of gravity waves （GWs） in coupling different atmospheric regions, further studies are necessary to investigate the characteristics of GW propagation in a non-isothermal atmosphere. Using a nonlinear numerical model, we simulate the propagation of small amplitude GWs with various wavelengths in different non-isothermal atmospheres. Our re- sults show that the GW vertical wavelength undergoes sharp changes above the stratopause and mesopause region. Specifically for a GW with an initial vertical wavelength of 5 km, the seasonal background temperature structure difference at 50° latitude can cause the vertical wavelength to vary by -2 krn in the mesosphere and by as large as -4.5 km in the lower thermosphere. In addition, the GW paths exhibit great divergence in the height range of -65-110 kin. Our results also show that the variations of GW path, vertical wavelength and horizontal phase velocity are not synchronized in a non-isothermal atmosphere as in an isothermal atmosphere. Despite the fact that all GWs change their characteristics as they propagate upward in a non-isothermal atmosphere, the variations relative to the initial parameters at a reference height are similar for different initial vertical wavelengths. Our results indicate that the changing characteristics of a gravity wave in a non-isothermal atmosphere need to be considered when investigating the relationship of GWs at two different heights.

关 键 词：gravity wave non-isothermal atmosphere atmospheric coupling 

分 类 号：P421[天文地球—大气科学及气象学] TE985[石油与天然气工程—石油机械设备]