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

	Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters
	Liu Xiao; Zhou QiHou; Yuan Wei; Xu JiYao
刊名	SCIENCE CHINA-TECHNOLOGICAL SCIENCES
	2012
卷号	55 期号:5 页码:1251-1257
关键词	gravity wave non-isothermal atmosphere atmospheric coupling
ISSN号	1674-7321
通讯作者	Liu, X (reprint author), Chinese Acad Sci, Ctr Space Sci & Appl Res, State Key Lab Space Weather, Beijing 100190, Peoples R China.
中文摘要	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 results 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 degrees latitude can cause the vertical wavelength to vary by similar to 2 km in the mesosphere and by as large as similar to 4.5 km in the lower thermosphere. In addition, the GW paths exhibit great divergence in the height range of similar to 65-110 km. 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.
英文摘要	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 results 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 degrees latitude can cause the vertical wavelength to vary by similar to 2 km in the mesosphere and by as large as similar to 4.5 km in the lower thermosphere. In addition, the GW paths exhibit great divergence in the height range of similar to 65-110 km. 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.
学科主题	空间物理
收录类别	SCI ; EI
资助信息	National Natural Science Foundation of China [40921063, 41004063, 41074109, 40890165, 41174127]; National Important Basic Research Project [2011CB811405]; China Postdoctoral Science Foundation [20100470506]; State Key Laboratory of Space Weather; National Science Foundation of Unites States [ATM-0633418]
语种	英语
公开日期	2014-12-15
内容类型	期刊论文
源URL	[http://ir.nssc.ac.cn/handle/122/3216]
专题	国家空间科学中心_空间科学部
推荐引用方式 GB/T 7714	Liu Xiao,Zhou QiHou,Yuan Wei,et al. Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters[J]. SCIENCE CHINA-TECHNOLOGICAL SCIENCES,2012,55(5):1251-1257.
APA	Liu Xiao,Zhou QiHou,Yuan Wei,&Xu JiYao.(2012).Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters.SCIENCE CHINA-TECHNOLOGICAL SCIENCES,55(5),1251-1257.
MLA	Liu Xiao,et al."Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters".SCIENCE CHINA-TECHNOLOGICAL SCIENCES 55.5(2012):1251-1257.