气候变化领域集成服务门户(CCPortal): Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event

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DOI	10.5194/acp-20-7617-2020
	Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event
	Song I.-S.; Lee C.; Chun H.-Y.; Kim J.-H.; Jee G.; Song B.-G.; Bacmeister J.T.
发表日期	2020
ISSN	1680-7316
起始页码	7617
结束页码	7644
卷号	20 期号:12
英文摘要	Effects of realistic propagation of gravity waves (GWs) on distribution of GW pseudomomentum fluxes are explored using a global ray-tracing model for the 2009 sudden stratospheric warming (SSW) event. Four-dimensional (4D; x-z and t) and two-dimensional (2D; z and t) results are compared for various parameterized pseudomomentum fluxes. In ray-tracing equations, refraction due to horizontal wind shear and curvature effects are found important and comparable to one another in magnitude. In the 4D, westward pseudomomentum fluxes are enhanced in the upper troposphere and northern stratosphere due to refraction and curvature effects around fluctuating jet flows. In the northern polar upper mesosphere and lower thermosphere, eastward pseudomomentum fluxes are increased in the 4D. GWs are found to propagate more to the upper atmosphere in the 4D, since horizontal propagation and change in wave numbers due to refraction and curvature effects can make it more possible that GWs elude critical level filtering and saturation in the lower atmosphere. GW focusing effects occur around jet cores, and ray-tube effects appear where the polar stratospheric jets vary substantially in space and time. Enhancement of the structure of zonal wave number 2 in pseudomomentum fluxes in the middle stratosphere begins from the early stage of the SSW evolution. An increase in pseudomomentum fluxes in the upper atmosphere is present even after the onset in the 4D. Significantly enhanced pseudomomentum fluxes, when the polar vortex is disturbed, are related to GWs with small intrinsic group velocity (wave capture), and they would change nonlocally nearby large-scale vortex structures without substantially changing local mean flows. © Author(s) 2020.
语种	英语
scopus关键词	atmospheric dynamics; four-dimensional modeling; gravity wave; mesosphere; momentum; parameterization; polar vortex; ray tracing; sudden stratospheric warming; thermosphere; two-dimensional modeling; wave field; wave propagation
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/141245
作者单位	Division of Polar Climate Sciences, Korea Polar Research Institute, Incheon, South Korea; Department of Atmospheric Sciences, Yonsei University, Seoul, South Korea; Climate and Global Dynamics, National Center for Atmospheric Research, Boulder, CO, United States
推荐引用方式 GB/T 7714	Song I.-S.,Lee C.,Chun H.-Y.,et al. Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event[J],2020,20(12).
APA	Song I.-S..,Lee C..,Chun H.-Y..,Kim J.-H..,Jee G..,...&Bacmeister J.T..(2020).Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event.Atmospheric Chemistry and Physics,20(12).
MLA	Song I.-S.,et al."Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event".Atmospheric Chemistry and Physics 20.12(2020).