气候变化领域集成服务门户(CCPortal): A Simple Model of Convectively Coupled Equatorial Rossby Waves

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DOI	10.1029/2018MS001433
	A Simple Model of Convectively Coupled Equatorial Rossby Waves
	Fuchs-Stone Ž.; Raymond D.J.; Sentić S.
发表日期	2019
ISSN	19422466
起始页码	173
结束页码	184
卷号	11 期号:1
英文摘要	Intraseasonal oscillations affect the weather not just in the tropics but all around the globe. The convectively coupled equatorial Rossby wave is observed as the westward-moving intraseasonal oscillation. The fundamental physics of its coupling is still unknown; thus, many questions remain unanswered. How is its phase speed altered by convection? What makes it unstable? Why is it an intraseasonal oscillation? Using the Fuchs and Raymond model with linearized governing equations on an equatorial beta plane, first baroclinic mode vertical structure, and moisture and wind-induced surface heat exchange (WISHE) convective parametrizations, this paper seeks a fundamental analytical theory that can explain the basic features of the convectively coupled equatorial Rossby wave. The WISHE-moisture theory leads to a large-scale, unstable westward propagating mode in the n = 1 case, which we call the westward propagating WISHE-moisture mode. We find that the westward propagating WISHE-moisture mode is indeed the free equatorial Rossby wave in the absence of moisture closure and WISHE. It is propagating westward due to the beta effect, and it slows down when it is convectively coupled. Its phase speed decreases mainly due to WISHE and cloud-radiation interactions. The x-y structure of the pressure and horizontal winds is similar to the free and observed Rossby wave, with convergent net flow. The strongest easterlies are to the west of the precipitation maximum increasing the moisture in that area. The mode is unstable due to the interplay of surface fluxes and moisture, which increases as a function of zonal wavelength. © 2018. The Authors.
语种	英语
scopus关键词	Moisture; Tropical engineering; Analytical theory; Cloud-radiation interactions; Equatorial Rossby waves; Fundamental physics; Governing equations; Intraseasonal oscillations; Vertical structures; Wind induced surface heat exchange; Mechanical waves; atmospheric convection; atmospheric moisture; baroclinic mode; climate oscillation; equatorial wave; heat transfer; model; parameterization; Rossby wave; wave propagation
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156990
作者单位	Department of Physics, New Mexico Institute of Mining and Technology, Socorro, NM, United States; Climate and Water Center, New Mexico Institute of Mining and Technology, Socorro, NM, United States
推荐引用方式 GB/T 7714	Fuchs-Stone Ž.,Raymond D.J.,Sentić S.. A Simple Model of Convectively Coupled Equatorial Rossby Waves[J],2019,11(1).
APA	Fuchs-Stone Ž.,Raymond D.J.,&Sentić S..(2019).A Simple Model of Convectively Coupled Equatorial Rossby Waves.Journal of Advances in Modeling Earth Systems,11(1).
MLA	Fuchs-Stone Ž.,et al."A Simple Model of Convectively Coupled Equatorial Rossby Waves".Journal of Advances in Modeling Earth Systems 11.1(2019).