气候变化领域集成服务门户(CCPortal): Easterly wave contributions to seasonal rainfall over the tropical Americas in observations and a regional climate model

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DOI	10.1007/s00382-019-04996-7
	Easterly wave contributions to seasonal rainfall over the tropical Americas in observations and a regional climate model
	Dominguez C.; Done J.M.; Bruyère C.L.
发表日期	2020
ISSN	0930-7575
起始页码	191
结束页码	209
卷号	54 期号:2020-01-02
英文摘要	Easterly waves (EWs) are important moisture carriers and their variability can impact the total May–November rainfall, defined as seasonal precipitation, over the Tropical Americas. The contribution of EWs to the seasonal precipitation is explored over the tropical Americas using rain gauge stations, reanalysis data and a regional model ensemble during the 1980–2013 period. In the present study, EWs are found to produce up to 50% of seasonal rainfall mainly over the north of South America and contribute substantially to interannual regional rainfall variability. An observational analysis shows that the El Niño Southern Oscillation (ENSO) affects EW frequency and therefore, their contribution to seasonal rainfall. In recent years, tropical cyclone (TC) activity over the Main Development Region (MDR) of the tropical North Atlantic has a negative impact on regional seasonal precipitation over northern South America. High TC activity over MDR corresponds to below-normal precipitation because it reduces the EW activity reaching northern South America through the recurving of TC tracks. Recurving TC tracks redirect moisture away from the tropical belt and into the mid-latitudes. However, this relationship only holds under neutral ENSO conditions and the positive phase of the Atlantic Multidecadal Oscillation. A 10-member regional model multi-physics ensemble simulation for the period 1990–2000 was analyzed to show the relationships are robust to different representations of physical processes. This new understanding of seasonal rainfall over the tropical Americas may support improved regional seasonal and climate outlooks. © 2019, The Author(s).
英文关键词	Easterly waves; Observations; Regional model; Seasonal precipitation; Tropical cyclone tracks
语种	英语
scopus关键词	climate modeling; easterly wave; El Nino-Southern Oscillation; frequency analysis; mesoscale meteorology; numerical model; rainfall; regional climate; tracking; tropical cyclone; South America
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145769
作者单位	Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior, Ciudad Universitaria, Mexico City, 04510, Mexico; National Center for Atmospheric Research, Boulder, CO, United States; Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
推荐引用方式 GB/T 7714	Dominguez C.,Done J.M.,Bruyère C.L.. Easterly wave contributions to seasonal rainfall over the tropical Americas in observations and a regional climate model[J],2020,54(2020-01-02).
APA	Dominguez C.,Done J.M.,&Bruyère C.L..(2020).Easterly wave contributions to seasonal rainfall over the tropical Americas in observations and a regional climate model.Climate Dynamics,54(2020-01-02).
MLA	Dominguez C.,et al."Easterly wave contributions to seasonal rainfall over the tropical Americas in observations and a regional climate model".Climate Dynamics 54.2020-01-02(2020).