气候变化领域集成服务门户(CCPortal): New insights into the rainfall variability in the tropical Andes on seasonal and interannual time scales

CCPortal

DOI	10.1007/s00382-018-4590-8
	New insights into the rainfall variability in the tropical Andes on seasonal and interannual time scales
	Segura H.; Junquas C.; Espinoza J.C.; Vuille M.; Jauregui Y.R.; Rabatel A.; Condom T.; Lebel T.
发表日期	2019
ISSN	0930-7575
起始页码	405
结束页码	426
卷号	53 期号:2020-01-02
英文摘要	In this study, we analyze the atmospheric mechanisms associated with the main rainfall patterns in the tropical Andes (20 ∘S –1 ∘N) on seasonal and interannual time scales. Using a homogeneous and high spatial resolution precipitation data set (0. 05 ∘× 0. 05 ∘) at monthly time step (CHIRPS; 1981–2016), in-situ precipitation from 206 rain-gauge stations, power spectrum and EOF analysis, we identify three Andean regions characterized by specific seasonal and interannual rainfall modes: the equatorial Andes (EA, 5 ∘S –1 ∘N), the transition zone (TZ, 8 ∘S –5 ∘S) and the southern tropical Andes (STA, 20 ∘S –8 ∘S). On seasonal time scales, the main mode of precipitation in the EA and STA are characterized by a unimodal regime, while the TZ is represented by a bimodal regime. The EA and the TZ share the same wet season in the February–April period, which is associated with a weakened Walker Cell, the southerly position of the Intertropical Convergence Zone (ITCZ) and a strong westward humidity transport from the equatorial Amazon. This latter mechanism and a reduced elevation of the Andes are associated with the October–November wet season in the TZ. The presence of the Bolivian High and the northward extension of the Low Level Jet are associated with the precipitation over Andean regions between 20∘S and 8∘S in the December–March period. On interannual time scales, extreme monthly wet events (EMWE) in the STA (TZ) are related to convection over the western (equatorial) Amazon during the December–March (February–April) period, showing an atmospheric relationship between the Amazon and the Andes. Extreme monthly dry events (EMDE) in the TZ and in the EA during the February–April period are related to a strengthened Walker Cell, especially in the eastern Pacific. In addition, EMWE (EMDE) in the EA are associated with an anomalous southward (northward) displaced eastern Pacific ITCZ. Moreover, we find a relationship between precipitation at higher elevations in the Andes north of 10 ∘S and easterly winds at 200 hPa during February–April EMWE. Finally, extreme monthly events in the EA (STA) are related to sea surface temperature anomalies in the western (central) equatorial Pacific. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Atmospheric mechanisms; EOF analysis; Precipitation; Seasonal and interannual variability; Tropical Andes
语种	英语
scopus关键词	annual variation; climate modeling; empirical orthogonal function analysis; extreme event; intertropical convergence zone; precipitation assessment; rainfall; sea surface temperature; seasonal variation; spatial resolution; trend analysis; tropical region; Andes; Pacific Ocean; Pacific Ocean (East); Pacific Ocean (Equatorial)
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/146193
作者单位	Univ. Grenoble Alpes, IRD, CNRS, G-INP, IGE (UMR 5001), Grenoble, 38000, France; Instituto Geofísico del Perú (IGP), Lima, Peru; Department of Atmospheric and Environmental Sciences, State University of New York at Albany, Albany, NY, United States; Department of Atmospheric Sciences, University of Washington, Seattle, United States
推荐引用方式 GB/T 7714	Segura H.,Junquas C.,Espinoza J.C.,et al. New insights into the rainfall variability in the tropical Andes on seasonal and interannual time scales[J],2019,53(2020-01-02).
APA	Segura H..,Junquas C..,Espinoza J.C..,Vuille M..,Jauregui Y.R..,...&Lebel T..(2019).New insights into the rainfall variability in the tropical Andes on seasonal and interannual time scales.Climate Dynamics,53(2020-01-02).
MLA	Segura H.,et al."New insights into the rainfall variability in the tropical Andes on seasonal and interannual time scales".Climate Dynamics 53.2020-01-02(2019).