气候变化领域集成服务门户(CCPortal): On the dynamic mechanisms of intense rainfall events in the central Andes of Peru, Mantaro valley

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DOI	10.1016/j.atmosres.2020.105188
	On the dynamic mechanisms of intense rainfall events in the central Andes of Peru, Mantaro valley
	Flores-Rojas J.L.; Moya-Álvarez A.S.; Valdivia-Prado J.M.; Piñas-Laura M.; Kumar S.; Karam H.A.; Villalobos-Puma E.; Martínez-Castro D.; Silva Y.
发表日期	2021
ISSN	0169-8095
卷号	248
英文摘要	The present study was aimed at analysing the main atmospheric dynamic mechanisms associated with the occurrence of intense rainfall events above the Huancayo observatory (12.05°S, 75.32°W, 3313 m asl) in the central Andes of Perú (Mantaro valley) from January 2018 to April 2019. To identify the rainfall events, we used a set of instruments from the laboratory of physics, microphysics and radiation (LAMAR) composed by in-situ pluviometric observations, satellite remote sensing data (GPM), Cloud Radar (MIRA-35c), Boundary Layer Tropospheric Radar (BLTR) and downscaling model simulations with WRF (resolutions: 18 km, 6 km and 2 km) and ARPS (0.5 km) models to analyse the dynamics of the atmosphere for the synoptic, meso and local processes that control the occurrence of these rainfall events. The results showed that all intense rainfall events are associated with the presence of thermal meso-scale circulations that transport moisture fluxes through passes with gentle slopes along both sides of the Andes. The easterly moisture fluxes come in from the South America Low Level Jet (SALLJ) and the westerly moisture fluxes from the Pacific Ocean. The arrival of these moisture flows to regions within the Mantaro valley depends on their coupling with the circulations at medium and high levels of the atmosphere. At the synoptic scale, the results show that the rainfall events can be separated into two groups: the first one associated with westerly circulations (WC) at the mid and upper levels of the atmosphere, generated by the weakening and eastern displacement of the anticyclonic Bolivian high-North east low (BH-NE) system, and the second associated with easterly circulations (EC) at the mid and upper levels of the atmosphere, generated by the intensification of the BH-NE system. The observed and simulated results showed that multicell convective systems of WC events are more extensive and deeper than EC events. This situation can be explained as the convergence of moisture fluxes from opposite directions occurred within the Mantaro basin for WC events. In contrast, for EC events, the convergence develops at the east Andes mountain range, following which the multicell storm system propagates westward, driven by easterly circulations. The EC events occur mostly in the summer months, while the WC events occur mostly in the autumn and spring months. Moreover, apparently the inertia gravity waves (IGWs) formed in the Amazon basin transport moisture and energy to the central Andes plateau and intensify the convection processes. © 2020
英文关键词	Dynamic analysis; Inertia gravity waves; Mantaro basin; Model simulations; Rainfall events
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/236919
作者单位	Geophysical Institute of Perú, Calle Badajoz 169 Urb. Mayorazgo IV Etapa. Ate, Lima, 15012, Peru; Universidade Federal de Rio de Janeiro, Rio de Janeiro - UFRJ / IGEO / CCMN, Rua Athos da Silveira Ramos, 274, Cidade Universitária - Ilha do Fundão Rio de Janeiro - RJ, Brazil
推荐引用方式 GB/T 7714	Flores-Rojas J.L.,Moya-Álvarez A.S.,Valdivia-Prado J.M.,et al. On the dynamic mechanisms of intense rainfall events in the central Andes of Peru, Mantaro valley[J],2021,248.
APA	Flores-Rojas J.L..,Moya-Álvarez A.S..,Valdivia-Prado J.M..,Piñas-Laura M..,Kumar S..,...&Silva Y..(2021).On the dynamic mechanisms of intense rainfall events in the central Andes of Peru, Mantaro valley.Atmospheric Research,248.
MLA	Flores-Rojas J.L.,et al."On the dynamic mechanisms of intense rainfall events in the central Andes of Peru, Mantaro valley".Atmospheric Research 248(2021).