气候变化领域集成服务门户(CCPortal): East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal-to-Interannual Timescales

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DOI	10.1029/2021JD034607
	East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal-to-Interannual Timescales
	Wang X.; Guan Z.; Jin D.; Zhu J.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:18
英文摘要	In summer 2020, extreme rainfall occurred over the middle and lower reaches of the Yangtze River Basin (YRB). The accumulated precipitation amount of this rainfall event broke the record since 1961. On the interannual timescale, seasonal mean rainfall anomalies in the YRB during summer 2020 are related to the tropical North Indian Ocean (NIO) sea surface temperature (SST) warming and a La Niña event in the equatorial eastern Pacific. Both the NIO SST warming and La Niña help to generate the anomalous tropospheric low-level Northwest Pacific anticyclone (NWP-AAC) via the Matsuno-Gill type response. On the subseasonal timescale, rainfall anomalies in the YRB exhibit two significant periods during summer 2020, intraseasonal (40–60 days) and quasi-biweekly (∼10 days). The former intraseasonal component is the focus of this study. The intraseasonal NWP-AAC, which is a part of tropical intraseasonal oscillation, plays a dominant role in connecting the East Asian summer monsoon (EASM) rainfall with tropical convection. Using the pattern regression, a real-time index (RTI) is proposed to represent the intraseasonal-to-interannual variability of the NWP-AAC. The RTI captures the quasi-biennial tendency of NWP-AAC as well as its intraseasonal variability. These suggest that the NWP-AAC is a common mode across timescales. Also, the RTI well depicts the EASM rainfall variability in 2020. Our results provide an alternative view of cross-scale EASM variability, with an emphasis on the conduit effect of NWP-AAC from intraseasonal to interannual timescale. Hence, the RTI could be utilized for subseasonal to seasonal climate monitoring in the Asian summer monsoon region. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	East Asian summer monsoon; ISO; La Niña; Northwest Pacific anticyclone
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/237013
作者单位	Key Laboratory of Ministry of Education for Meteorological Disaster/International Joint Laboratory on Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing, China; Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences, Fudan University, Shanghai, China
推荐引用方式 GB/T 7714	Wang X.,Guan Z.,Jin D.,et al. East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal-to-Interannual Timescales[J],2021,126(18).
APA	Wang X.,Guan Z.,Jin D.,&Zhu J..(2021).East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal-to-Interannual Timescales.Journal of Geophysical Research: Atmospheres,126(18).
MLA	Wang X.,et al."East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal-to-Interannual Timescales".Journal of Geophysical Research: Atmospheres 126.18(2021).