Variation in Principal Modes of Midsummer Precipitation over Northeast China and Its Associated Atmospheric Circulation  

作　　者：Tingting HAN Shengping HE Huijun WANG Xin HAO 

机构地区：[1]Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster,Ministry of Education,Nanjing University for Information Science and Technology [2]Nansen-Zhu International Research Centre,Institute of Atmospheric Physics,Chinese Academy of Sciences [3]Geophysical Institute,University of Bergen and Bjerknes Centre for Climate Research [4]Climate Change Research Center,Chinese Academy of Sciences

出　　处：《Advances in Atmospheric Sciences》2019年第1期55-64,共10页大气科学进展（英文版）

基　　金：supported by the National Key Research and Development Program of China (Grant No.2016YFA0600703);the National Natural Science Foundation of China (Grant No.41805046);the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No.18KJB170013);the Startup Foundation for Introducing Talent of NUIST (Grant No.2243141701085);the funding of the Jiangsu Innovation and Entrepreneurship Team

摘　　要：This study documents the first two principal modes of interannual variability of midsummer precipitation over Northeast China （NEC） and their associated atmospheric circulation anomalies. It is shown that the first principal mode exhibits the largest amount of variability in precipitation over the south of NEC （referred to as the south mode）, whereas the second principal mode behaves with the greatest precipitation anomaly over the north of NEC （referred to as the north mode）. Further findings reveal that, through modulating moisture transportation and upper- and lower-troposphere divergence circulation as well as vertical movement over NEC, the anomalous northwestern Pacific anticyclone and the anticyclone centered over northern NEC exert the dominant influence on the south and north modes, respectively. Additionally, it is quantitatively estimated that water vapor across the southern boundary of NEC dominates the moisture budget for the south mode, while the north mode has a close connection with moisture through NEC＇s northern and western boundal＇ies. Furthermore, the north （south） mode is strongly related to the intensity （meridional shift） of the East Asian westerly jet.This study documents the first two principal modes of interannual variability of midsummer precipitation over Northeast China(NEC) and their associated atmospheric circulation anomalies. It is shown that the first principal mode exhibits the largest amount of variability in precipitation over the south of NEC(referred to as the south mode), whereas the second principal mode behaves with the greatest precipitation anomaly over the north of NEC(referred to as the north mode). Further findings reveal that, through modulating moisture transportation and upper-and lower-troposphere divergence circulation as well as vertical movement over NEC, the anomalous northwestern Pacific anticyclone and the anticyclone centered over northern NEC exert the dominant influence on the south and north modes, respectively. Additionally, it is quantitatively estimated that water vapor across the southern boundary of NEC dominates the moisture budget for the south mode, while the north mode has a close connection with moisture through NEC's northern and western boundaries. Furthermore, the north(south) mode is strongly related to the intensity(meridional shift) of the East Asian westerly jet.

关 键 词：Northeast China PRECIPITATION northwestern Pacific anticyclone Northeast China anticyclone 

分 类 号：P426.614[天文地球—大气科学及气象学] P434