Joint Effect of East Asia-Pacific and Eurasian Teleconnections on the Summer Precipitation in North Asia  

作　　者：Po HU Guolin FENG Muhammad Mubashar DOGAR Jianbo CHENG Zhiqiang GONG 

机构地区：[1]Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research,Institute of Heavy Rain,China Meteorological Administration,Wuhan 430205,China [2]National Climate Center,China Meteorological Administration,Beijing 100081,China [3]Global Change Impact Studies Centre(GCISC),Ministry of Climate Change,Islamabad 44000,Pakistan [4]College of Physical Science and Technology,Yangzhou University,Yangzhou 225002,China [5]College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China

出　　处：《Journal of Meteorological Research》2020年第3期559-574,共16页气象学报（英文版）

基　　金：Supported by the National Key Research and Development Program of China(2018YFA0606301 and 2018YFC1507702);National Natural Science Foundation of China(41875100,41575082,and 41530531).

摘　　要：The East Asia-Pacific(EAP)and Eurasian(EU)teleconnections are independent of each other on the seasonal timescale(with a correlation coefficient of only 0.03).But they may occur concurrently with consistent or opposite phases.This paper investigates their synergistic effect on the summer precipitation in North Asia.Based on the signs/phases of EAP and EU indices,the EAP and EU teleconnection anomalies occur in four cases:(Ⅰ)positive EAP+positive EU,(Ⅱ)negative EAP+negative EU,(Ⅲ)positive EAP+negative EU,and(Ⅳ)negative EAP+positive EU.Further analyses show that these four configurations of EAP and EU anomalies are coherently related to different atmospheric circulations over the midlatitude Eurasian continent,leading to different summer precipitation modes in North Asia.CategoryⅠ(Ⅱ)corresponds to a zonal tripole structure of the geopotential height at 500 hPa over eastern Europe and the Sea of Japan,leading to less(more)than normal precipitation in eastern Europe,Japan,and the surrounding areas,and more(less)precipitation from central China to Lake Baikal and eastern Russia.CategoryⅢ(Ⅳ)corresponds to a meridional dipole structure of the geopotential height at 500 hPa over North Asia,leading to more(less)precipitation in the northern North Asia and less(more)precipitation in most of the southern North Asia.Independent analysis reveals that the EAP teleconnection itself is positively correlated with the precipitation in the region between the eastern part of Lake Baikal and Okhotsk Sea,and negatively correlated with the precipitation in the region between Northeast China and Japan.Coincidently,the EU pattern and precipitation have negative correlations in Ural Mountain and Okhotsk Sea areas and positive correlations in the Lake Baikal area.The respective relations of EAP and EU with the summer precipitation in North Asia suggest that the EAP northern lobe overlapped with the EU central and eastern lobes could extend the geopotential anomalies over Lake Baikal to Russian Far East,creating an EAP-EU sy

关 键 词：East Asia–Pacific(EAP)teleconnection Eurasian(EU)teleconnection synergistic effect precipitation 

分 类 号：P426.6[天文地球—大气科学及气象学]