东亚副热带急流经向位置对中国西北东部盛夏降水的影响  

Effect of Meridional Position of East Asian Subtropical Jet on Midsummer Precipitation in Eastern Part of Northwest China

作　　者：姬凯 王士新 左洪超[1] 王一璞 丁瑞强[3] JI Kai;WANG Shi-xin;ZUO Hong-chao;WANG Yi-pu;DING Rui-qiang(College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,Gansu,China;Institute of Hydrology and Water Resources,Nanjing University of Information Science and Technology,Nanjing 210044,Jiangsu,China;Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China)

机构地区：[1]兰州大学大气科学学院,甘肃兰州730000 [2]南京信息工程大学水文与水资源工程学院,江苏南京210044 [3]中国科学院大气物理研究所,北京100029

出　　处：《干旱区研究》2020年第1期10-17,共8页Arid Zone Research

基　　金：国家自然基金项目(41875009,41805052)共同资助

摘　　要：选取国家气象信息中心整编的中国179个气象站逐日降水资料,以及NCEP/NCAR逐月再分析资料,在分析1979-2017年西北地区东部的盛夏(7、8月)降水变化特征的基础上,利用东亚副热带西风急流经向位置指数,重点讨论东亚副热带西风急流经向位置变化与西北地区东部盛夏降水的关系,以期进一步提高对西北地区旱涝灾害的预测水平。结果表明:在东亚副热带西风急流中心经向位置异常偏北年,西北地区东部偏北区域盛夏降水较常年多,而西北地区东部偏南区域盛夏降水较常年少,反之亦然。表现出东亚副热带西风急流经向位置变化对西北地区东部盛夏降水影响的南北带状反向分布特征。Many studies have shown that the East Asian subtropical westerly jet is closely related to the summer precipitation in most parts of China,but there are relatively few related studies in Northwest China. In this papers,the daily precipitation data from 179 meteorological stations in China,compiled by the National Meteorological Information Center,and the monthly analysis of NCEP/NCAR data were used to analyze the change of precipitation in midsummer (from July to August) in the eastern part of Northwest China from 1979 to 2017. On the basis of the East Asian subtropical westerly jet meridional position index,the relationship between the change of eastward subtropical westerly jet meridional position and the midsummer precipitation in the eastern part of Northwest China was discussed. The purpose of the study was to further improve the level of predicting drought and flood disasters in Northwest China. The results showed that the midsummer precipitation in the northeastern part of Northwest China was higher in the abnormal years when the center of East Asian subtropical westerly jet was northward,and vice versa. These showed that the change of subtropical westerly jet meridional position affected the change of midsummer precipitation in the eastern part of Northwest China.

关 键 词：盛夏降水 气候变化 东亚副热带急流经向位置 西北地区东部 

分 类 号：P461[天文地球—大气科学及气象学]