华南春季降水的年代际变化及其与大气环流和海温的关系  

Interdecadal variation of spring precipitation in South China and its relationships with atmospheric circulation and SST

作　　者：孙照渤[1,2] 徐青竹 倪东鸿[1,2] SUN Zhaobo;XU Qingzhu;NI Donghong(Key Laboratory o f Meteorological Disaster, Ministry of Education ( KLME) / Joint International Research Laboratory of Climate and Environment Change {ILCEC) /Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD) ,Nanjing University of Information Scien;School of Atmospheric Sciences, Nanjing University of Information Science & Technology, Nanjing 210044, China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心,江苏南京210044 [2]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《大气科学学报》2017年第4期433-442,共10页Transactions of Atmospheric Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2013CB430202);国家自然科学基金资助项目(41575085;41430528)

摘　　要：利用1960—2010年中国降水资料、NCEP/NCAR再分析资料、NOAA提供的海表温度资料以及太平洋年代际振荡(Pacific Decadal Oscillation,PDO)指数,分析了华南春季降水的年代际变化特征及其与大气环流和海温的关系。结果表明:华南春季降水经历了偏少(1960—1971年)—偏多(1972—1992年)—次偏少(1993—2010年)三个阶段。第一阶段少雨期,500 hPa上西风气流较平直,不利于北方冷空气南下,华南地区的暖气团也不活跃,对应的水汽通量散度为异常辐散。第二阶段多雨期,500 hPa高度上,高原北部脊偏强,利于冷空气南下,与华南地区活跃的暖湿气团汇合,对应的水汽场上为水汽异常辐合。第三阶段少雨期,500 hPa西风气流上的槽脊系统偏强,利于北方强冷空气南下,孟加拉湾地区的南支槽填塞,南方暖湿空气向华南的输送减弱。华南春季降水与PDO指数存在正相关关系,从不同季节来看,在年代际时间尺度上,前期秋季的PDO指数与华南春季降水的正相关显著,PDO处于负位相时,华南春季降水偏少,反之亦然;从华南春季降水年代际变化的不同阶段来看,PDO指数与华南春季降水的正相关在1960—1971年少雨期较显著。South China is one of the most frequent drought and flood areas in China.The main characteristics of precipitationin South China are long rainy season and large rainfall.Studying the distribution characteristics and variationrules of spring precipitation in South China can be used as a basis for the allocation and utilization of precipitationresources in spring and the early warning of drought and flood in South China.Most studies have mainly focusedon the characteristics of spring precipitation and its influencing factors in South China at present,while there arefew studies about the interdecadal variation of spring precipitation in South China.Interdecadal climate change isthe background of monthly,seasonal and interannual climate changes and forecasts,and also affects climatechange over a longer period of time.It is one of the key issues of climate change.So this paper intends to study theinterdecadal variation of spring precipitation in South China,and the corresponding characteristics of atmosphericcirculation and sea surface temperature(SST)anomaly.To investigate the subject of spring precipitation of48stations in South China,its interdecadal variation characteristicsand its relationships with atmospheric circulation and SST,the daily precipitation data in China,NCEP/NCAR reanalysis data,and Pacific Decadal Oscillation(PDO)index and SST data provided from NOAAduring1960-2010are used.This paper uses the common meteorological statistical methods and diagnostic analysismethods.It is found that spring precipitation in South China has experienced three stages:during1960-1971,the precipitationis less than normal;during1972-1992,it is more than normal;during1993-2010,it is still less thannormal,but the reduction degree is weaker than that in the first stage.There are great differences in the circulationbackground fields among the different stages of interdecadal variation of spring precipitation in South China.In thefirst stage,the westerly is flat at500hPa,which is not helpful for the north cold air southward.The

关 键 词：华南 春季降水 年代际变化 大气环流 海温 

分 类 号：P426.6[天文地球—大气科学及气象学] P434P731.11