中国华北地区冬季降水异常特征及其与大气环流和海温的关系  

Characteristics of North China winter precipitation anomaly and its relationship with atmospheric circulation and SST

作　　者：孙照渤[1,2] 刘华 倪东鸿[1,2] 

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5期577-586,共10页Transactions of Atmospheric Sciences

基　　金：国家自然科学基金资助项目(41575102);国家重点基础研究发展计划(973计划)项目(2013CB430202)

摘　　要：利用1951—2012年中国冬季160站降水资料、NCEP/NCAR再分析资料及NOAA海温资料,分析了中国华北地区冬季降水的异常变化特征及其与大气环流和海温的关系。结果表明:华北地区冬季降水主要呈现为全区一致变化的特征,且年际变率较大,具有2~4 a的年际变化周期。降水异常偏多(少)年,西伯利亚高压偏弱(强),阿留申低压偏弱(强),850 h Pa上华北地区盛行的西北风较弱(强),控制该地区的东亚冬季风偏弱(强),该地区有偏南(北)风距平,500 h Pa上东亚槽脊系统偏弱(强)。影响华北地区冬季降水的异常水汽主要来源于南海及其以东的西太平洋。前期夏季日本以东的西风漂流区、同期冬季近海的黄渤海区域的海温均与中国华北地区冬季降水存在显著的正相关关系。It is of great importance to study winter precipitation because it can directly affect agricultural production and public travel,and even threaten human safety. For lack of researches on winter precipitation,especially in North China,this paper mainly focuses the distribution and evolution of winter precipitation in North China. Based on the winter precipitation data at 160 stations in China,the NCEP/NCAR reanalysis data and the NOAA ERSST data during 1951/1952—2012/2013,the characteristics of winter precipitation anomaly in North China and its relationship to atmospheric circulation and sea surface temperature( SST) are studied. Common statistical methods including EOF reanalysis,synthesis analysis and correlation analysis are effectively used. The overall characteristics of winter precipitation indicates that although the total amount of precipitation is small,the precipitation variability is large in North China. EOF analysis results showthat there are characteristics of uniform change of the whole area for winter precipitation in North China,and the interannual variability is large,with 2—4 years period. Based on the winter precipitation index defined by the data of 19 representative stations in North China,the more and less winter precipitation years are obtained. During the more( less) precipitation years,Siberian high is weaker( stronger),Aleutian lowis weaker( stronger),and the northwest cold air is also weaker( stronger). At 850 h Pa,the prevalent northwest wind in North China is weaker( stronger),East Asian winter monsoon dominating North China is weaker( stronger) simultaneously,and the southerly( northerly) wind anomaly also exists in North China. At 500 h Pa,East Asian trough and Ural ridge are both weaker( stronger),the blocking system in mid-latitudes is weaker( stronger),and the flat westerly current( strong northwest wind) anterior the ridge takes control. Furthermore,two dominating water vapor transport channels that affect North China winter precipitation are found:one from South China Sea,

关 键 词：华北 冬季降水 大气环流 水汽输送 海面温度 

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