大连盛夏旱涝典型年环流对比分析  

Comparison analysis of circulation anomalies in midsummer between drought and flood years in Dalian

作　　者：王秀萍 陈希壮[2] 程航 金巍[3] WANG Xiu-ping;CHEN Xi-zhuang;CHENG Hang;JIN Wei(Dalian Meteorological Observatory,Dalian 116001,China;Dalian Meteorological Service,Dalian 116001,China;Anshan Meteorological Service,Anshan 114004,China)

机构地区：[1]大连市气象台,辽宁大连116001 [2]大连市气象局,辽宁大连116001 [3]鞍山市气象局,辽宁鞍山114004

出　　处：《气象与环境学报》2018年第6期84-90,共7页Journal of Meteorology and Environment

基　　金：空间天气学国家重点实验室开放课题"地磁活动因子对气候要素的影响研究"(Y72612A28S);2016年辽宁省气象部门认定项目成果"省市级短时临近预报业务系统(SWAN)的本地化应用";渤海区域科技协同创新基金项目(QYXM21711)共同资助

摘　　要：利用1964—2016年大连地区6个气象观测站逐月降水资料、NCEP/NCAR再分析月平均资料和国家气候中心提供的西太平洋副热带高压环流特征量资料,采用相关分析和合成分析的方法,分析了大连地区盛夏(7—8月)旱涝的大气环流异常特征,并从大气环流异常的角度揭示了大连地区盛夏旱涝的成因。结果表明:大连地区盛夏涝(旱)年,200 h Pa东北地区西风急流强(弱)、长江流域西风急流弱(强),500 h Pa西太平洋副热带高压脊线偏北(南),东亚大槽偏西(东),850 h Pa南风异常偏强(弱),大连地区所在经度上垂直速度的经圈环流在大连上空出现异常上升(下沉)运动,从而导致大连地区盛夏降水异常偏多(少)。Based on the observed monthly precipitation data at 6 stations in Dalian from 1964 to 2016,the NCEP/NCAR monthly mean reanalysis data during 1948-2016 and the circulation feature data of the western Pacific subtropical high(WPSH)given by the National Climate Center,the characteristics of the atmospheric circulation anomalies of the extremely drought/flood occurrences from July to August were studied using the methods of composite analysis and correlation analysis.Meanwhile,the causes of midsummer drought and waterlogging were revealed by considering atmospheric circulation anomalies.The results show that in midsummer waterlogging(drought)years in Dalian area,the northeast China westerly jet at 200 hPa is stronger(weaker)and the Yangtze River Valley westerly jet is weaker(stronger).At the same time,the location of the Western Pacific Subtropical high ridge line is more-northward(more-southward)and that of the East Asia trough is more-westward(more-eastward)at 500 hPa as well as the south wind anomalies at 850hPa is stronger(weaker).In addition,the anomalous ascending(descending)motions occur in the meridional circulation of vertical speed along the longitude of Dalian,which results in midsummer precipitation anomalously increasing(decreasing)over Dalian area.

关 键 词：旱涝 环流异常 西风急流 

分 类 号：P461[天文地球—大气科学及气象学]