长江中下游夏季雨带分型及其年代际变化Ⅰ:统计特征  

Summer Rain Band Pattern in Mid-Lower Reaches of Yangtze River and Its Interdecadal Variability Ⅰ:Statistical Characters

作　　者：潘敖大[1] 孙照渤[1] 

机构地区：[1]南京信息工程大学江苏省气象灾害重点实验室

出　　处：《南京气象学院学报》2007年第4期487-494,共8页Journal of Nanjing Institute of Meteorology

基　　金：江苏省高校自然科学重大基础研究项目(05KJA17002);国家重点基础研究发展计划项目(2004CB418303);江苏省气象灾害重点实验室资助项目(KLME050304)

摘　　要：利用中国气象局提供的1951—1998年全国160站月平均降水资料及NCEP/NCAR月平均再分析资料,采用REOF方法分析,结果表明:长江中下游地区夏季降水可以显著分为南北两支雨带,一支位于长江中下游以南,江西、湖南和浙江一线;另一支位于重庆、陕西东南部、湖北、河南南部和安徽一线,都呈现出东西向的带状分布。分析还表明:这两支雨带具有明显的年际和年代际变化特征;在年代际尺度上,南支雨带表现为14 a的主周期,而北支雨带表现为8 a的主周期,且两支雨带降水的多寡时段有明显的不同;东亚夏季风和西太平洋副热带高压的强弱对两支雨带降水的多少和分布形态有重要影响。　It is important to study the reasons and characters for summer drought and flood and its rainfall anomaly distribution in the Changjiang-Huaihe River Basin.By using the NCEP/NCAR reanalysis data and the 1951—1998 summer rainfall data of 160 stations from CMA,the REOF analysis of summer（JJA） precipitation in eastern China was performed,and results show that the distribution of summer rainfall in the middle-lower reaches of Yangtze River can be described by two zonal rain bands：the southern branch band lies to south of the lower reach of Yangtze River,along the Hunan-Jiangxi-Zhejiang area;another locates along the southeast of Chongqing and Shaanxi-Hubei-the south of Henna-Anhui area.Interannual and interdecadal features for both branch bands are obvious with the 14-yr period in the southern branch band and the 8-yr period in the northern branch band.And moreover the both branch bands have different time periods of excessive/deficit rainfall,which is close related with the general circulation,especially the intensities of summer monsoon and subtropical high have significant impacts on both the location and size of their precipitation.

关 键 词：长江中下游 年代际变化 降水 夏季风指数 副高指数 

分 类 号：P463.1[天文地球—大气科学及气象学]