奇异值分解和奇异交叉谱分析方法在华北夏季降水诊断中的应用  

APPLICABILITY OF SINGULAR VALUE DECOMPOSITION AND SINGULAR CROSS-SPECTRUM TO DIAGNOSE OF RAINFALL IN NORTH CHINA

作　　者：尤凤春 丁裕国[2] 周煜[3] 史印山 

机构地区：[1]河北省气象台,石家庄050021 [2]南京气象学院,南京210044 [3]中国气象局,北京100081

出　　处：《应用气象学报》2003年第2期176-187,共12页Journal of Applied Meteorological Science

摘　　要：利用 1 965～ 2 0 0 0年华北 5省市及相邻省 73个地面观测站逐月平均降水场及北半球50 0hPa高度场、北太平洋海温场资料 ,采用奇异值分解 (SVD)、奇异交叉谱 (SCSA)分析方法 ,将华北夏季降水场分别与 1月北半球 50 0hPa高度场、冬季北太平洋海温场进行了诊断分析 ,得出奇异向量分布型及相互作用的耦合周期信号。在对前 4对奇异向量的分析中发现 ,华北夏季降水全区域为正距平时与 1月北半球 50 0hPa高度场PNA遥相关型关系非常密切。ENSO对华北夏季降水的影响确实存在 ,但华北夏季降水全区域为正距平时与冬季北太平洋ENSO关系并不明显。同时还找出了华北降水与北半球 50 0hPa高度、北太平洋海温场相互作用的关键区。在华北各型降水与高度场、海温场关键区相互作用的耦合周期中 ,前者以准 2～ 7年振荡为主 ;后者则周期较长 ,最短周期仍为准 2年振荡 ,最长周期为准1 0～ 1 1年振荡。以上结论为进一步研究华北夏季降水短期气候预测方法 ,提供了参考依据。Based on the monthly mean precipitation data of 1965-2000 from 73 meteorological stations in North China, the diagnostic analyses of the January Northern Hemisphere 500 hPa height field and the winter Northern Pacific Ocean sea surface temperature (SST) field associated with summer precipitation over North China are made by singular value decomposition (SVD) and singular cross spectrum analysis (SCSA) methods. The results show that there is a close PNA teleconnection pattern between 500 hPa height field and summer North China precipitation when the summer precipitation anomaly is positive. ENSO has a definite impact on summer North China precipitation, but there is not notable relation between summer precipitation and winter ENSO in the Northern Pacific Ocean when the precipitation anomaly is positive. The key regions of interaction between North China precipitation and Northern Hemisphere 500 hPa height field and that between precipitation and SST are further found. For the interaction between North China precipitation and 500 hPa height field, the dominated coupled oscillation periods are quasi two years and quasi seven years. For the interaction between North China precipitation and SST, the periods are longer——the shortest is the quasi 2 year oscillation and the longest is 10 or 11 year oscillation.

关 键 词：奇异值分解 奇异交叉谱分析方法 夏季 降水 华北地区 海温场 遥相关 短期气候预测 

分 类 号：P458.1[天文地球—大气科学及气象学]