“0801南方雪灾”水汽通量与降水关系的SVD分析  

SVD ANALYSIS BETWEEN THE MOISTURE FLUX AND PRECIPITATION IN "0801 SNOW STORM OVER SOUTHERN CHINA"

作　　者：杨玮[1,2] 何金海[1,2] 王佳[1,2] 王盘兴[1,2] 

机构地区：[1]气象灾害省部共建教育部重点实验室,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：《热带气象学报》2011年第5期697-702,共6页Journal of Tropical Meteorology

基　　金：科技部项目"极端天气气候事件的检测和可预测性关键技术研究"(2007BAC29B00);科技部国家支撑计划项目"南方冰雪灾害的天气成因研究"(2008BAC48B02)共同资助;江苏省普通高校研究生科研创新计划(CXZZ11_0608)

摘　　要：利用2008年1月10日—2月2日的NCEP/NCAR逐日风场、比湿、地面气压资料以及中国地面国际交换站194站的逐日降水资料,分析我国"0801南方雪灾"期间水汽通量场的特征,结果表明我国南方是整层水汽通量及其散度的高值区。用奇异值分解(SVD)方法,分析了水汽输送通量异常场和降水异常场之间的关系,揭示出两对统计显著且天气意义清晰的耦合模态。其中,第一对模态的方差贡献率为81.50%,相应左、右奇异向量时间系数的相关系数为0.80,主要描述源自孟加拉湾及南海的西南风水汽输送异常增强并在我国川、滇、黔交界处及粤、闽、赣一带辐合时,长江以南大部分地区多雨;第二对模态方差贡献率为8.80%,相关系数为0.64,主要描述当中国大陆东部有源自西太平洋的水汽输送异常增强并在广西-浙江沿线区域辐合时,长江中下游流域多雨,但华南三省(广西、广东和福建)少雨。Using the daily wind field,specific humidity,surface air pressure data of NCEP/NCAR and daily precipitation data of 194 stations in China for the period of January 10 to February 2,2008,characteristics of moisture flux field in ＂0801 snow storm over southern china＂ are analyzed.It is shown that there exists a high value area of the vertically integrated moisture transport and its divergence in southern China.By means of singular value decomposition（SVD） method,the relationship between the anomaly field of moisture transport flux and rainfall anomalies is investigated.And two pairs of coupled modes with statistical significance and distinct synoptic meteorological significance are revealed.Among them,the first modes with the variance contribution rate of 81.50% and the correlation coefficient for its time coefficient of 0.80 describe that when the southwest winds moisture transport anomalies from the Bay of Bengal and South China Sea strengthen,but also converge in the junction of Sichuan,Yunnan,Guizhou and areas of Guangdong,Fujian,Jiangxi in China,it is rainy in most parts of the south of the Yangtze River.The second modes with the variance contribution rate of 8.80% and the correlation coefficient for its time coefficient of 0.64 indicate that when the moisture transport anomalies from the western Pacific Ocean enhance in eastern Chinese mainland and converge along the Guangxi-Zhejiang region,it is rainy in the middle and lower Yangtze River Basin,but rainless in Guangxi,Guangdong and Fujian.

关 键 词：“0801南方雪灾” 水汽通量 降水 奇异值分解 

分 类 号：P429[天文地球—大气科学及气象学]