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利用青藏高原70个常规气象站地面观测资料结合卫星遥感观测的归一化差值植被指数(NDVI)数据集计算的1982-2012年逐月地表感热通量资料和1951-2012年国家气候中心160个站的夏季降水资料,以及NCEP Ⅰ再分析数据集,通过EOF、SVD等数理统计分析方法,分析了高原春季地表感热的时空演变特征及其对中国东部夏季雨带的影响及其成因.结果表明:(1)20世纪90年代中国东部处于多雨期,江南地区降水尤为偏多,Ⅲ类雨型偏多;进入21世纪,夏季雨带向北推进,Ⅱ类雨型偏多.(2)高原春季地表感热空间分布呈现“西强东弱”的特征,5月最强且年际变化最大;在空间演变上,主要表现为“全场一致”变化和“东西反向”变化两种特征,且均在2003年前后发生转折.(3)当青藏高原春季感热整体异常偏弱(强)时,中国北方上空高度场异常偏高(低),南亚高压偏弱(强),位置偏西(东),西北太平洋副热带高压异常偏弱(强),位置偏东(西),整层水汽通量辐合于华南(江淮和河套)地区,导致雨带偏南(北).“,”Based on the 70-station monthly surface Qinghai-Xizang Plateau sensible heat (QXPSH) data derived from the station observation data combined with the NASA-made normalized difference vegetation index (NDVI) data for the period of 1982-2012,the monthly summer precipitation data at 160 stations in the eastern China covering 1951-2012 and the monthly NCEP/NCAR Ⅰ reanalysis data,the spacial-temporal variability of the QXPSH and its influence on the later summer rain pattern over the eastern China are analyzed through statistical method including EOF,SVD,etc.Results from observation and reanalysis dataset show that:(1) In the 1990s,the Ⅲ rainfall pattern appears most times in China,and the eastern China experiences more frequent precipitation,especially regions along the Yangtze River.As the rainfall pattern shifts northward since the 21st century,the Ⅱ rainfall pattern began to increase.(2) Generally,the spring (March-May) QXPSH is strong in the west but weak in the east.The surface sensible heat flux is strongest in May and its interannual variability is most obvious.On the spatial evaluation,there are two patterns of “consistent change” and “east-west reverse change”,and they have a turnabout in 2003.(3) When the spring QXPSH is on its negative (positive) phase,the high (low) pressure anomalies over northern China,the weak (strong) South Asian high that located westward (eastward),and the water vapor flux diverges in the vicinity of South China (Yangtze River and Hetao River),it results in the rainfall pattern shifting southward (northward) in the eastern China.