利用近30年的NCEP再分析格点资料及中国站点降水资料,从降水、湿度、风场、水汽输送等角度研究了东亚夏季风边缘带的气候特征及其与华北、西北降水的关系。结果表明,降水场、比湿场、风场、水汽输送场所描述的东亚夏季风边缘带位置基本一致,大致沿西南-东北走向自西向东经过黄河上游-河套-华北北部-东北。夏季风边缘带附近的夏季降水年际变化较大,且夏季降水量与季风强度呈正相关。当夏季风影响到西北、华北北部时,西北、华北夏季降水偏多;反之则偏少。

Using the NCEP/NCAR reanalysis data and observatory station rainfall data in recent 30 years,the climatic features of boundary belt for east Asian summer monsoon and its relation with rainfall of North China and Northwest China are discussed based on rainfall,humidity,wind field,moisture transport,etc.Results show that the boundary belt roughly southwest-northeastly locates along the upper- and middle-reaches of the Yellow River,north part of North China and Northeast China.The summer rainfall along the belt has comparatively large interannual change and the rainfall amount positively correlates with the intensity of summer monsoon.More summer rainfall occurs over Northwest China(north part of North China) when summer monsoon reaches the Northwest China(north part of North China),and vice versa.