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利用1948-2008年NCEP/NCAR再分析风速资料,分析了亚洲副热带200hPa西风带急流（下称西风急流）时空变化的气候特征及其与我国江淮流域梅雨期降水和新疆夏季降水的关系。结果表明：（1）由冬入夏时,西风急流轴由30°N左右北进到45°N左右,中间有两次明显的快速北进,分别发生在4月和6～7月;由夏入冬时,急流轴再由45°N左右南撤至30°N附近。急流轴在北进过程中以90°E处出现最早,也最明显。（2）一年之中,西风急流中心主要位于西太平洋上空140°E处,只有两个月左右的时间停留在亚洲大陆上空。急流中心在6月中旬开始迅速西移,6月下旬移至江淮流域上空,7月底到达新疆天山地区上空,8～9月东退至冬季平均位置140°E左右。（3）江淮流域梅雨期的降水量与西风急流的位置有一定相关关系。若某年1月急流中心异常偏西,4～5月急流轴又异常偏南,则该年可能为丰梅年,江淮地区易出现暴雨洪涝灾害;否则相反。（4）盛夏季节新疆上空急流的强度及纬度位置与新疆降水也有一定关系。若某年4月中旬～5月下旬新疆和中亚地区西风急流轴明显偏北,该年夏季急流轴又偏南,且急流偏强,则新疆多雨;否则相反。“,”To better explore and understand the activity features of Asian Upper Westerly Jet（AUWJ） and their application to the weather forecast,the climatic features of pentad-to-pentad activities of AUWJ and their relationship with precipitation in partly areas of China were analyzed utilizing the 200 hPa wind speed of the NCEP/NCAR reanalyzed data from 1948 to 2008.The main conclusions are as follows：（1） The AUWJ moves northward from 30°N to 45°N from winter to summer;then southward back to 30°N again after summer.When moving northward,there are two fast-moving periods especially at the longitude about 90°E,one is from mid-April through the end of May,and the other is from June to July.The latter period corresponds to the Meiyu period in Changjiang-Huaihe River（CHR）.（2） The center of AUWJ usually stays at about 140°E for majority time of the whole year,while it moves quickly westward in mid-June;it moves to the upper of CHR in late June and Tianshan region of Xinjiang in the end of July,and then it moves eastward quickly back to 140°E again.It stays at the Asian continent just for about two months every year.（3） There is certain relationship between the AUWJ center latitude position and precipitation in CHR during the Meiyu period.Averagely,when the AUWJ center position is more westerly than normal in January,and the AUWJ axis is more southerly from April to May,it may be heavy Meiyu in CHR;vice versa.（4） There is also certain relationship between the strength and latitude position of AUWJ and the precipitation in Xinjiang in summer.When the AUWJ axis over Xinjiang is more northerly from mid-April to late May,and the axis is more southerly and AUWJ is stronger than normal in summer,the precipitation of Xinjiang in summer will be more than normal;vice versa.