近10年我国降水的QBO分析

QBO ANALYSES OF PRECIPITATION IN CHINA FROM 1986 TO 1995

近１０年来我国东部地区降水分布趋势的年际变化具有ＱＢＯ特征，双年的降水为中部地区少南北多，单年的降水为中部多南北少，其中江淮流域的降水变化最明显．分析表明，降水ＱＢＯ的特征与西太平洋副高和冷空气活动有关，一般双年副高偏北、亚洲纬向环流发展，雨带偏北；单年相反，副高偏南、亚洲经向环流发展，雨带偏南，江淮流域降水较多．

During the last ten years, the interannual changes of the precipitation distribution tendency in eastern China are characteristic of QBO. The precipitation in even numbered years is more than normal in central China, and less in northern and southern areas whereas the precipitation in odd numbered years is contrary, more precipitation in the central area, and less in northern and southern parts. The feature of precipitation change in Changjiang Huaihe River basin is the most obvious. The analyses show that QBO feature of precipitation has relations with West Pacific subtropical high and cold air actions. Generally in the even numbered years, subtropical high is to the north of its normal position, the zonal circulation of Asia develops, and corresponding rain belt maves northward. The condition for odd numbered years is contrary, the subtropical high is southward, meridional circulation of Asia develops, and the rain belt moves southward, the precipitation in Changjiang Huaihe River basin is more than normal.