1997年江淮梅雨的分析

１９９７年江淮梅雨姗姗来迟，汉品以东的长江中、下流地区和江淮流域梅雨量偏少４－５成，对照历史上５０年江淮梅雨资料分析：１９９７年梅雨，属迟梅、旱梅。作者通过对西太平洋副热带高压、西风带环流特征的分析，认为１９９７年具有历史上同类迟梅、旱梅的环流特征；并应用４０年长江中、下游地区梅雨总量Ｍ值（梅雨旱、涝指数）的非整数波动率谱的分析，１９９７年梅汛期出现旱是符合Ｍ值周期演变规律的，对梅雨期副热带高压的

ANALYSIS OF MEIYU OVER JIANG-HUAI VALLEY IN 1997

Meiyu was late to arrive over Jiang-Huai in 1997. Its precipitation reduced by 40-50 per cent in this area on the east of Hankou,compared with the data about Meiyu in the past 40 years. Therefore,it was a late and dry Meiyu. The circulation of Meiyu in 1997 had the same characters as those in the past late and dry Meiyu circulation by the analysis of west Pacific subtropic high and westerly belt circulation. In addition,by the analysis of non- integer wave power spectrum in the past 40 years' total amount of Meiyu precipitation's M value (Meiyu drought index and Meiyu flood index),it was found that the drought appeared in A4eiyu flood of 1997 accorded with the periodic evolution rule of M value. The forecast about the subtropic high's three-time north jumping)once south Moving during Meiyu sea- son and the And-forecast of T_(106) were successful which offers enough helps for decisions.