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基于太湖流域1950-2003年洪旱灾害等级序列及相应气候指数,采用改进的Mann-Kendall检验、小波分析等方法,研究流域洪旱灾害与东亚夏季风的变化及其相互联系.结果表明:太湖流域在20世纪80、90年代洪灾加剧,原因在于东亚夏季风在70年代末以来呈减弱的趋势,使梅雨期长度和雨量增加.近50a太湖流域洪旱灾害频谱结构发生变化,从以年代际振荡成分为主减弱为以年际变化为主,即变化周期在逐渐变小,同时东亚夏季风指数也发生了类似的变化.流域洪旱灾害与东亚夏季风之间的联系,在70年代以后强于70年代以前,二者反位相关系以1975-1985年左右最为显著.
Based on the series of flood and drought disasters in the Taihu Lake Basin from 1950 to 2003 and their corresponding climatic indices, the authors used improved Mann-Kendall test and wavelet analysis to study the relationship between flood-drought disasters and the East Asian summer monsoon and their interdependence. The results show that: Floods intensified in the basin in the 1980s and 1990s due to the declining trend of the East Asian summer monsoon since the late 1970s and an increase in the length and amount of rainfall during the rainy season. The spectral structure of the flood and drought disasters in the Taihu Lake basin changed in the past 50 years. From the interdecadal The oscillation component is mainly weakened by interannual variation, that is, the change period is gradually getting smaller, while the East Asian summer monsoon index also has similar changes. The relation between flood and drought disasters in the basin and the East Asian summer monsoon, after the 1970s Prior to the 1970s, the anti-phase relationship between the two was most pronounced around 1975-1985.