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1998年长江全流域大洪水的特点是洪峰频繁 ,洪水水位高 ,高水位持续时间长 ,异常降水是形成洪水的直接原因。 1998年降水异常是由于强厄尔尼诺事件使大气环流异常 ,导致西太平洋副热带高压位置偏南 ,暖湿空气与南下冷空气频繁在长江流域交汇 ,使长江流域大部频繁降大雨 ,同时中尺度强对流云团频繁发生导致暴雨 ,大暴雨和特大暴雨连续出现。最后 1998洪水带给人们的深刻反思。
The major floods in the whole Yangtze River basin in 1998 were characterized by frequent peak floods, high flood water level, long duration of high water level and abnormal precipitation as the direct cause of flood formation. The anomalous precipitation in 1998 was due to the abnormal atmospheric circulation caused by the strong El Niño event, which caused the position of the western Pacific subtropical high to be southward. The warm and humid air and the southward cold air frequently interfered in the Yangtze River basin, causing heavy rainfall in most areas of the Yangtze River. Meanwhile, The frequent occurrence of clouds caused heavy rain, heavy rain and heavy rain continued to appear. The last flood of 1998 brought profound introspection to people.