洞庭湖区洪涝灾害的形成机制分析

洞庭湖区洪涝灾害的形成机制分析 Causing Mechanism Analysis of Flood and Waterlogged Disaster in Dongting Lake Region 毛德华 MAO De-hua~ 1 2 3 4 first-author 夏军 1 2 3 4 武汉大学水资源与水电工程科学国家重点实验室 武汉大学水资源与水电工程科学国家重点实验室 1,2), XIA Jun~ 1,2), XIA Jun~ 武汉大学水资源与水电工程科学国家重点实验室 湖北武汉430072湖南师范大学资源与环境科学学院 武汉大学水资源与水电工程科学国家重点实验室 湖北武汉430072湖南师范大学资源与环境科学学院 ,北京,100101 ,北京,100101 湖北武汉430072中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室 湖北武汉430072中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室 为搞好洞庭湖区洪涝灾害的预测和防灾减灾,促进湖区经济建设,本文对洞庭湖区洪涝灾害的形成机制进行了分析研究.结果表明:80 %特大洪涝灾害的发生在厄尔尼诺年的次年,其内在机制是厄尔尼诺事件所导致的全球气候异常.大气环流的异常是洪涝发生的根本原因,主要表现在有特大洪涝年汛期,位于110° 1 20°E的西太平洋副高脊线位置都稳定处于19° 2 4°N之间,且越过24°N的时间大致与城陵矶年最高水位出现时间相吻合;西风带形势稳定;印度低压偏强并持续稳定.洞庭湖区洪涝与湖区、四水流域、长江上游东部区和西部区等广泛地域的降水密切相关,汛期在这4个区域第一次大范围的强降水过程以后20 天各代表站降水量总和的平均值对洞庭湖的洪涝预测具有决定性意义. The causing mechanism of flood and waterlogged disaster in Dongting Lake region was studied in order that the flood forecast and disaster prevent and disaster reduction will be done well and economic construction will be promoted. The research results are as follows: The 80% of extreme flood and waterlogged disaster occurred at the next year to El Nino. The fundamental reason is the abnormal atmospheric circulation, which are as follows: In the flood reason of extreme flood and waterlogged year, the west Pacific Ocean subtropical ridge that locates among 110°-120°E locates stably among 19°-24°N,and the time that the ridge crosses the 24°N is approximately the same as the time that the annual highest water level in Chenglinji station appears; The westerlies situation is stable. Indian Low Pressure is more strong and sustainable stability. Flood and waterlogged relates to the precipitation among the Dongting Lake region,“four river” valley, east region of upper reaches, west region of upper reaches in the flood period, the sum average of representation station precipitation from the first day of large range heavy precipitating process to twentieth day in the four area is key factor to the occurrence of flood and waterlogged in flood period. 洪涝灾害 厄尔尼诺 大气环流异常 区域联系机制 洞庭湖区 flood and waterlogged disaster El Nino abnormal atmospheric circulation regional link mechanism Dongting Lake region X43 中国科学院知识创新工程重要方向项目（KZCX SW 317 03）;湖南省自然科学基金资助项目（01JJY3014） 2005-02-01 2021-04-01 2