Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capac...Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capacities are low, and therefore flood hazard is grave. In this paper, taking the Yongjiang basin in southeast China as an example, the approaches and methods of geographic information system(GIS) applied to flood disaster control and reduction research on small basin are explored. On GIS help the rainfall runoff calculation model and the river channel flood routing model are developed. And the evaluating flood submerged area and the damage assessment models are built supported by digit elevation models. Lastly the decision support system on GIS supported for flood control in research basin has been set up. This greatly improves flood proofing decision making capacities in river basin, and provides valuable information and a mode for flood prevention and reduction in the medium and small basin. Meanwhile, the research indicates that technologies of GIS provide a powerful tool for flood disaster control.展开更多
文摘Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capacities are low, and therefore flood hazard is grave. In this paper, taking the Yongjiang basin in southeast China as an example, the approaches and methods of geographic information system(GIS) applied to flood disaster control and reduction research on small basin are explored. On GIS help the rainfall runoff calculation model and the river channel flood routing model are developed. And the evaluating flood submerged area and the damage assessment models are built supported by digit elevation models. Lastly the decision support system on GIS supported for flood control in research basin has been set up. This greatly improves flood proofing decision making capacities in river basin, and provides valuable information and a mode for flood prevention and reduction in the medium and small basin. Meanwhile, the research indicates that technologies of GIS provide a powerful tool for flood disaster control.
文摘数值气象预报与水文模型相结合能有效延长洪水预报的预见期,对中小流域山洪预警具有重要意义。为了研究高分辨率数值气象预报模式在中小流域洪水预报中的应用潜力,以福建省桃溪流域为研究对象,评估了数值气象预报模式GRAPES-RAFS(Rapid Analysis and Forecast System)在不同起报时刻的短期降雨预报能力,采用两种偏差校正方法(线性放缩法(LS)和分位数匹配法(QM))对降雨预报数据进行偏差校正处理,并分别用校正前和校正后的数据驱动新安江模型,评估预报降水在场次洪水预报中的适用性。评估结果表明,GRAPES-RAFS中小流域降雨过程具有较好的预报能力,但高估了降雨量,所有评价指标具有较好的一致性;采用两种偏差校正方法均能显著降低降雨预报的偏差,12场降雨的平均相对偏差从60.33%分别降低至18.00%(LS方法)和21.33%(QM方法);未经校正的GRAPES-RAFS预报降雨直接用于洪水预报的效果表现不佳,洪峰被明显高估,但降雨偏差校正能显著提升洪水预报的精度。总体而言,偏差校正后表现较好的降雨场次对应表现较好的洪水场次,且两种偏差校正方法表现相近。
