基于动态临界雨量的山洪预警方法研究与应用

摘要

A flash flood early warning method based on dynamic critical precipitation is proposed in this pa-per.The method calculates soil moisture saturation using the Xin’anjiang model,then sets up forewarning discriminant functions for three time-scales,6 h,12 h and 24 h,using Widrow-Hoff algorithm of minimum mean square error criteria,and based on soil moisture saturation and maximum 6 h,12 h and 24 h precipi-tation before each flood event.With this method,together with rainfall data of the 17 flood events occur-ring during the period from 2003 to 2009 ,wich are obtained at precipitation stations in Pihe Basin parame-ters for the model are calibrated and the method is applied in 10 historical flash flood events to verify the three time-scale forewarning discriminent functions.The correct forecast rate is over 70%,demonstrating that the method is reliable and can be used to flash flood forecasting and early warning.%以新安江模型为基础，提出了考虑土壤含水量饱和度的动态临界雨量山洪预警方法。该方法采用新安江模型计算流域的土壤含水量饱和度，根据土壤含水量饱和度以及山洪发生前6、12和24 h等3个时间尺度的最大降雨量，应用基于最小均方差准则的 W-H （Widrow-Hoff）算法分别建立3个时间尺度的山洪预警动态临界雨量判别函数。利用该方法，结合淠河流域2003-2009年地面雨量站降雨资料以及17次典型洪水过程资料，率定了新安江模型参数，并用10次历史个例对所建立的3个时间尺度的山洪预警动态临界雨量判别函数进行了应用检验，山洪预警合格率超过了70％，表明该方法用于山洪预警是可行的。