新型降水分布数学模型研究及其应用

A new precipitation distribution hydrological model and its application

在分布式水文模型中 ,单元栅格内的降水输入是准确模拟各种水文过程的关键因素 ,寻求产生分布式降水数据的方法是水文模型研究的热点之一 .在对国内外降水模型分析基础上 ,认为流域面上实际降水分布是天气系统降水与下垫面地形影响共同作用的结果 ,如果不受地形影响 ,天气系统降水的降水量等值线在平面上的分布近似为一组同心椭圆 .根据这一原理 ,建立了一种能够模拟天气系统降水分布 ,并利用牛顿插值法对模拟结果进行地形影响修正的新型降水分布数学模型 ,提出了对降水中心位置及其中心降水量的模型模拟 .利用黄土高原西川河流域实测资料对模型进行了检验 ,结果表明 ,该模型具有较高精度 .由于模型概念简单明晰 ,且能指明降水中心位置及其中心降水量 ,因此在流域暴雨分析和洪水预报中具有一定价值 .

In distribution hydrological models,precipitation is the key input data for analyzing and computing hydrological processes.Finding a way to produce distribution precipitation data is a hotspot in hydrological research.This paper presented the hypothesis that the distribution of precipitation on the earth surface is the result of the effects of atmosphere system and terrain.Moreover,the spatial distribution of natural precipitation is a group of concentric ovals on the flat earth surface,and has a definite centre with maximum precipitation not affected by terrain.Supporting by the hypothesis,this paper established a new precipitation distribution hydrological model which could simulate the spatial distribution of precipitation,and modified the terrain effect on precipitation through Newton interpolation.The position of the precipitation centre and its precipitation amount were simulated in first time,and thus,the model could have a practical value in basin storm analysis and real time runoff forecasting.The model was tested by the precipitation data of the Xichuan river basin in the Loess Plateau,which indicated that the model had a high precision.