摘要
降水是影响流域水循环最活跃的因素,其时空分布不均匀对流域产汇流的影响非常大,因此在进行流域水文模拟时,需要充分考虑到降雨的时空变异性。本文针对大尺度流域的特点,提出了一种日雨量的空间展布方法,该方法根据站点降雨量之间的相关系数选取参证站点,采用距离平方反比法把站点的日雨量插补到空间计算单元上去,或采用泰森多边形法插值。该方法计算结果和本次全国水资源规划的结果差别不大,说明插值方法比较可靠。由于大尺度流域雨量站点的布设比较稀疏,采用空间插值的方法生成计算单元降雨量值精度不好,本研究中提出了一个大于10mm的大强度日降雨的向下尺度化方法。首先建立了一个将日降雨分配成小时降雨量的雨强历时关系模型：然后根据黄河流域的特点,把全流域划分为五个大强度降雨区,分区对参数进行了率定：最后采用实测资料对模型进行了检验。本文提出的方法,在黄河流域水文模拟中进行了应用,由径流模拟结果看,效果令人满意。
Precipitation is the most active factor influencing basin water cycle. The inhomogeneous spatial and temporal distribution of precipitation has great influence on basin runoff. Therefore, the space-time variabihty of precipitation should be fully taken into consideration when the process of basin water cycle is simulated. This paper introduces a spatial interpolation method of daily precipitation in large-scale basin. According to the method, the reference rain gauges are selected with correlativity. If there exists the reference rain gauges significant in correlativity, the Reverse Distance Square （RDS） method is adopted to interpolate the precipitation. If not, the Thiessen polygon method is adopted. The interpolation result is compared with the result of the Countrywide Water Resources Planning in the progress. The difference is not too much which shows that the interpolation method presented in this paper is credible. Because rain gauges are sparely distributed in large-scale basin, the generated precipitation of every unit is not so good if the spatial interpolation method is adopted. A method of daily precipitation whose value is more than 10 mm is presented. The relation model of precision of downscaling precipitation intensity and duration is developed which can generate hourly precipitation from daily data. According to the characteristics of precipitation in different parts of the Yellow River Basin, the basin is divided into five districts. The parameters of the model are calibrated and the model is validated with measured data in respective districts. The method has been applied in hydrological simulation in the Yellow River and is proved to be satisfying by comparing the generated data with the measured data.
出处
《水文》
CSCD
北大核心
2006年第1期6-11,共6页
Journal of China Hydrology
基金
国家自然科学基金(50239050)
黄委会"十五"治黄重大科技项目(2002202)
中国水利水电科学研究院
国家重点基础研究(973)发展规划项目第二课题"黄河流域水资源演变规律与二元演化模型"(G1999043602)项目报告
2004.9
关键词
大尺度流域
降雨
空间插值
日降雨向下尺度化
large-scale basin
precipitation
spatial interpolation
downscaling daily precipitation
