洪水预报模型输入与输出的误差分布及相关性分析

Analysis on Error Distributions of Input Data and Output Data of Flood Forecasting Model and Its Correlation

降雨预报信息作为洪水预报模型的输入,该信息的准确性直接影响洪水预报模型输出的准确性。为探究模型输入(降雨预报)误差与输出(洪水预报)误差之间的关系,以英那河流域为例,分析了不同雨量等级下,预报模型的输入误差与输出误差的分布规律,并定性分析了两种误差的相关关系。结果表明,降雨量等级若为无雨及小雨时,两种误差不相关;若为中雨及以上量级时,两种误差中等相关。基于误差分布规律和相关性分析结果,给出不同置信水平下,输入与输出的相关误差域,定量地描述了两种误差的相关关系。本研究方法可为洪水预报方案研究和水库防洪预报调度方式的可行性分析服务,并为防洪调度决策的风险分析提供依据。

The rainfall forecast information as the key input data of the flood forecasting model has a great effect on the output data.To explore the relationship between input and output errors,this paper analyzed the distribution of input error(rainfall forecast error)and output error of flood forecasting model under different amounts of rainfall and its correlation in the Yingna River basin.The results show that the two errors are uncorrelated when rainfall grades are no rain and light,and while they are positive correlation when rainfall grade is moderate above.Besides,the correlation error domain between input error and output error under the different confidence levels is obtained by using the confidence estimation method.The research method can serve for the study of flood forecasting scheme and the feasibility analysis of reservoir flood control forecasting operation method,and provide a basis for risk analysis of flood control operation decision.