三峡水库水文气象预报不确定性及误差分布分析

准确、及时的水文气象预报信息是水库实时预报调度的基础和技术支撑。基于长江水利委员会水文局发布的三峡水库历年短中期入库流量预报成果，综合评定了预报精度和水平，分析了降雨量级、落区及入库流量级别等因素对预报误差的影响，比较了正态分布和非参数估计两种方法用于估计预报相对误差概率密度函数的效果。结果显示，采用非参数估计推求的概率密度函数与样本拟合程度高，可应用于三峡水库水文气象预报定量风险管理。

Analysis of hydro-meteorological forecasting uncertainty of Three Gorges Reservoir and error distribution

Accurate and timely hydro-meteorological forecasting information is the basis and technical support of real-time forecast-based operation of the reservoir. Based on the historical short-term and medium-term inflow forecast of Three Gorges Reservoir issued by Bureau of Hydrology, Changjiang Water Resources Commission, the inflow forecasting accuracy are evaluated comprehensively, the influences of the precipitation magnitude, precipitation area and inflow grade on forecasting error are analyzed, and the performance of the normal distribution and the nonparametric estimation method in estimating the probability density function of relative error is compared. The results showed that the nonparametric estimation method has high fitting degree in estimating the probability density function of forecasting relative error, and the comprehensive analysis results can be applied to the quantitative risk management of Three Gorges Reservoir.