基于预报难度的径流预报水平综合评定

Forecast difficulty-based comprehensive evaluation of runoff forecast levels

本文在分析传统径流预报精度评定方法的基础上,给出了预报难度的概念和定义,并考虑有无降雨、不同预见期及不同预报流量级别等不同预报情景,提出了两种基于预报误差分布的预报难度计算方法,可实现不同预报情景及不同预报水平标准下的预报难度计算。将其与预报员预报水平评估相结合,建立了考虑预报难度的预报人员综合预报水平评定方法。实例研究结果发现,相比于传统方法,所提综合预报水平评定方法能有效考虑不同预报情景的预报难度,能够充分体现出大难度预报情形(例如长预见期预报)在预报精度提升时对于综合预报水平的贡献量,使所得结果更加科学、合理,可有效促进预报人员预报水平的自我提升。

This paper describes a concept of forecast difficulty and its definition based on analysis of traditional evaluation methods of river runoff forecast levels,and develops two methods for its calculation using forecast error distributions and considering various forecast situations such as different rainfalls,forecast lead times and inflows.These methods can achieve effective calculations of forecast difficulty in various forecast situations under different standards of the forecast levels;and by combining them with evaluation of the forecasters’levels of runoff forecasting,we work out a comprehensive method for evaluating the forecasters’levels that takes into account of the forecast difficulty factor.A case study shows that compared with traditional methods,our comprehensive evaluation method is effective in considering various forecast difficulties in different forecast situations.And it can fully reflect the contribution of difficult forecast situations(such as long lead time)to the comprehensive forecast level;and provides more accurate,scientific and reasonable evaluation of runoff forecast levels,thus effectively promoting the forecasters’self-improvement of forecast levels.