TIGGE降雨信息在柴河流域洪水预报中可利用性评估

Availability Assessment of TIGGE Precipitation Data in Flood Forecasting for Chaihe River Basin

基于全球多模式集合预报(TIGGE)资料,以柴河流域为研究区域,采用TS评分、Brier评分和Talagrand分布等方法对欧洲中期天气预报中心(ECMWF)、美国国家环境中心(NCEP)和英国气象局(UKMO)三个中心集合预报的6h、12h、24h短期降雨量进行定量评估和对比,并分别以实测降雨和NCEP预报降雨驱动新安江模型模拟洪水过程,据此探讨了集合降雨预报的可利用性。得到两个重要结论:ECMWF、NCEP和UKMO对低雨量级降雨的预报效果较好,各雨量级的预报效果有随预见期增长而增加的趋势,且普遍存在空报率较高、漏报率偏低的情况;集合降雨预报信息可应用于新安江模型进行洪水预报,并能够有效的延长洪水预报的预见期。研究成果可在适当条件下推广应用至其它流域的洪水预报作业中。

This study took the Chaihe River basin as the research area using the TIGGE data. The short-term precipitation of 6h ,12h and 24h from ECMWF, NCEP and UKMO were taken into quantitative evaluation and comparison by using the methods of TS score, Brier score and Talagrand distribution. And then the Xinanjiang model was driven to simulate the flood process with the actual rainfall and NCEP rainfall forecasting respectively. The availability of ensemble forecast was discussed and the results show that： （1） The ECMWF, NCEP and UKMO are better for rainfall forecast with low precipitation, and the forecast effect of each rainfall level increases with the forecast period, and in general, the empty reporting rate is higher than the omissive judgement rate. （2） The data of ensemble forecast can be applied to the flood forecast of Xinanjiang model, and can effectively extend the forecast period of flood forecast. Therefore, the research results could be applied to flood forecasting in the other basins.