改进的ECMWF集合预报融合产品在海河流域的检验与分析

利用2012—2015年5—8月欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)集合预报在海河流域的17个降水统计量产品与对应降水实况的TS评分检验结果,设计了适合该地区的多种统计量融合技术改进方案,并对新方案进行试验评估。4个月(2016年5—8月)的逐日试验分析结果显示:对于36 h预报时效,与国家气象中心下发的产品相比,改进后的融合产品在5个降水量级的TS评分上均有一定程度提高,降低了暴雨以下量级降水的漏报率,同时消除了大暴雨的虚报区;对于60 h和84 h预报时效,改进后的产品对大雨及以下量级降水的TS评分均有所提高,降低了大雨及以下量级降水的漏报率。新方案更符合海河流域夏季降水特点,提高了该地区降水预报准确率。

Verification and Analysis of Improved ECMWF Ensemble Forecast Fusing Product in Haihe River Basin

Based on the TS score results of 17 statistical products of European Centre for Medium Range Weather Forecasts (ECMWF) ensemble forecast and the corresponding real precipitation data in the Haihe River basin from May to August during 20122015, a new scheme of multi statistic fusion technology for this region is designed and estimated. After 4 mouths (MayAugust, 2016) experiment, the results show that for the 36 h forecasting time, the TS score of the improved fusing product is higher than the product issued by the National Meteorological Center at all 5 precipitation levels, which reducing the missing rate of rainfall below the level of rainstorm and the false alarm rate of the heavy rainstorm. For the 60 h and 84 h forecasting time, the TS score of the improved fusing product has increased at the level of heavy rain and below, by reducing the missing rate of these rainfall. The new scheme is more suitable for the characteristics of summer precipitation in Haihe River Basin, and could improve the forecast accuracy of precipitation.