ECMWF集合预报产品在河南省暴雨预报中的应用

Application Research on Heavy Rainfall of ECMWF Ensemble Prediction in Henan Province

对2014到2015年5—8月欧洲中期天气预报中心(ECMWF)的9类与降水相关的集合预报基本产品和统计量(以下简称集合预报产品)进行暴雨TS评分检验,筛选出:%90分位数、最大值、控制预报、融合产品、概率匹配平均5个评分较高产品.对所选产品做暴雨过程的应用效果分析发现:5个集合预报产品的强降水中心位置预报与实况较接近,大部分产品对大雨以上降水落区预报与实况较接近,但存在强降水中心极值预报较实况偏小的不足;最大值产品对于暴雨落区范围和强降水中心极值的预报通常较实况偏大;5个集合预报产品均表现为0~72 h时效内预报效果最好,72 h之后各产品对暴雨的预报能力明显减弱.基于检验和分析结果,采用百分比权重集成技术建立暴雨预报方法,2016年业务应用结果表明,集成后的暴雨预报产品效果优于单个集合预报产品.

According to the heavy rainfall forecast of TS score verification results in the European Centre for Medium Range Weather Forecasts（ECMWF）9 ensemble forecast products and basic statistics are related with precipitation from May to August in 2014 and 2015,5 products are selected which have higher scores of %90 quantile,maximum,control,statistic fusing and probability matching products. The application effect of heavy rainfall process analysis shows that the prediction position of the strong precipitation center of the 5 forecast products is closed to the observations. The area of precipitation over heavy rain is similar to observations in most products,while the prediction value of extreme heavy rain is smaller than observations. The maximum forecast product for the area of heavy rainfall and the value of extreme heavy rain are usually larger than observations. The 5 ensemble forecast products show the best prediction effect within 0 h to 72 h,while the forecast ability of the products are obviously weakened after 72 h. Based on the results of verification and analysis,the method of percentage weight integration is used to establish the heavy rain forecast method. The application results in 2016 show that the integrated heavy rain forecast products are better than the single ensemble forecast product.