2010年汛期多模式对山东降水预报的检验

Precipitation verification of multiple models during flood season of 2010 in Shandong province

为提高数值预报模式在山东汛期降水的预报能力,为降水预报及模式物理参数方案选择和调整提供客观依据,对2010年汛期(6—9月)山东区域MM5、WRF-RUC(WRF快速循环同化系统)和T639模式24 h、48 h累积降水预报产品,进行晴雨、一般性降水和分量级降水TS评分及平均绝对误差、平均误差分析。结果表明:从晴雨预报准确率来看,3种模式相差不大;一般性降水和小雨预报,MM5模式评分结果最差,T639模式预报效果最好;中雨以上量级,24 h降水T639模式预报效果最好,特别是24 h大暴雨评分T639模式为10.37%;而48 h降水T639模式预报效果下降明显。无论24 h降水还是48 h降水,除9月WRF-RUC模式平均绝对误差最小外,6—8月T639模式平均绝对误差均为最低,WRF-RUC模式24 h和48 h降水各月平均误差均为负偏差;不同的降水预报检验方案和天气过程类型对检验结果有一定的影响。

In order to improve the precipitation prediction accuracy of numerical model during flood season in Shandong province and provide scientific references for selection and adjustment of physical parameter schemes of models,the mean absolute error, mean error, TS score of 24 hours and 48 hours precipitation simulated by the MM5,WRF-RUC and T639 models under sunny/rainy weather, general precipitation, grading precipitation condi- tions were analyzed during flood season（ from June to September） of 2010. The results show that the accuracies of precipitation prediciton are similar for three models. TS scores of general precipitation and light rain are the lowest for the MM5 model and the highest for the T639 model. TS score of 24 hours precipitation prediction of middle rain and heavy rain etc. is the highest and that of heavy rain reaches 10. 37% for the T639 model,while that of 48 hours precipitation forecast decreases significantly. Weather 24 hours or not 48 hours precipitation forecast, the mean absolute error is the lowest in September for the WRT-RUC model and from June to August for the T639 model, while the monthly mean absolute error is negative for the WRT-RUC model. Diffident precipitation verifica- tion schemes and weather processes of diffident types have certain impacts on the verifications results.