摘要
基于SWCWARMS模式9km×9km分辨率逐小时降水预报,通过时间滞后集合预报方法构建多个集合成员,使用SAL评分值计算相应集合成员的权重系数,进行不等权集合平均,从而得到新的逐小时降水预报。利用SAL、TS和BIAS检验方法对四川省2019年8月的逐小时降水量时间滞后集合预报及相应的SWCWARMS模式最新时次预报进行对比分析,结果表明:(1)时间滞后集合预报SAL检验的L值和A值都较模式预报更接近于0,较好地改善了降水位置和强度的整体预报水平;(2)时间滞后集合预报对逐小时降水晴雨TS评分提升明显,评分提高百分率在10%左右,有效地减小了模式在晴雨方面的空报;(3)临近预报时效,时间滞后集合预报方法对于大量级降水预报也有较好的订正效果。
Based on the hourly precipitation from the 9 km ×9 km resolution SWCWARMS model,ensemble members are formed by the time-lagged ensemble forecast method.A new hourly precipitation forecast is obtained from the ensemble average of differential weights,which are calculated by the SAL scores of ensemble members.This study verified the time-lagged ensemble and the model up-to-date forecast of hourly precipitation in Sichuan from 1 to 31 August 2019 by the SAL,TS and BIAS evaluation method.The results show:(1)The time-lagged ensemble method led to improvement on the overall level of the rainfall intensity and location forecast.The values Land Aof SAL scores were both closer to 0.(2)The clear-rain TS score of time-lagged ensemble forecast was higher,and the percentage increase was about 10%.The method can reduce the false alarm of rain forecast.(3)In the lead time of nowcasting,the improvement of the high intensity precipitation forecast was also obvious.
作者
张武龙
王彬雁
陈朝平
冯汉中
ZHANG Wulong;WANG Binyan;CHEN Chaoping;FENG Hanzhong(Sichuan Provincial Meteorology Observatory,Chengdu 610072;Heavy Rain and Drought-Flood Disaster in Plateau and Basin Key Laboratory of Sichuan Province,Chengdu 610072)
出处
《气象科技》
2021年第4期561-568,共8页
Meteorological Science and Technology
基金
四川省重点实验室项目(省重实验室2018-重点-06、SCQXKJZD2019001、SCQXKJZD202101-3)
中国局预报员专项(CMAYBY2020-110)
中国局气象关键技术项目(YBGJXM(2020)2A-14)共同资助。
关键词
时间滞后
不等权集合
小时降水量
SAL检验
time lag
unequally weighted ensemble forecast
hourly precipitation
SAL evaluation
