摘要: |
该文应用TS评分、预报偏差(BIAS)等方法,对ECMWF模式预报的2015年12月—2018年12月岳阳市降水场资料,开展晴雨和分级降水检验。晴雨预报检验结果表明:ECMWF模式对岳阳市晴雨预报性能总体较稳定,年际变化幅度较小;晴雨预报准确率季节差异大,冬季最高,秋季次之,夏季最低;从逐月晴雨预报检验来看,12月份最高,8月最低;晴雨预报还存在明显的日变化规律,对夜间的预报能力明显优于白天;空间上总体呈北高南低的空间分布特征。分级降水预报检验结果表明:小雨量级降水预报评分明显高于其他量级降水,中雨次之,大雨及以上量级评分较低且无明显规律;小、中、大雨3个量级任一时效的空报率整体上比漏报率大,小雨量级表现得尤为明显,说明小雨量级的空报更为严重。针对小雨降水预报空报率高的现象,该文对岳阳市ECMWF模式预报降水量1.2 mm以下消空处理后进行了预报释用,结果表明:冬季订正空间较小,夏季各时效可适度订正;春季和秋季可视情况适度订正,订正后可以有效提升预报技巧,但增加了一定漏报风险。 |
关键词: ECMWF模式;降水量;检验;晴雨;降水分级 |
DOI: |
投稿时间:2019-09-17 |
基金项目:湖南省气象局2020年预报员专项(XQKJ20C001):岳阳市ECMWF数值模式降水预报检验与释用 |
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Verification and Interpretation of Precipitation Forecasted by ECMWF Model in Yueyang City |
CHEN Jiaorong,CAO Xianglin,XIAO Ping |
(Yueyang Meteorological Bureau, Yueyang 414000 ,China) |
Abstract: |
The forecast data of ECMWF numerical model precipitation field in Yueyang city from December 2015 to December 2018 were tested by TS scoring, forecast BIAS and other methods,the precipitation tests of clear rain and graded rain were carried out. The Verification results of clear rain show that the ECMWF model has a stable performance in Yueyang city, with a small range of annual variation. There is a big difference between seasons. The accuracy of clear rain in winter is the highest, followed by that in autumn and the lowest in summer. From the monthly clear rain test, the highest accuracy was in December and the lowest in August. There are also obvious diurnal variation rules in the forecast of clear rain. On the whole, it shows the spatial distribution characteristics of becoming increasingly lower from north to south. The results of grading precipitation forecast test show that: light rain scale precipitation forecast score is obviously higher than other orders of precipitation, moderate rain followed, for heavy rain and above, the score is lower and has no obvious rule. The false alarm rate of small, medium and heavy rain is larger than the rate of missing report on the whole, and the false alarm of light rain is particularly obvious, indicating that the false alarm of light rain is more serious. In view of the phenomenon of high false prediction rate of light rain precipitation forecast, this paper applied the forecast of ECMWF model in Yueyang city after the air elimination treatment of 1.2mm or less precipitation forecast. The results show that the correction space is small in winter and the aging of summer can be corrected moderately. In spring and autumn, it can be revised appropriately, which can effectively improve forecasting skills, but increase the risk of underreporting. |
Key words: ECMWF model;precipitation;test;clear rain;precipitation classification |