2008年1月欧亚阻塞形势的ECMWF集合预报效果评估检验  

The assessment and verification of ECMWF ensemble forecasting on the Eurasia atmospheric blocking in January 2008

作　　者：王毅 金荣花 代刊 牛若芸 曹勇 

机构地区：[1]国家气象中心,北京100081

出　　处：《大气科学学报》2014年第3期257-267,共11页Transactions of Atmospheric Sciences

基　　金：公益性行业(气象)科研专项(GYHY200906007);国家科技支撑项目(2009BAC51B03)

摘　　要：基于欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)集合预报系统资料,评估和讨论了2008年1月我国南方发生严重冰冻雨雪灾害期间欧亚中高纬阻塞形势的预报效果。结果表明,2008年1月阻塞形势发生频率极端偏高,ECMWF集合预报的阻塞发生频率随着预报时效的延长逐渐降低。环流预报效果检验表明,预报时效大于6 d时,集合平均的预报效果好于确定性预报,因此集合预报的优势主要体现在中期预报时段。对阻塞形势的可预报性的分析表明,阻塞崩溃期间的可预报性低于阻塞建立期间。另外,通过集合预报可以获得阻塞发生的概率,从而提前为预报员提供可能发生阻塞的信号。Based on the ECMWF （European Centre for Medium-Range Weather Forecasts） globe ensemble Prediction System（EPS）,the forecasting performance on Eurasia blocking circulation in January 2008 when the freezing rain and snow storm occurred in South China were assessed and discussed.The results showed that the observed blocking frequencies during January 2008 were extremely high and the blocking frequencies forecasted by ECMWF decreased with the lead time increasing.The circulation forecasting verification showed that the performance of ensemble forecast was better than that of deterministic forecast when the lead time was longer than 6 days.So the advantage of ensemble forecast mainly lied in the mid-range forecast.The blocking predictability analysis indicated that the predictability during the decay stage was lower than that during the onset stage.In addition,the blocking occurrence probability can be obtained based on the ensemble forecast,and such information could be offered to the forecasters in advance.

关 键 词：阻塞形势 集合预报 概率预报 可预报性 

分 类 号：P456.2[天文地球—大气科学及气象学]