NCEP集合预报系统在亚欧和北美区域的预报效果对比  

Comparisons on forecast performance of NCEP ensemble prediction system between Eurasia and North America regions

作　　者：段明铿[1] 王盘兴[1] 李驰钦[1] 

机构地区：[1]南京信息工程大学气象灾害省部共建教育部重点实验室,江苏南京210044

出　　处：《大气科学学报》2012年第6期641-651,共11页Transactions of Atmospheric Sciences

基　　金：国家自然科学基金资助项目(41205083);公益性行业(气象)科研专项(GYHY(QX)200906014;GYHY(QX)200906007);江苏高校优势学科建设工程资助项目(POPD)

摘　　要：使用NCEP集合预报系统(EPS)输出的500hPa位势高度场预报资料和相应的NCEP/NCAR再分析资料,针对集合平均预报和概率预报,采用多种预报效果检验评价方法,对该系统在亚欧和北美区域的预报效果进行全面的分析比较。总体而言,NCEP-EPS对亚欧区域的环流集合预报效果不亚于其对北美区域的预报效果。1)ACC检验表明,亚欧区域的集合平均预报效果在除冬季外的三个季节都明显优于北美区域,可用预报的时效相差达0.6～1d,且夏季的差别最大。RMSE检验表明,亚欧区域的预报效果在四个季节里均优于北美区域。2)集合概率预报可靠性的季节差别不明显,均为预报时效较短(长)时,北美(亚欧)区域的可靠性更好。系统对亚欧区域的事件识别范围相对较小,但其预报可靠性较高,北美区域则正好相反。3)夏季亚欧区域的集合概率预报效果明显优于北美区域,秋季和冬季北美区域的预报效果较好,春季在预报时效小于5d时北美区域占优,而其后则是亚欧区域的预报分辨能力更好。Based on the forecast dataset of 500 hPa geopotential height fields from NCEP ensemble prediction system（EPS） and the corresponding NCEP/NCAR reanalysis dataset, the ensemble forecasting performance in Eurasia region （EA） is compared with the performance in North America region （NA）. By several forecast verification and evaluation methods, the comparisons focus on the ensemble mean forecasts and ensemble probabilistic forecasts. In general, the NCEP-EPS circulation ensemble perform- ance in EA is nothing less than the prediction in NA. 1 ） ACC shows that, except in winter, the ensemble mean forecasts in EA in the other three seasons are clearly superior to those in NA, and their difference of maximal lead time of useable forecasts is 0.6-1 d, with the largest difference in summer. RMSE shows that the forecast results in EA in the four seasons are better than those in NA. 2） The seasonal differences of reliability of ensemble probability forecasting are not evident. For the shorter （longer） lead time, the reliability in NA （EA） is better. The identification range of synoptic events in EA is rela- tively smaller, but the reliability is relatively higher in the region. This conclusion is opposite in NA. 3 ） In summer, the ensemble probability predictions in EA are clearly superior to those in NA. In autumnand winter, there are better results in NA. In spring, when the lead time is less than 5 d, the results in NA are better, but when it is more than 5 d, there is better forecasting resolution in EA.

关 键 词：集合预报 NCEP 亚欧区域 北美区域 预报效果 

分 类 号：P457.6[天文地球—大气科学及气象学]