高原气象2026，Vol.45Issue(4)：1027-1043,17.DOI:10.7522/j.issn.1000-0534.2025.00119
川西高原夏半年数值模式降水预报分区分型精细化检验评估
Regional and circulation-type based fine verification of numerical model precipitation forecasts over the Western Sichuan Plateau in the warm season
摘要
Abstract
To evaluate the performance of numerical weather prediction(NWP)models over complex terrain and improve warm-season(May-October)precipitation forecasting over the Western Sichuan Plateau,this study assesses four models—ECMWF,CMA-GFS,CMA-MESO,and SWC-WARR—using 116 heavy rainfall events during 2022-2024.Based on REOF regionalization and dominant circulation classification,the models are eval-uated with traditional categorical scores,Fractions Skill Score(FSS),and Method for Object-Based Diagnostic Evaluation(MODE).Results show that the global model ECMWF has the highest overall TS and FSS scores and the lowest false alarm rate in northwestern Sichuan,but significantly underestimates extreme rainfall intensity.CMA-GFS performs well in intensity forecasts for plateau vortex-type events and accurately locates rainfall for plateau trough-type and plateau shear-line-type events.Among regional models,CMA-MESO has a higher hit rate,while SWC-WARR shows the best spatial pattern matching.Both perform better in the complex terrain of southwestern Sichuan for mesoscale processes such as high-pressure influence-type and dual-high shear-type events.However,they present obvious systematic biases,including overestimated rainfall areas,significant wet biases,and earlier predicted precipitation onset,leading to higher false alarm rates and lower TS scores.The diur-nal peak of FSS appears at 11:00-14:00(Beijing Time),caused by the overlap of early regional model forecasts and late global model forecasts with observed afternoon convection.Cross-section analyses indicate that wet bias-es result from overestimated mid-low-level humidity,excessive orographic lifting,displaced moisture conver-gence centers,and positional errors of key weather systems.Premature low-level convergence during the convec-tive initiation stage is the main cause of early forecast onset.For operational applications,large-scale processes should refer to ECMWF/CMA-GFS to determine rainfall ranges,while mesoscale convective centers should rely on CMA-MESO/SWC-WARR.It is recommended to shrink the rainfall areas and delay the predicted onset time of regional models by 2～4 hours to fit the observed afternoon convective characteristics over the Western Sichuan Plateau.关键词
川西高原/环流分型/降水预报检验/分数技巧评分(FSS)/基于对象的评估诊断方法(MODE)/系统性偏差Key words
Western Sichuan Plateau/circulation classification/precipitation forecast verification/Fractions Skill Score(FSS)/Method for Object-Based Diagnostic Evaluation(MODE)/systematic bias分类
天文与地球科学引用本文复制引用
武敬峰,徐晓芳,阳春芳,黄楚惠,张雷,张其圣..川西高原夏半年数值模式降水预报分区分型精细化检验评估[J].高原气象,2026,45(4):1027-1043,17.基金项目
高原与盆地暴雨旱涝灾害四川省重点实验室科技发展基金项目(省重实验室SCQXKJYJXMS202416) （省重实验室SCQXKJYJXMS202416）
四川省气象局强对流天气短临预报关键技术研究重点创新团队项目(SCQXZDCXTD202401) （SCQXZDCXTD202401）
阿坝州灾害性天气监测预报预警和服务创新团队项目(阿气发[2023]47号) （阿气发[2023]47号）
