摘要
集合预报在数值天气预报体系中具有重要地位,因此如何有效提取集合样本信息以提高集合预报技巧一直是一个重要课题。基于中国全球集合预报业务系统(GRAPES-GEPS)的500 hPa高度场集合资料开展对环流集合预报的分类释用方法研究,并对集合聚类预报结果进行了检验分析。通过在传统Ward聚类法中引入动态聚类的“手肘法”方案,发展了环流集合预报分类释用方法。针对该方法的个例分析表明,对于中国中东部地区环流集合预报的聚类释用方法能够有效地划分出最有可能发生的环流形势类型并提供发生概率。确定性预报综合检验结果显示,集合预报聚类结果中发生概率最高的集合大类相对于集合平均的预报技巧有明显提升,并随着预报时效的延长提升更明显。总体来看,通过集合预报的分类释用方法划分环流形势类型可以为天气预报提供参考依据,具有实际应用价值。
Ensemble prediction is playing a vital role in the development of numerical weather prediction system.Hence,how to effectively extract the information of ensemble swatches to improve ensemble forecasting skills has always been an important issue.Based on the 500 hPa geopotential height data from the China global ensemble forecasting operational system(GRAPES-GEPS),the ensemble forecasts have been classified by a cluster analysis approach,and the cluster results are further verified.By introducing the dynamic"elbow"cluster scheme,a classification interpretation method for circulation ensemble forecast is developed,and the related deterministic forecast verification is conducted using the GRAPES-GEPS real-time ensemble forecast dataset.A case study using this method indicates that the clustering of ensemble forecasts of 500 hPa circulation field over central and eastern China can efficiently classify the circulation types and meanwhile provide corresponding probabilities of their occurrence.The deterministic forecast verification results show that with the forecast lead time increase,the primary clusters of ensemble forecasts have significantly improved prediction skill scores together with the highest probability compared to those of the ensemble mean.Generally speaking,the classification interpretation method for circulation ensemble forecasting can provide a quite helpful reference for weather forecast,and it is of great value for potential application to operational weather forecast.
作者
罗月琳
高丽
陈权亮
蔡宏珂
任宏利
LUO Yuelin;GAO Li;CHEN Quanliang;CAI Hongke;REN Hongli(College of Atmospheric Science,Chengdu University of Information Technology,Chengdu 610225,China;CMA Numerical Prediction Center,National Meteorological Center,Beijing 100081,China;Laboratory for Climate Studies,National Climate Center,Beijing 100081,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China)
出处
《气象学报》
CAS
CSCD
北大核心
2021年第4期646-658,共13页
Acta Meteorologica Sinica
基金
国家重点研发计划项目“冬奥中短期精细数值天气预报技术应用研发”(2018YFF0300103)
国家自然科学基金项目(41875138、42075087、U20A2097)
气象预报业务关键技术发展专项(YBGJXM2020)。
关键词
集合预报
分类释用
Ward聚类
环流
检验分析
Ensemble prediction
Classification interpretation method
Ward analysis
Circulation
Verification
