CMA-BJ 2.0版逐时快速更新追赶循环同化预报系统研发及应用Ⅰ:资料同化及系统构建  

On the CMA-BJ v2.0 hourly rapid update catch-up cycling assimilation and forecast system.PartⅠ:Data assimilation and system attributes

作　　者：陈敏 仲跻芹[1,2] 卢冰 童文雪[1,2] 冯琎 张舒婷[1,2] 黄向宇 范水勇 CHEN Min;ZHONG Jiqin;LU Bing;TONG Wenxue;FENG Jin;ZHANG Shuting;HUANG Xiangyu;FAN Shuiyong(Institute of Urban Meteorology,CMA,Beijing 100089,China;Key Laboratory of Urban Meteorology,China Meteorological Administration,Beijing 100089,China)

机构地区：[1]北京城市气象研究院,北京100089 [2]中国气象局城市气象重点开放实验室,北京100089

出　　处：《气象学报》2023年第6期911-925,共15页Acta Meteorologica Sinica

基　　金：国家重点研发计划课题(2022YFC3004003、2018YFC1506804);中国气象局重点创新团队(CMA2022ZD09)。

摘　　要：介绍了CMA-BJ 2.0版区域逐时快速更新循环同化分析及短时预报业务系统在逐时更新循环和资料同化方面的关键技术特点。该系统采用分析增量更新作为初始化方案,有效抑制了初始噪声累积问题;通过充分考虑各类观测资料实际到报截断时长的差异,发展了包括循环分析和更新预报两个部分耦合的逐时追赶循环运行框架,实现了对各类观测资料充分高效的利用,也较好地兼顾了短临预报服务对逐时更新循环预报产品的时效性要求;通过在分析循环的同化背景场部分应用动态混合方案,实现了全球模式大尺度场对区域模式中小尺度热动力场发展的动态约束,有效抑制了快速更新循环预报误差累积导致的大尺度预报场变形的问题;在资料同化方面,实现了中国全国雷达反射率因子拼图资料的同化应用,并通过仅在更新预报部分开展雷达反射率资料同化以规避连续循环同化造成的水汽正向过量累积、调整雷达同化时的背景场误差的方差和长度尺度两方面的策略优化有效提升了雷达同化的应用效果;此外,在CMA-BJ 2.0版系统中实现了中国全国风廓线雷达观测资料的实时同化应用。In this paper,the key technical features of CMA-BJ v2.0,the Hourly Rapid Catch-up Cycling Assimilation and Forecast System,are introduced in detail.This system uses IAU(Incremental Analysis Update)as the initialization scheme,which effectively suppresses the initial noise accumulation problem.By fully considering the actual truncated time of all kinds of observations'arrival,the two coupling parts,e.g.,the cycle analysis and forecast update implementing data with different cut-off times,run in turn within each hourly cycling to meet the high demands of nowcasting and short-term forecast services.By applying the dynamic forecast hybrid scheme to the assimilated background field,the dynamic constraint of large-scale fields from global models on the development of micro-and meso-scale thermal and dynamic fields in the regional model is realized,and the deformation of large�scale prediction fields caused by the accumulation of rapid update cycle prediction errors is effectively suppressed.In terms of data assimilation,the national-wide mosaic radar reflectivity is only assimilated at the stage of forecast update to avoid continuous accumulation of water vapor.The radar assimilation background field error variance and length scale strategy optimization effectively promote the application of radar assimilation effect.In addition,real-time assimilation of national wind profile radar observations is realized in the CMA-BJ v2.0 system.

关 键 词：快速更新循环 初始化 雷达资料同化 风廓线同化 分析增量更新 

分 类 号：P456.7[天文地球—大气科学及气象学]