大气科学2026，Vol.50Issue(3)：701-716,16.DOI:10.3878/j.issn.1006-9895.2501.24107
FY-3D卫星MWHS II资料直接同化对北京7·31暴雨预报的影响
Influence of Direct Assimilation of FY-3D Satellite MWHS II Data on Rainstorm Forecast in Beijing on 31 July 2023
摘要
Abstract
In this study,the authors examine the impact of direct assimilation of FY-3D satellite MWHS II microwave humidity sounder data on extreme rainfall prediction,using the heavy rainstorm in Beijing on 31 July 2023,as a case study.Comparative experiments were conducted before and after data assimilation,and the effects across multiple scales and variables were analyzed using the WRF(Weather Research and Forecasting)numerical prediction model.The results show that MWHS II data assimilation considerably improved the extreme rainfall simulation.It successfully captured the maximum rainfall center,which exceeded 550 mm,and provided a more accurate simulation of rainfall distribution.This study also highlights the effect of assimilation on large-scale systems,thereby improving large-scale environmental fields by creating favorable conditions for extreme rainfall events.Key improvements include a strengthened temperature gradient in critical areas,optimized water vapor distribution,especially over the eastern sea,and an increased north-south pressure gradient.Together,these factors maintain a stable,large-scale background that supports precipitation.The impact on convective systems was more noticeable on a smaller scale.The vertical vorticity structure was optimized over the Beijing area,with enhanced negative vorticity in the mid-to-upper atmosphere and increased positive vorticity in lower levels,promoting upward motion.The atmosphere became more unstable,with increased relative humidity in the lower levels,decreased humidity in the mid-levels,and a steeper vertical temperature gradient.These factors contribute to strong convection triggering and maintenance.In addition,the microphysical processes improved.More snow and graupel particles formed in the mid-to-upper layers,and the conversion of cloud water to rainwater accelerated in lower levels,enhancing the overall precipitation efficiency.These effects were most prominent during the first 36 h of the simulation,emphasizing the critical role of data assimilation during the early and developing stages of precipitation.关键词
卫星资料同化/微波湿度计/FY-3D卫星/多尺度系统Key words
Satellite data assimilation/Microwave hygrometer/FY-3D satellite/Multiscale system分类
天文与地球科学引用本文复制引用
徐忠燕,杜涵,徐瑾,李玉鹏,田少龙,平凡..FY-3D卫星MWHS II资料直接同化对北京7·31暴雨预报的影响[J].大气科学,2026,50(3):701-716,16.基金项目
国家重点研发计划项目2023YFC3007700,浙江省"尖兵领雁+X"研发攻关计划项目2025C02028 National Key Research and Development Program(Grant 2023YFC3007700),Zhejiang Province"JianBingLingYan+X"Research and Development Plan of China(Grant 2025C02028) （Grant 2023YFC3007700）
