东亚及其周边海域的一年大气再分析资料试验与评估

One-year experiment and evaluation of atmospheric reanalysis in East Asia and nearby coastal zones

目前东亚及其周边海域还无公开的高分辨率区域再分析资料,但对该地区的高分辨率区域再分析的需求日益增长.该文使用天气研究与预报模式(WRF)和格点统计插值(GSI)同化系统搭建东亚区域再分析系统(EARS),并用三维变分和部分循环同化的方式研制一年再分析试验数据;进而使用气象信息综合分析处理系统(MICAPS)的站点观测资料、欧洲中期天气预报中心再分析5(ERA5)的全球再分析资料、热带降水测量任务(TRMM)的降水资料对一年试验数据进行初步评估.评估结果表明:一年再分析试验数据能较好地表征大气状况,其模拟效果接近甚至优于ERA5;在500hPa层面上,EARS与ERA5所得结果在环流分布上基本一致,但对青藏高原及印度季风区的模拟效果则有差异;在降水评估中,EARS与TRMM的降水分布和强降水中心均能较好地对应.

There is no publicly available high-resolution regional reanalysis in East Asia and its nearby coastal zones.However,the demands for high-resolution regional reanalysis in this area are increasing.Using weather research and forecasting(WRF)model and gridpoint statistical interpolation(GSI),East Asian regional reanalysis system(EARS)was set up.With three-dimensional variational data assimilation and partial cycling mode,a one-year experimental dataset was generated.By comparing with meteorology information comprehensive analysis process system(MICAPS)station observation data,European Center for Medium-rarge Weather Forecasts reanalysis 5(ERA5)global reanalysis data,and tropical rainfall measuring mission(TRMM)precipitation data,the oneyear experimental dataset was evaluated.The one-year experimental reanalysis dataset can represent the status of atmosphere well,and its simulation result is close to that of ERA5 and even better.At the 500 hPa level,the circulation patterns of EARS and ERA5 are virtually coincident,but the simulations over Tibetan Plateau and Indian monsoon area are different.In the precipitation assessment,the patterns of precipitation and the centers of heavy precipitation of EARS and TRMM are consistent.