Performance of Advanced Radiative Transfer Modeling System (ARMS) in Support of Satellite Data Assimilation in CMA-GFS Model

The Advanced Radiative transfer Modeling System (ARMS) is a fast radiative transfer model for satellite radiance calculations and is also used for the direct assimilation of radiances for numerical weather prediction models (NWP). ARMS can support most visible, infrared, and microwave instruments onboard both polar-orbiting and geostationary orbiting satellites from the US, Europe, and China. Both ARMS and RTTOV are employed as satellite observation operators in the China Meteorological Administration Global Forecasting System (CMA-GFS). To evaluate the performance between ARMS and RTTOV in CMA-GFS V4.0, three groups of data assimilation experiments from August 15, 2021, to August 31, 2022, were conducted. It’s shown that good agreement exists in the simulation bias of satellite radiance from both ARMS and RTTOV. Moreover, from the performance of the analysis field and forecast field, the use of ARMS as the satellite observation operator in the CMA-GFS model achieved better results than RTTOV.