9:15 AM - 9:30 AM
[ACG36-14] Development of all-sky assimilation of 183 GHz microwave radiance data in the JMA global NWP system
The major information of the microwave imager observation comes from microwave emissions of atmospheric water vapor, clouds and precipitation. However, in high frequency range of the microwave spectrum, scattering effects of microwave radiation with clouds and precipitation particles play a dominant role in the observed radiances. Therefore, the performance of microwave radiative transfer model (RTM) used in the data assimilation and the representation of cloud ice and/or solid precipitation in the input atmospheric profiles for RTM affect the quality of analysis and forecast in the NWP system.
In this study, various microwave humidity sounding radiances observed at microwave 183.31 GHz water vapor absorption line are used (e.g. MHS, GMI, SAPHIR, SSMIS, ATMS, MWHS-1, MWHS-2) to reveal insufficient representation of the input atmospheric profiles or performance of RTM. As RTM, RTTOV-SCATT is used. Results of the comparison of the observation and the simulation showed the forecast model’s deficiency of cloud ice and/or solid precipitation representation under convective cloud conditions. The detail results are presented in the conference.