*Hiroyuki Shimizu1, Masahiro Kazumori1, Hidehiko Murata1
(1.Japan Meteorological Agency)
Keywords:Microwave, Data assimilation
Microwave radiance data from space-based observation contain a variety of information on geophysical parameters relating to the atmosphere and the earth's surface (e.g., atmospheric temperature and water vapor profiles, cloud, precipitation, surface wind and surface temperature). In this context, microwave radiance over ocean areas in clear-sky conditions has been assimilated in JMA's global numerical weather prediction (NWP) system. By properly considering microwave radiance data relating to cloud and precipitation, assimilation of all-sky (including clear-sky, cloud and precipitation) microwave radiance contributes to better forecasting of atmospheric phenomena associated with severe weather conditions. JMA developed an all-sky microwave radiance assimilation scheme for microwave imagers and microwave humidity sounders. It was introduced into JMA's operational global NWP system in December 2019. Currently, the all-sky assimilation scheme is applied to several microwave humidity sounders (GMI/GPM, MHS/NOAA-19, Metop-A, -B) and microwave imagers (AMSR2/GCOM-W, GMI/GPM, SSMIS/DMSP F-17, F-18, WindSat/Coriolis, MWRI/FY-3C).
To apply the all-sky microwave assimilation scheme to the other microwave humidity sounders (e.g., ATMS/Suomi-NPP, NOAA-20, SSMIS/DMSP F-17, F18, SAPHIR/Megha-Tropiques, MWHS-2/FY-3C), several evaluations of the data quality and data assimilation experiments were carried out. The results showed better fit of first guess to radiosonde observations and clear-sky infrared radiance observations. The details of the experiment results are presented in the conference.