All-Sky Microwave Radiance Assimilation in the Korean Integrated Model Forecast System

An all-sky microwave radiance assimilation system has been developed for the Korean Integrated Model (KIM) forecast system. This study provides an overview of the development of the Microwave Humidity Sounder (MHS) and Advanced Technology Microwave Sounder (ATMS). Although cloud and precipitation are not directly assimilated in our hybrid four-dimensional ensemble-variational assimilation system (Hybrid-4DEnVar), it was confirmed that the accuracy of the initial conditions of humidity, temperature and geopotential height was improved through all-sky radiance assimilation in the KIM. In the heavy rainfall case over Korea, all-sky radiance assimilation of MHS and ATMS has alleviated the water vapor shortage and influenced the improvement of precipitation prediction.