The First Results of Cloud Retrieval from Geostationary Environmental Monitoring Spectrometer

Abstract. This research introduces the cloud retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS), the first geostationary orbit satellite, and shows the validation of its cloud products through comparison with other satellites: OMI, TROPOMI, AMI, and CALIOP. The purpose of GEMS cloud products is to correct the impact of clouds on atmospheric components retrieval, which use the O2-O2 absorption band to retrieve the effective cloud fraction (ECF) and cloud centroid pressure (CCP). The GEMS cloud retrieval algorithm showed similar cloud retrieval performance to OMI. We analyzed the cloud retrieval characteristics for cases of air pollution, typhoons, and fog in the East Asia region to evaluate whether GEMS cloud products can represent various cloud features. The present cloud validation results would initiate to improve the GEMS cloud retrieval algorithm in the future.