Retrieval of atmospheric variables using geostationary satellite image over East Asia

Abstract

Aerosol optical thickness (AOT) and water vapor (WV) was retrieved using Geo-KOMSAT2A satellite (GK-2A, Geostationary Satellite) launched in 2018, and operated by the Meteorological Satellite Center in Korea. GK-2A is equipped with 16 bands, including 4 visible bands, and is taking pictures of the East Asia region every 2 minutes. We utilized visible, near infrared, and shortwave infrared bands on AOT and WV retrieval. These bands are simultaneously affected by atmospheric scattering and surface reflection, so the contribution of each element can be simulated using the atmospheric radiation transfer model (RTM model). The first is to generate Look-up Table using RTM model of SBDART (Santa Barbara DISORT Atmospheric Radiative Transfer), the second is the atmospheric correction reflectivity calculation process. The third, WV and AOT was retrieved, and the results were compared and verified with ground measurement data. Finally, atmospheric correction was experimentally performed for polar orbit satellite (KOMSAT 3, 3A) images using WV and AOT as input variables.