RETRIEVAL OF AEROSOL EFFECTIVE HEIGHT USING O₄ ABSORPTION PROPERTY FROM GEOSTATIONARY ENVIRONMENT MONITORING SPECTROMETER (GEMS) MEASUREMENTS

This study introduces an aerosol effective height (AEH) retrieval algorithm using O-4 absorption properties at 477 nm measured by Geostationary Environment Monitoring Spectrometer (GEMS). GEMS, launched in February 2020 on GeoKOMPSAT-2B, monitors air quality across Asia, including O-3, NO2, SO2, HCHO, and aerosols. The algorithm employs differential optical absorption spectroscopy (DOAS) to retrieve O-4 slant column density (SCD) and calculates the O-4 air mass factor (AMF) by dividing SCD by O-4 vertical column density (VCD), considering variations due to atmospheric temperature and pressure. AEHs were retrieved from GEMS hyperspectral radiance data during the Asian dust period in 2021. In addition, lidar measurements were used to validate the algorithm.