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An algorithm for aerosol effective height (AEH) was developed for operational use with observations from the Geostationary Environment Monitoring Spectrometer (GEMS). The retrieval technique uses the slant column density of the oxygen dimer (O2-O2) at 477 nm, which is converted into AEH after retrieval of aerosol and surface optical properties from GEMS operational algorithms. The AEH retrieval results show significant AEH values and continuously monitor aerosol vertical height information in severe dust plumes over East Asia, and the collection of plume height information for anthropogenic aerosol pollutants over India. Compared to the AEH retrieved from Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), the retrieval results show insignificant bias with a standard deviation of 1.4 km for the AEH difference over the GEMS observation domain from January to June 2021 due to uncertainty in input parameters for aerosol and surface. The AEH difference depends on aerosol optical properties and surface albedo. Compared to the aerosol layer height obtained from the tropospheric monitoring instrument (TROPOMI), differences of 0.78 ± 0.81 and 1.16 ± 0.92 km were obtained for pixels with single scattering albedo (SSA) < 0.90 and 0.90 < SSA < 0.95, respectively, with significant dependence on aerosol type.

[ABSTRACT]Integrated approach has been adopted at the ADvanced Environmental Research Center (ADEMRC), Gwangju Institute of Science and Technology (GIST), Korea for effective monitoring of atmospheric environment. Various active and passive optical remote sensing techniques such as multi-wavelength (3β + 2α) Raman LIDAR, sun-photometry, MAX-DOAS, and satellite monitoring have been utilized. This integrated monitoring system approach combined with in-situ surface measurement is to allow better characterization of physical and optical properties of atmospheric aerosol. Atmospheric environmental change monitoring has been conducted by measuring trace gases and aerosol in urban areas including Seoul, Gwangju, and Beijing as well as in remote areas such as volcanic sites and coastal areas.

Total Vertical Column Density (VCD) of NO₂, a key component in air quality and tropospheric chemistry was measured using a ground-based instrument, Pandora, in Seoul from March 2012 to October 2013. The NO₂ measurements using Pandora were compared with those obtained by satellite remote sensing from Ozone Monitoring Instrument (OMI) where the intercomparison characteristics were analyzed as a function of measurement geometry, cloud amount and aerosol loading. The negative biases of the OMI NO₂ VCD were larger when cloud amount and Aerosol Optical Depth (AOD) were higher. The correlation coefficient between NO₂ VCDs from Pandora and OMI was 0.53 for the entire measurement period, whereas the correlation coefficient between the two was 0.74 when the cloud amount and AOD were low (cloud amount