Jamrud Aminuddin, R. Farzand Abdullatif, Sunardi, Mashuri, Laras Toersilowati, Albertus Sulaiman, Pakhrur Razi, Hitoshi Irie, Hiroaki Kuze
Atmospheric aerosol is indispensable in the study of Earth’s radiation budget. One of the indispensable parameters is aerosol optical thickness (AOT). A new monitoring technique to obtain the AOT has been developed by concurrent observation of the sunphotometer and Himawari-8 satellite from surface and space looking, respectively. The method is implemented in Chiba city, southeast of Tokyo metropolitan, the capital city of Japan. The solar radiation at the top of the atmosphere is calculated using the Langley extrapolation method in the AOT calculation utilizing sunphotometer data by linearizing Beer’s Law equation. For most clear sky situations, sunphotometer data is used to retrieve solar radiation at the top of the atmosphere for the calibration’s Langley plot analysis. The ozone gasses (O3) contribution from the GOME-2 satellite and the carbon dioxide (CO2) molecule from a nearby station are the correction factors used in determining AOT. On the other hand, the AOT estimation procedure using the Himawari-8 satellite is computed employing apparent reflectance, air mass, and surface reflectance. The apparent reflectance is estimated using imagery data of the Himawari-8 satellite. The air mass is calculated based on the solar zenith angle. The surface reflectance is derived from radiative transferee calculation using 6S (Second Simulation of a Satellite Signal in the Solar Spectrum). The essential input parameters of the 6S code are the AOT of the sunphotometer, surface reflectance of Himawari-8, solar zenith angle, and solar azimuth angle. The AOT estimation in this study using both the sunphotometer and Himawari-8 satellite shows a slight deviation value of approximately 10%. The present approach will be generally valuable in estimating the AOT based on ground-based instruments and satellite sensors. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
Department of Physics, Universitas Jenderal Soedirman, Purwokerto, 53122, Indonesia; Department of Mathematics, Universitas Jenderal Soedirman, Purwokerto, 53122, Indonesia; Center for Atmospheric and Climate Research, National Research and Innovation Agency, Jakarta, 10340, Indonesia; Research Centre of Disaster Monitoring and Earth Observation, Universitas Negeri Padang, Padang, 25131, Indonesia; Center for Environmental Remote Sensing, Chiba University, Chiba, 2638522, Japan
