Improved Hourly Estimates of Aerosol Optical Thickness Using Spatiotemporal Variability Derived From Himawari-8 Geostationary Satellite

We developed a scheme to improve hourly estimates of aerosol optical thickness (AOT) from the Advanced Himawari Imager (AHI) onboard Himawari-8, the Japan Meteorological Agency's latest geostationary satellite. Taking advantage of the sampling characteristics of the AHI (10-min temporal and sub-kilometer spatial resolution), we quantify temporal and spatial variability of AOT from the observations (AOT(original)) and utilize this information to develop an hourly algorithm that produces two sets of derived AOTs: AOT(pure), derived by the application of strict cloud screening to AOT(original), and AOT(merged), derived from spatial and temporal interpolations of AOT(pure). The AOTs thus obtained from the hourly algorithm were validated against measurements from the aerosol robotic network. The root-mean-square errors (RMSEs) of the AOT(pure) and AOT(merged) products were 0.14 and 0.11, respectively, providing improvement over an RMSE of 0.20 for AOT(original).