Estimation of Ultrahigh Resolution PM2.5 Mass Concentrations Based on Mie Scattering Theory by Using Landsat8 OLI Images over Pearl River Delta

The aerosol optical depth (AOD), retrieved by satellites, has been widely used to estimate ground-level PM2.5 mass concentrations, due its advantage of large-scale spatial continuity. However, it is difficult obtain urban-scale pollution patterns from the coarse resolution retrieval results (e.g., 1 km, 3 or 10 km) at present, and little research conducted on concentration high remote sensing data. In this study, a physical model proposed based Mie scattering theory evaluate concentrations using Landsat8 Operational Land Imager (OLI) images. First, Second Simulation Satellite Signal in Solar Spectrum (6S) (which can simulate transmission process solar radiation Earth-atmosphere system calculate radiance top atmosphere) build lookup table retrieve AOD coast blue bands improved deep (DB) method. Then, Angstrom formula green red bands. Second, dry near-surface four (coast, blue, green, red) obtained through vertical correction humidity correction. Third, particles are divided into types standard atmosphere (SRA) model, properties different analyzed derive volume distribution particles. Finally, relationship between each band correlated, theory, established concentrations. obtained. show that urban scale detail. reasonable with correlation coefficient (R2) 0.66 root mean square error (RMSE) 0.1037 OLI MODO4 DB 550 nm. compared values measured ground monitoring stations. RMSEs for certain day years, including 2017, 2018, 2019, 2020, 11.9470 μg/m³, 11.9787 7.4217 5.4723 respectively. total RMSE 10.0224 μg/m³. ultrahigh provide details support better decisions atmospheric environmental governance.