Analysis and Validation of the Aerosol Optical Depth of MODIS Products in Gansu Province, Northwest China

The accurate determination of aerosol optical depth (AOD) is great importance for climate change research and environmental monitoring. To understand the applicability MODIS product inversion algorithm in Gansu Province, this work uses ground-based solar photometer AOD observation data to validate C6 version product. Additionally, retrieval accuracy Deep Blue (DB) products Dark Target Fusion (DB–DT combined) Province when setting different spatial sampling windows compared analyzed. Meanwhile, monitoring effects these two algorithms typical polluted atmospheric conditions are compared. results show that (1) correlation between decreases with an increasing window size. When set at 30 km × km, it more representative value thus reflecting local characteristics. (2) effect DB better than DB–DT combined on underlying surfaces. (3) seasonal variability less algorithm, has advantages spring, autumn winter, while outperforms only winter. influenced by setting. (4) Both can monitor distribution central western regions Gansu, especially high values under conditions, which represents a good effect. However, perform poorly southeast region there discontinuous northwest Gansu. Overall, higher Province. This provides reference air pollution prediction.