Remote Sensing of High Spatial Resolution Aerosol Optical Depth with MODIS Data over Hong Kong

Abstract

Based on the operational arithmetic of remote sensing aerosol optical depth (AOD) with the Moderate Resolution Imaging Spectroradiometer (MODIS) published by National Aeronautics and Space Administration (NASA) of the United States, an AOD retrieval method with 1 km resolution MODIS data is developed, and it is used for obtaining the AOD over Hong Kong. Comparing these products with long\|term sunphotometer observations it is found that the relative error of the products is about 20%, which indicates that this method applied in Hong Kong has quite enough precision to capture the urban aerosol distribution. Then an air pollution case is presented, and the high\|resolution AOD distributions and absolute values are compared with the 10 km resolution level 2 products from NASA and mass concentration of PM10 (particulate matter with the diameter less than 10 μm) observed at 14 stations in Hong Kong. The results show that the satellite products can be used for describing the urban\|scale aerosol distribution and can provide lots of new information on better understanding atmospheric environment pollution.