An Investigation of Air Pollution in Hong Kong with ASTER Data

This paper describes an approach to assess air quality over urban area using high spatial resolution remote sensing data. As an example, we report here the results of the air quality assessment in Hong Kong area on April 17, 2006. An aerosol optical thickness (AOT) retrieval method with 15 m resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data was developed by integration of urban BRDF model and ASTER dual-angle view capabilities in 3N and 3B bands, which was used for calculation the AOT values over Hong Kong. Ground-level PM2.5 values in Hong Kong area was obtained from a linear regression equation describing the relationship between AOT and PM2.5. Results showed that the detailed information of air quality in Hong Kong area could be obtained from the high-resolution retrieval results and indicated that satellite remote sensing of aerosol could serve as an efficient tool for monitoring the spatial distribution of particulate pollutants on the ground-level. Further validation with in situ land surface AOT and pollution concentration data should be carried out in the future.