Retrieval Aerosols Optical Thickness Over Beijing And Its Surrounding Area From MODIS Data

Aerosols affect the climatic change and air pollution significantly. Retrieval aerosols optical thickness over Beijing and its surrounding area from MODIS data aims at providing a new, economical and convenient measurement for urban air pollution monitoring.Based on the 6S radiative transfer code, the dense dark vegetation method and contrast reduction method of estimating the optical thickness over land surface from EOS-Terra/MODIS data at wavelengths of 0.66μm and 0.47μm were used to retrieve the aerosols optical thickness over Beijing and its surrounding area. The aerosols optical thickness estimated from the ground-based sun photometer at the same time as the pass of the satellite were used to validate the retrieval from satellite data. There were four kinds of aerosol model applied to remote sensing of aerosol optical thickness. And, the paper has given the way to select the best combination of method, satellite channel and aerosol model which could obtain the reasonable aerosols optical thickness. The study result showed that aerosols optical thickness over study area obtained from MODIS data could be used to air pollution monitoring.Moreover, we obtained the aerosols optical thickness distribution in Spring Festival of 2003, and analyzed air pollution with these results. We found that the human production and living behaviour strongly affected the air environment quality.