Correlation between MODIS aerosol optical depth and air pollution index — A case study of Zhengzhou city in Henan Province, China

The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on NASA's Terra satellite provides high quality data for retrieval of aerosol optical depth (AOD). In this paper, a novel approach is proposed to retrieve AOD at 1000m resolution over Zhengzhou city. Then Correlation analysis of AOD derived from MODIS data and Air Pollution Index (API) measured at 3 monitoring sites affiliated to Zhengzhou Environmental Protection Agency (EPA) in 2009 shows the average value of the correlation coefficients from the 3 sites is only 0.2936. When AOD is amended by aerosol scaling height (ASH), it rises to 0.4142. Then the regression analysis of API with the corrected AOD, Angstrom exponent and water vapor content shows that AOD from MODIS data can be an effective token of API and distribution maps of API can be drawn using the model derived from the regression analysis.