Evaluation of sulfur dioxide emissions in thermal power plant and its effect on air quality in the neighboring city using Sentinel-5 images (case study: Iran, Arak)

Sulfur dioxide (SO2) is one of the most important pollutants in Arak city, and its main source is the Shazand thermal power plant (TPP) which is located along with the dominant southwest wind. This study aims to determine the role of Shazand TPP in the air pollution of Arak. A rational quadratic function is proposed to develop the relationship between SO2 emitted from Shazand TPP and pollutant concentration in Arak city using Sentinel-5 satellite images over three years. Ground stations for air quality monitoring have also been applied to assess the accuracy of Sentinel-5 satellite observations. The proposed equation was fitted to the Sentinel-5 observations with a precision of 0.15 (relative error). The cross-correlation coefficient between the observations of ground stations for air quality monitoring and Sentinel-5 images is 77%, indicating the reliability of Sentinel-5 satellite data. Experiments demonstrate that the SO2 density of Shazand TPP can effectively influence the concentration of such pollutant up to 62% in our study area.