TROPOMI NO2 and SO2 Temporal Changes over Large Point Sources and Their Relationship with Electricity Production

This study focuses on the spatial distribution and temporal changes of NO2 and SO2 pollution over large point sources using high-resolution TROPOMI retrievals, and aims to find a correlation between the retrievals and electricity production. SO2 retrievals showed highest signals over power plants, whereas NO2 retrievals showed highest signals over large cities. Daily and monthly time series of NO2 and SO2 for the selected nine coal power plants were compared with electricity production for two years. Correlations between NO2, SO2, and electricity production were calculated for daily and monthly averages for every power plant. Then, the monthly averages with more than 23 days data (~75%, May-October) were used for correlation analysis. Highest correlations were observed for lignite-fired Afsin Elbistan Power Plant with highest total capacity in Turkey. The monthly correlations for May-October were found as 0.71 for NO2, 0.84 for SO2 for Afsin Elbistan Power Plant, as 0.45 for NO2 and 0.43 for SO2 for all selected power plants. Temporal changes in electricity production can be captured on monthly-basis, however, the correlations were lower on daily-basis. Point sources located close to land-sea boundaries and multiple sources located in the same region were poorly captured using satellite retrievals.