Air_Quality

Air pollution is one of the vital problems for the sustainability of cities and public health. enabling to investigate the impact of human/industrial activities on the air pollution. In this study we investigated the spatio-temporal density of TROPOMI based ozone (O3), sulphur dioxide (SO2), CO products, and MODIS-derived Aerosol Optical Depth (AOD) in three different years (2019, 2020, 2023) and in three different months, January, May, November 2019, January, May and November 2020 and the same date for 2023. over Milan City (Comune)- Italy using Google Earth Engine (GEE). So, the results showed a significant decrease in CO from January 2019 (0.037 mole / m2) to January 2023(0.033 mole/ m2), and if consider monthly data, cold seasons exhibit higher concentration of CO, such as January 2020 (0.036 mole / m2), and in the summer we can see the CO decreased May 2020 (0.034 mole / m2).
SO2 didn’t decrease and had slightly higher concentrations in February 2023 (0.00066 mole / m2). compared to February 2019 (0.00064 mole / m2), and with higher concentration in February 2020 (0.0013 mole / m2), but monthly SO2 is same as CO, in the summer such as May 2023 (0.00005 mole / m2) the concentration of SO2 decreased but during the cold season increase again. Ozone (O3) as we can see on the graph level of O3 reach their peak concentration, and compared to November, it remains relatively in high level. It means that during the summer months with increasing the sunlight and warmer temperatures O3 increases too. It should be because of chemical reactions involving pollutants like nitrogen oxides and volatile organic compounds. Aerosol Optical Depth (AOD) which is a measure of how much light is absorbed or scattered by aerosol particles in the atmosphere. A higher AOD indicates more aerosol particles present in the atmosphere that have a big effect on atmospheric conditions.
Our analysis shows that during the summer months (May 2019), AOD increase to 343 PPM and decreased to 147 PPM in cold weather or in the winter (January 2019).