Investigation of Air Pollution in Tehran According Wind And Precipitation Conditions

To investigate the role of wind and precipitation on air pollution in the metropolis of Tehran, daily NO2 data from the Sentinel satellite and daily wind and precipitation data from Mehrabad station from August 1, 2018, to December 31, 2021, were used. To examine the relationship between precipitation and wind data with air pollution, the correlation method and the existence of significant differences in air pollution in different conditions, t-test was used. The results showed the variance and mean NO2 of rainy days and days without rainfall were not equal and on rainy days the amount of air pollution was reduced by 31.06%. The average air pollution on rainy days is less than on days without rainfall, but no specific pattern was observed between the amount of rainfall and the reduction of air pollution. The results showed that increasing the wind speed to 2.5 m / s will reduce air pollution, but higher speeds will not necessarily reduce pollution further. The variance and mean NO2 are not equal on windy days of more than 2.5 meters per second. At speeds of more than 2.5 meters per second, the amount of air pollution is reduced by 59.25% with 99% confidence. The results show that the effect of wind in reducing air pollution in Tehran is more than rainfall and shows a more distinct pattern of air pollution.