Monitoring of the Nitrogen Dioxide Concentration in the Period of Covid-19 Using Sentinel-5 Satellite Data (Case Study: Shiraz Metropolis)

Nitrogen dioxide is considered one of the important indicators for evaluating the air quality of cities, therefore, identifying the areas contaminated with this pollutant is very important. One of the sciences and technologies that can help urban environmental experts to identify these areas in the shortest time and at a lower cost is satellite remote sensing. Currently, satellite remote sensing is a useful technology for measuring atmospheric pollutants at the global, regional, and urban levels. Therefore, the present research has identified and investigated the temporal-spatial distribution of nitrogen dioxide gas during the spread of Covid-19 using Sentinel-5P satellite data in the Shiraz metropolis for 24 months (2019 and 2020). Based on the results of this research, the highest monthly average values of nitrogen dioxide gas in 2019 and 2020 are related to the autumn season. In addition, district 2 of Shiraz was identified as the most polluted area in the two years studied. In addition, after analyzing the parameters of wind, precipitation, and temperature, it was found that the wind factor with a correlation coefficient of -0.638 at a significance level of 1% compared to other climate factors had the greatest impact on the change in nitrogen dioxide gas values. The Covid-19 crisis also played a role in changing the amount of nitrogen dioxide gas in 2020 compared to 2019 every month with its impact on the reduction of traffic and urban traffic. The pattern of changes in the average nitrogen dioxide gas related to satellite data in the studied years had a decreasing trend, which was consistent with the pattern of changes in the values obtained from the pollution monitoring station. The results of this research can be useful in urban livability and crisis management.