Air Pollution and Transportation: Evaluating Different Factors from a COVID-19 Outbreak Perspective

This paper examines how the COVID-19 outbreak affected air pollution. People around the world experienced severe changes in daily activities due to COVID-19 being an infectious disease. From the perspective of the COVID-19 outbreak, variables in this study are classified into static (spatial) and dynamic (temporal). Variables that remain constant both before and after a pandemic are called static variables. Variables with daily variations are considered dynamic variables. A three-step methodology is followed. In the first step, a descriptive analysis is performed to compare the air quality between the two periods. In the second step, data envelopment analysis is used to assess each district’s air quality efficiency based on spatial variables. A structural equation model is used in the third phase to determine how temporal factors have impacted air quality before and during the pandemic. Recognized as one of the most polluted cities globally, Tehran, Iran, is used as a case study. The results indicate that city administrations should avoid relying on weather conditions to promote air quality. The analysis suggests that distributing shopping centers and residential units throughout the city is the most effective strategy to improve air quality. Furthermore, planners and policymakers must focus on promoting green space, public and green transport, and at the same time limiting private car travel. COVID-19 demonstrated the possibility of reducing trips, but it damaged sustainable travel behavior because people shifted to private cars.