Unveiling the Surge: Exploring Elevated Air Pollution Amidst the COVID-19 Era (2019–2020) through Spatial Dynamics and Temporal Analysis in Delhi

This comprehensive study delves into the complex issue of air pollution in Delhi, with a specific focus on the levels of PM 2.5 , PM 10 , NO 2 , and O 3 during 2019 and 2020 across all four seasons. By analyzing primary data and employing advanced GIS techniques, the research not only quantifies pollution levels before and during the COVID-19 pandemic but also identifies high-risk areas and establishes a clear link between pollution and public health. The study reveals that 2019 witnessed more severe pollution levels compared to 2020, with PM 2.5 and PM 10 consistently exceeding WHO guidelines. Notably, PM 10 levels breached Air Quality Index (AQI) standards, particularly during the winter season when it peaked at 67.99 µg/m 3 and increased post-monsoon due to crop burning. Surprisingly, summer 2019 exhibited PM 2.5 levels surpassing those of winter, underscoring the impact of reduced vehicle emissions during the summer months, while winter pollution levels remained relatively stable. The COVID-19 lockdowns in 2020 led to a substantial reduction in summer AQI by up to 58.00%, emphasizing the role of human activities in air quality. However, the study also indicates that monsoon AQI varied across different areas, with some experiencing higher emissions. Winter and post-monsoon AQI fluctuated by up to 24%, reinforcing the importance of continuous monitoring and source control measures. This research highlights the crucial role of Geographic Information Systems (GIS) in data analysis and informed decision-making for mitigating air pollution in Delhi. Its findings provide valuable insights for policymakers, offering guidance on promoting sustainability, public health, and a cleaner environment. In summary, the integration of GIS-driven pollution mapping aids in understanding and addressing the complex issue of air quality, ultimately contributing to a healthier and more environmentally friendly Delhi.