Comparative Analysis of Aqi on Diwali Festival in Metropolitan and Nonmetropolitan Cities

-Air pollution remains a critical environmental and public health challenge in Indian cities, with Delhi experiencing some of the worst air quality levels globally. Among various contributing factors, Diwali festivities—characterized by widespread firecracker usage—lead to a significant deterioration in air quality. Additionally, the annual practice of stubble burning in the neighboring states of Punjab and Haryana further exacerbates pollution levels, particularly in the postDiwali period. This study aims to comprehensively assess the impact of Diwali-related emissions on air quality by comparing AQI levels in metropolitan cities (Delhi and Jaipur) and non-metropolitan cities (Chittorgarh and Sirohi) before and after the festival. Air quality data for the period from October 21 to November 10, 2024, was collected from the Central Pollution Control Board (CPCB). The study examines AQI fluctuations, identifies key pollutants responsible for air quality degradation, and evaluates the role of meteorological factors such as wind speed, temperature, and atmospheric stability in pollution dispersion. Findings reveal a stark contrast between metropolitan and non-metropolitan cities in terms of air quality deterioration. Prior to Diwali (October 20–30), Delhi recorded an average AQI of 376.08 (Very Poor), while Jaipur stood at 184.71 (Moderate to Poor). In contrast, non-metropolitan cities such as Chittorgarh (119.78 AQI) and Sirohi (89.65 AQI) maintained relatively better air quality. However, post-Diwali (October 31–November 9), AQI levels in metropolitan cities surged dramatically, with Delhi peaking at a hazardous 412.22 AQI (Severe) and Jaipur at 290.90 AQI (Poor). The sharp rise in pollution levels is attributed to firecracker emissions, increased vehicular and industrial activity, and unfavorable meteorological conditions leading to pollutant accumulation. In nonmetropolitan cities, the increase in AQI was less pronounced, with Chittorgarh reaching 156.60 AQI (Moderate to Poor) and Sirohi slightly increasing to 99.93 AQI (Satisfactory to Moderate). The comparatively lower pollution levels in non-metropolitan areas highlight the significant impact of urbanization, population density, and anthropogenic activities in worsening air quality. Additionally, the study observes the formation of haze and smog in Delhi, exacerbated by high levels of PM2.5 and PM10, sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and other suspended particulate matter emitted during Diwali celebrations. The findings of this study emphasize the urgent need for stringent regulatory measures, effective implementation of firecracker bans, and public awareness campaigns promoting eco-friendly alternatives. Additionally, longterm policy interventions, including restrictions on stubble burning, enhanced vehicular emission controls, and sustainable urban planning, are essential to curb air pollution. Future research could focus on multi-year AQI trends, health impacts of pollution spikes, and the efficacy of government policies in mitigating seasonal air quality deterioration. By fostering collective action from policymakers, environmental agencies, and citizens, it is possible to mitigate the adverse environmental and health effects of air pollution during Diwali and beyond.