Assessing air quality extremes: a comparative extreme value analysis of metropolitan cities across India and the world.

Air pollution is a significant global issue that impacts public health, particularly in urban areas where pollution levels often exceed safe limits. The Air Quality Index (AQI) serves as a key metric to assess the concentration of harmful pollutants such as particulate matter (PM), ozone, and nitrogen oxides. This study conducts an extreme value analysis (EVA) of AQI data from five major Indian cities-Delhi, Mumbai, Kolkata, Chennai, and Hyderabad-and eight other metropolitan cities worldwide, including Dhaka, Chengdu, and Bogota. The goal is to evaluate the probability of extreme pollution events and compare the seasonal patterns of air quality in these cities. Our findings indicate that cities like New Delhi and Dhaka consistently experience AQI levels that exceed hazardous thresholds, particularly during the winter months and festival seasons. This study provides critical insights into the air quality crisis in India and other regions, emphasizing the need for targeted policy interventions, including stricter emission regulations, adoption of cleaner energy sources, and enhanced public awareness campaigns to mitigate the effects of extreme pollution events.