In a seasonal shift, Delhi has recorded its slowest deterioration in air quality in seven years during the transition from September to October, while Mumbai has witnessed pollution levels more than double over the same period. A Moneycontrol analysis of air quality data from 11 major Indian cities found that Delhi’s average AQI rose 48.5%, compared with Mumbai’s 105.1% increase.
The analysis compared average AQI readings for September 16-30 and October 1-25 for each year from 2020 to 2026. Delhi’s increase was lower than its six-year average of 75.8%, while Mumbai’s rise exceeded its corresponding average of 76.2%. Bengaluru and Kolkata also recorded sharper increases than their respective six-year averages.
