The growing concern over Delhi's air quality has triggered questions regarding the condition of the air in other big cities of India. A recent survey by the organisation Climate Trends reports that the air in most big cities remains far from "safe," and Kolkata is no exception. However, according to the study, Kolkata fares better than Delhi or Lucknow.
The AQI in Kolkata stays within the "moderate" range throughout most of the year, though the levels of pollution rise slightly during winter, particularly in pockets of South Kolkata and the riverfront areas. The findings are based on an analysis of trends from Central Pollution Control Board data from 2015-2025.
Also Read | Delhi AQI hits 341; city spends over 15 days in ‘very poor’ air quality
Kolkata's AQI stays 'moderate' through the year
Kolkata is found to be less polluted compared to Delhi or Lucknow. The study finds that the city's AQI normally oscillates between 80 and 140, hence falling under the "moderate" category.
The report also highlighted the fact that, since 2022, Kolkata's air quality has gradually improved. However, during the winter months, AQI often slides into the "poor" category. During this season, areas such as Ballygunge, Jadavpur, and neighbourhoods along the river record a sharper rise in pollution.
Why Kolkata’s pollution spikes?
During winter, dust, heavy traffic, along industrial emissions from such areas as Topsia–Tangra and Howrah exacerbate this situation. Although recent steps, like cleaner fuel, better emission control, and increased use of electric vehicles, have gained some benefits, the dust raised during construction during winter and stagnant air push the AQI to unhealthy levels.
Although Kolkata's AQI remains between 80 and 140 throughout the year, winters are witnessing a rise in dust, vehicular congestion, and industrial emissions. Adoption of cleaner fuel and increasing EV usage have brought some relief, but low wind movement and construction activity are continuously raising pollution levels.
Delhi tops list as pollution capital
According to the Climate Trends study, Delhi has remained the most polluted city in the country over the last decade. In 2016, its AQI had crossed 250, and even in 2025, it hovers around 180.
Similar levels of pollution are reported from Lucknow, Varanasi, and Ahmedabad. While these states have shown a gradual decline in pollution after 2019, none of them has been able to bring the AQI to a safe range.
Also Read | Postal Court 134th Session: Submission open till December 3; Here is how to file complaints
According to experts, winter pollution across the Indo-Gangetic plains is not because of a single cause, such as vehicles or factories. Weather plays a big role. Cold northern winds, low rainfall, and dense population make conditions favourable for particulate matter to get trapped close to the ground, not allowing dispersion.
Policy and technology-driven solutions are needed. Weather expert Mahesh Palawat explains that with falling temperatures, the formation of an inversion layer barrier, hindering the air and sunlight from clearing pollutants-increases. According to Palak Balian of Climate Trends, India needs long-term, science-based policy decisions that are 'firm' towards air pollution. If not, people residing in any Indian metropolis will be seen struggling for cleaner air.
