Kolkata’s PM 2.5 drops in December 2024, 21.5% decline over the past 5 years

Kolkata’s air quality in December 2024 showed significant improvement, with the particulate matter (PM 2.5) concentration dropping to 44.8 micrograms per cubic meter (µg/m³). This represents a 21.5% reduction from 2019, when the PM 2.5 level was higher. The city has seen a gradual decline in air pollution over the past five years, with PM 2.5 levels decreasing annually, from 57.6 µg/m³ in 2021. December 2024 was notable for having no "very poor" air quality days, unlike previous years, which saw such days.

The decrease in pollution is attributed to a combination of factors. The winter season in 2024 was milder compared to prior years, with lower wind speeds and light rainfall that helped disperse pollutants. These weather conditions prevented the accumulation of airborne particles and improved overall air quality. The absence of thick fog, which often worsens pollution levels in the city during winter months, also contributed to this positive outcome.

In addition to favorable weather, local authorities implemented several measures to improve air quality. The Kolkata Municipal Corporation continued its water-spraying initiatives across key areas of the city to control dust and particulate matter. Furthermore, the Pollution Control Board monitored air quality closely, enforcing regulations to limit industrial emissions, vehicular pollution, and the burning of biomass. These actions were part of a broader effort to reduce the sources of pollution.

Kolkata’s improvement in air quality is part of the National Clean Air Programme, which aims to reduce air pollution levels in cities across India. The city has consistently made progress over the last five years, with a steady decline in PM 2.5 levels each year. The ongoing implementation of pollution control measures, along with public awareness campaigns and stricter enforcement of air quality standards, has contributed to this progress. Kolkata is one of the cities in India where a notable reduction in PM 2.5 levels has been recorded.

The target for further improvement is to reduce the PM 2.5 concentration in Kolkata to below 40 µg/m³. Authorities plan to continue monitoring and controlling air pollution through stricter policies and the use of alternative technologies. Efforts will focus on reducing emissions from vehicles, construction activities, industrial sources, and crop burning, while also encouraging public participation in pollution control efforts. The success seen in 2024 is expected to be built upon in the years ahead, with the goal of achieving sustained improvements in air quality.