The Centre’s ambitious attempt to improve air quality in some of India’s most polluted cities suggests that a majority of Indian cities are far from making significant progress. In 49 cities whose particulate matter numbers were consistently available for five years, 27 cities showed a decline in PM 2.5 — considered the most dangerous grade of pollutant — while only four had met or exceeded the targeted decline, according to an analysis by Respirer Living Sciences and Climate Trends, released early on Wednesday.
The stated goal of the ₹9,631-crore National Clean Air Programme (NCAP) is to reduce average particulate matter concentrations 40% by 2026 (compared to 2017) in 131 cities. When the programme was initiated, the aim was to cut pollution 20-40% by 2024 in this cities but this goalpost was later shifted to 2026.
While the deadline is still three years away, some of India’s biggest cities are reporting marginal declines or even increasing pollution loads. Delhi, for instance, has seen average, annual PM 2.5 levels decline only 5.9%. Navi Mumbai, a suburb of Mumbai, has — instead of a decline — seen a 46% rise in PM 2.5 levels; Mumbai — a 38.1% rise and Ujjain, a 46% rise. Jaipur and Visakhapatnam saw PM 2.5 increase 13% and 12% rise respectively and Pune 10%.
Among the cities that showed a sharp decline in PM 2.5 from 2019-2023 were Varanasi, with a 72% average reduction in PM 2.5 levels and 69% reduction in PM 10 levels. Agra too reported a 53% decline as did Jodhpur with a 50% decline. The study analysed data from 99 cities and while there were others that showed declines and rises, only 49 had data worth at least 60 months and for at least five years.
From Uttar Pradesh
“Among other cities that registered a more than 40% reduction in the PM 2.5 levels (as compared to 2019) were Jodhpur (50%), Kanpur (50%), Meerut (42%), and Lucknow (41%). Except for Jodhpur, all cities that have already achieved the 2026 reduction targets are from Uttar Pradesh. With respect to PM 10 levels, apart from Varanasi and Talcher, no other cities have met the 40% reduction target yet,” the study noted.
This study considered average, annual particulate matter concentrations, though pollution levels, it is known, can have significant variation within a year. Delhi and for that matter several cities in northern and eastern India peak during the winter, with adverse meteorological conditions preventing the natural flushing out of particulate matter. Nearly 18 of the top 20 cities with the highest PM 2.5 levels in 2023 are clustered in the Indo-Gangetic Plain (IGP), underscoring the region’s vulnerability to heightened particulate matter concentrations. Only Guwahati and Rourkela, outside the IGP, were among the 20 most polluted cities for PM 2.5, the study added.
Another factor that significantly influences annual concentrations of pollutants in a city is the number and spread of continuous ambient air quality monitors — the devices that track fluctuations in chemical pollutants through the day. While cities such as Mumbai and Delhi have several such stations and spread across the breadth of the cities to account for pollution in areas as diverse as say, the industrial clusters or cleaner, greener parts of town, most Indian cities have only a handful.
Only four of the 92 cities part of the analysis, for instance have more than 10 such stations. Varanasi in 2019 had only one such station, which only worked 24% of the time whereas by 2024 had four stations that were operational all days. The vast majority of Indian cities have less than five stations.
Geographical locations
“...The variations in PM 2.5 and PM 10 observed in the data can also be partly attributed to the geographical locations of the cities analysed, the diverse sources of emissions and meteorological influences, among other factors. The contribution of these factors, particularly the influence of emissions versus meteorology, requires further study,” the authors note. Whether cities’ actions have actually translated to improvement in air quality is as yet unclear.
“The National Clean Air Programme has made noteworthy progress in tackling air pollution, witnessing notable reductions in PM 2.5 and PM 10 levels in top polluted cities, showing there have been efforts under way. Despite these positive strides, persistent challenges exist, with some urban areas facing an uptick in pollution concentrations. The programme’s revised goal of a 40% reduction in particulate matter by 2026 reflects a commitment to ambitious environmental targets. As cities add new air quality monitoring stations, strengthened monitoring will give a better picture of the problem and allow for better mitigation measures,” said Aarti Khosla, Director, Climate Trends.
