Ghaziabad most polluted city in India: CSE

New Delhi: According to the All-India winter air quality analysis, Ghaziabad is the most polluted city in the country, while Aizwal and Shillong are the least polluted cities.

As per the report, Delhi was the second most polluted city, followed by Noida, Faridabad, Greater Noida, and Gurugram.

According to an all-India winter air quality analysis done by the Centre for Science and Environment (CSE), particulate pollution spiked and stayed elevated with varying intensities across all regions during the winter of 2021-22 (15 October to 28 February).

The analysis has been done for the 2021–22 winter air quality tracker initiative of CSE’s Urban Data Analytics Lab. 

The report said the most polluted city in the region during winter was Ghaziabad, with a winter average of 178 g/m3,followed by Delhi, which had a winter average of 170 g/m³.

The next eight spots are all occupied by neighboring NCR cities, namely Faridabad, Manesar, Bagpat, Noida, Gurugram, Meerut, and Hapur. Cities in the NCR completely dominated the list of the most polluted. Hisar is the most polluted city in the north outside NCR with a winter average of 142 ug/m3, followed by Firozabad, Moradabad, and Vrindavan—all in the immediate vicinity of NCR, “it said.”

The CSE, however, observed that the north Indian cities recorded an average 11 per cent lower PM2.5 levels last winter, but the improvement in the sub-region of Delhi-NCR was just about eight per cent.

Delhi-NCR also saw a marginal increase in the average peak 24-hour pollution. The peak pollution rose significantly from the baseline among the cities in the south (24 per cent) and central Indian cities (7 per cent) despite the overall fall in the winter average. ” It said,

In terms of the least polluted cities, according to the report, Srinagar is the cleanest city in the north.

Palwal in Haryana, Bhatinda in Punjab, and Alwar in Rajasthan are the other cities with a relatively lower winter average. Interestingly, the peak pollution exceeded the standard of 60 g/m³ in all the cities.

In the eastern region, the report said Siwan was the most polluted city in the region with a winter average of 187 g/m³, while in the western region, it indicates that Ankleshwar in Gujarat saw a jump of 20 per cent in the winter average and a 52 per cent increase in peak.

Nagpur, Maharashtra, saw a 9% increase in winter average and a 78% increase in peak temperatures.Nashik, Maharashtra, saw a 7% increase in winter average and a 10% increase in peak temperatures.

The southern region recorded the lowest regional PM_2.5 average this winter, but it also registered an almost 24 per cent increase in regional average peak pollution compared to the previous winter. “it said. Industrial towns in the south, namely Gummidipoondi in Tamil Nadu and Gadag in Karnataka, also appear in the worst 10 cities for peak pollution (24-hr value).

In the northeastern region, Guwahati was the most polluted city in the region with a winter average of 81 g/m³. This is followed by Agartala, which registered a winter average of 77 g/m³.

“Aizawl and Shillong had the lowest levels compared to all other cities in all regions this winter,” it said.

“Clearly, the winter pollution challenge is not limited to mega cities or to one specific region; it is now a widespread national problem that requires urgent and deliberate action on a national scale. This requires quicker reforms and action in key sectors of pollution – vehicles, industry, power plants, and waste management – to bend the annual air pollution curve and daily spikes, “says Anumita Roychowdhury, executive director, research and advocacy, CSE.

As the availability of real-time air quality data has improved in several regions with the expansion of air quality monitoring systems, it has become possible to assess the regional differences and the unique regional trends. This can help to inform the regional clean air action, “says Avikal Somvanshi, programme manager, Urban Data Analytics Lab, CSE. 

This air quality tracker initiative has helped benchmark the winter air quality for peer-to-peer comparison within each region and inter-regional differences, the CSE said.

The analysis is based on publicly available granular real-time data (15-minute averages) from the Central Pollution Control Board’s (CPCB) official online portal, Central Control Room for Air Quality Management. The data is captured from 326 official stations under the Continuous Ambient Air Quality Monitoring System (CAAQMS) spread across 161 cities in 26 states and Union territories, it said.