The summer of 2022 was not only unusually hot but also uncharacteristically high on particulate pollution, especially in north India. High PM2.5levels were observed across multiple cities and regions, and pollution has not been confined to a few mega cities or a specific region — it is a widespread national problem.
This has emerged from the analysis of summer air quality undertaken as part of the air quality tracker initiative of the Urban Lab at Centre for Science and Environment (CSE). Summer days from March 1 to May 31 have been considered for the analysis, as rains had set in during June in several regions.
As availability of real time air quality data has improved in several regions with expansion of the air quality monitoring systems, it has become possible to assess the regional differences and understand the unique regional trends.
“This analysis identifies the unique patterns of pollution across all regions and puts a spotlight on a large number of towns and cities that do not get policy attention. Summer particulate pollution spikes due to arid conditions, high summer heat and temperature, and more airborne dust particles that travel long distances compounding the problem from local sources,” says Anumita Roychowdhury, executive director, research and advocacy, CSE.
Within North India, Delhi NCR was found to be most polluted sub-region. The cities of Delhi-NCR recorded very high summer PM2.5 averages, with Bhiwadi reporting the highest summer average of 134 µg/m³. Manesar (119 µg/m³), Ghaziabad (101 µg/m³), Delhi (97 µg/m³), Gurugram (94 µg/m³) and Noida (80 µg/m³). The PM2.5average of NCR region is almost three times the average of the cities in southern India.
Bhiwadi in Rajasthan was the most polluted city in India this summer with seasonal average of 134 µg/m³. Manesar in Haryana was the second most polluted city with a seasonal average of 119 µg/m³. Singrauli in Madhya Pradesh is the third most polluted city with seasonal average of 110 µg/m³. Rohtak, Haryana and Muzaffarnagar, UP are the other cities in the top five most polluted cities.
12 cities of Delhi-NCR feature in top 20 cities with highest pollution levels this summer. From peak summer pollution perspective Northern Haryana cities completely dominate the list of most polluted with significantly worse 24-hr averages compared to rest of the cities. Aizwal in Mizoram and Gummidipoondi in Tamil Nadu were the least polluted cities in the country this summer.
