By Manoj Kumar N and Nandikesh Sivalingam
Key highlights
- Compliance: In November 2024, 109 out of 268 cities with more than 80% of the days with continuous ambient air quality monitoring stations (CAAQMS) data available recorded PM2.5 concentrations below India’s National Ambient Air Quality Standards (NAAQS) of 60 µg/m³. Only one city complied with the World Health Organization’s (WHO) daily safe guideline concentration of 15 µg/m³.
- NCAP cities: The monthly average PM2.5 levels in 64 National Clean Air Programme (NCAP) cities (out of 99 cities with more than 80% of days with data) surpassed India’s daily NAAQS for PM2.5, while all 99 cities exceeded the WHO’s daily guideline.
- Non-NCAP cities: Among the 169 non-NCAP cities with over 80% of days with CAAQMS data, 168 cities reported monthly average PM2.5 levels above the WHO daily guideline. 95 cities exceeded the daily NAAQS.
- AQI category: In November 2024, the number of cities with ‘Good’ (0-30 µg/m³) air quality dropped significantly to 32, compared to 79 in October. Meanwhile, cities with ‘Satisfactory’ (31-60 µg/m³) air quality decreased from 135 in October to 77 in November. The number of cities experiencing ‘Moderate’ (61-90 µg/m³) air quality rose to 86 in November, up from 44 in October. There was also a notable increase in cities with ‘Poor’ (91-120 µg/m³) air quality, rising from 5 in October to 50 in November, and 23 cities recorded ‘Very Poor’ (121-250 µg/m³) air quality, compared to 0 in the previous month.
- Most polluted city: Delhi ranked as the most polluted city in India in November 2024, recording a monthly average PM2.5 concentration of 249 µg/m³, surpassing the daily NAAQS limit of 60 µg/m³ 100% of the days in the month.
- Delhi recorded 20 days in the ‘Very Poor’ (121-250 µg/m³) category and 10 days in ‘Severe’ (>250 µg/m³) category.
- The November average is 2.2 times higher than the October average of 111 µg/m³, when there were 5 days in the ‘Satisfactory’ category, 8 days in the ‘Moderate’ category, 4 days in the ‘Poor’ (91-120 µg/m³) category, and 14 days in the ‘Very Poor’ (121-250 µg/m³) category.
- Although stubble burning contributed an average of 19% to PM2.5 levels in Delhi in November, the elevated PM2.5 concentrations point to significant year-round sources. This emphasises the need for a comprehensive long-term strategy that targets pollution at its roots, rather than relying solely on short-term winter measures.
- Haryana accounted for four of India’s top 10 most polluted cities, followed by three cities from Uttar Pradesh, and one each from Bihar, Assam, and Delhi.
- Cleanest city: Aizawl, in the state of Mizoram, was the cleanest city in India during November, with a monthly average PM2.5 of 3 µg/m³.
- The top 10 cleanest cities comprise five cities from Karnataka, three from Tamil Nadu, and one each from Mizoram and Madhya Pradesh.
- Frequency in top 10 polluted cities: A total of 67 cities were featured in the daily top 10 most polluted cities list in November 2024. Of these, 22 cities made an appearance at least five times over the 30-day period, topped by Delhi, which featured the most times (29 days), followed by Hajipur (18 days), Ghaziabad (17 days), Byrnihat (14 days), Bahadurgarh (13 days), Hapur (11 days) and Noida (11 days).
- NCAP: Only 23 out of the 67 cities featured in the daily top 10 most polluted cities list during November 2024 are part of the National Clean Air Programme (NCAP). The remaining 44 cities have no action plan to reduce hazardous air pollution concentrations.
- Megacities: With the exception of Chennai and Bangalore, all other megacities, such as, Delhi, Mumbai, and Kolkata saw all their monthly averages in November exceeding the NAAQS.
- Monitoring infrastructure: There are 558 continuous ambient air quality monitoring stations (CAAQMS) that cover 289 cities. In November 2024, one CAAQMS in New Moti Bagh, Delhi was removed from the list of installed monitoring stations.
Monthly ambient air quality snapshot for India: November 2024
Monthly ambient air quality trends in India: November 2024 air quality snapshot (pdf version)
Press release – Monthly ambient air quality trends in India: November 2024 air quality snapshot
Data sources
Ambient air quality data recorded by Continuous Ambient Air Quality Monitoring Stations (CAAQMS) is downloaded from the ‘Central Control Room for Air Quality Management – All India‘ dashboard operated by the Central Pollution Control Board (CPCB).