Bad-air episodes in India
5 times since January 2023, many cities in India had air at least twice as dirty as their usual for the time of year on the same days. The largest reached 58 cities: North-western India, September 2026.
2026
- North-eastern India, September 202628 to 29 September 2026, 2 days10 cities65Kolkata
- North-western India, September 202619 to 25 September 2026, 7 days58 cities170Gurugram
- Odisha and Chhattisgarh, India, September 202615 to 17 September 2026, 3 days11 cities79Belpahar
- Haryana and Punjab, India, September 20268 to 10 September 2026, 3 days9 cities139Panipat
- North-eastern India, September 20264 to 9 September 2026, 6 days14 cities107Bihār Sharīf
Each row: one bar per day, as tall as the number of cities counted that day and coloured by their median level; the number of cities; the highest daily reading and where. An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes.