SmogRank / Episodes / Switzerland
Bad-air episodes in Switzerland
31 times since January 2023, many cities in Switzerland had air at least twice as dirty as their usual for the time of year on the same days. The largest reached 647 cities: Europe, 6 to 25 February 2023.
8 days. 430 cities; highest daily mean 136 µg/m³ in Łask.
Each bar is an episode: as long as it lasted, as thick as the number of cities it counted, coloured by its highest daily mean. A lane is a part of the world; an episode sits in the lane of the country with most of its cities. Point at a bar or tap one to read it; the years open each year's list.
2026
- Europe, 18 to 25 March 20268 days430 cities136 µg/m³peak, Łask
- Europe, 1 to 12 March 202612 days532 cities109 µg/m³peak, Radomsko
- Europe, January and February 202612 January to 12 February 2026, 32 days625 cities252 µg/m³peak, Travnik
- Eastern Europe, January 20269 to 10 January 2026, 2 days86 cities210 µg/m³peak, Bijelo Polje
- Europe, December 2025 to January 202625 December 2025 to 2 January 2026, 9 days189 cities110 µg/m³peak, Kempten (Allgäu)
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.