SmogRank / History / City race
Cities in Norway, worst air first, day by day
Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.
No city had 21 of the 30 days to 10 Nov 2025 measured.
Not counted on this day, too few days measured: Trondheim since 19 Oct 2025, Sarpsborg since 19 Oct 2025, Porsgrunn since 19 Oct 2025 and 15 more cities.
Cities counted each day
A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.