SmogRank / History / City race
Cities, 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.
The worst cities for PM2.5 over the 7 days to 7 Sep 2023: Prince Albert 112.4 µg/m³, Grand Centre 108.7 µg/m³ and Fort McMurray 105.2 µg/m³.
- 1Prince AlbertCanada112.4
- 2Grand CentreCanada108.7
- 3Fort McMurrayCanada105.2
- 4SaskatoonCanada104.5
- 5EdmontonCanada93.2
- 6ReginaCanada80.4
- 7Fort SaskatchewanCanada79.9
- 8Swift CurrentCanada74.6
- 9QuesnelCanada74.3
- 10Flin FlonCanada68.7
- 11OsornoChile68.4
- 12CoyhaiqueChile67.4
- 13Fort St. JohnCanada66.7
- 14Puerto VarasChile63.4
- 15DushanbeTajikistan62.3
- 16DhakaBangladesh60.1
- 17Red DeerCanada58.9
- 18EstevanCanada56.2
- 19PeshawarPakistan51.8
- 20LahorePakistan51.7
+ 2,186 more cities, 51.6 µg/m³ and below
Not counted on this day, too few days measured: Nacimiento since 5 Sep 2023, Alexandria since 3 Sep 2023, Manama since 28 Aug 2023 and 4 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.