SmogRank / History / City race
Cities in Canada, 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 in Canada for PM2.5 over the 30 days to 22 Apr 2024: Calgary 7.3 µg/m³, Estevan 7.2 µg/m³ and Regina 7.2 µg/m³.
- 1CalgaryAlberta7.3
- 2EstevanSaskatchewan7.2
- 3ReginaSaskatchewan7.2
- 4SmithersBritish Columbia7.0
- 5Fort SaskatchewanAlberta6.9
- 6SaskatoonSaskatchewan6.9
- 7Prince GeorgeBritish Columbia6.8
- 8DuncanBritish Columbia6.4
- 9Red DeerAlberta6.3
- 10QuesnelBritish Columbia6.2
- 11SaguenayQuebec6.0
- 12Swift CurrentSaskatchewan5.9
- 13WindsorOntario5.8
- 14ChilliwackBritish Columbia5.7
- 15HamiltonOntario5.7
- 16LangfordBritish Columbia5.7
- 17EdmontonAlberta5.6
- 18Prince AlbertSaskatchewan5.6
- 19VernonBritish Columbia5.6
- 20SquamishBritish Columbia5.4
+ 91 more cities, the next at 5.0 µg/m³
Not counted on this day, too few days measured: St. Thomas since 10 Apr 2024 and Bécancour since 28 Mar 2024.
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 reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.