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.

CountriesCities
The 30 days to27 Jul 2023 That day's board

The worst cities in Canada for PM2.5 over the 30 days to 27 Jul 2023: Fort McMurray 40.6 µg/m³, Fort St. John 38.8 µg/m³ and Edmonton 38.1 µg/m³.

  1. 1Fort McMurrayAlberta40.6
  2. 2Fort St. JohnBritish Columbia38.8
  3. 3EdmontonAlberta38.1
  4. 4Grande PrairieAlberta34.6
  5. 5Fort SaskatchewanAlberta30.7
  6. 6QuesnelBritish Columbia27.8
  7. 7Prince GeorgeBritish Columbia25.9
  8. 8Grand CentreAlberta24.3
  9. 9Red DeerAlberta22.3
  10. 10WindsorOntario21.2
  11. 11St. AlbertAlberta19.9
  12. 12SarniaOntario19.6
  13. 13BarrieOntario19.2
  14. 14BellevilleOntario18.9
  15. 15St. CatharinesOntario18.8
  16. 16ChathamOntario18.5
  17. 17Labrador CityNewfoundland and Labrador18.4
  18. 18Drayton ValleyAlberta18.3
  19. 19PeterboroughOntario18.1
  20. 20CalgaryAlberta17.8

+ 81 more cities, the next at 17.8 µg/m³

Not counted on this day, too few days measured: Bécancour since 15 Jul 2023 and Rouyn-Noranda since 14 Jul 2023. Days missing from the source archive fall in this window, so fewer countries are counted.

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that 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.