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 to17 Nov 2023 That day's board

The worst cities in Canada for PM2.5 over the 30 days to 17 Nov 2023: Cranbrook 14.0 µg/m³, Regina 12.4 µg/m³ and Prince George 12.2 µg/m³.

  1. 1CranbrookBritish Columbia14.0
  2. 2ReginaSaskatchewan12.4
  3. 3Prince GeorgeBritish Columbia12.2
  4. 4SmithersBritish Columbia12.0
  5. 5CastlegarBritish Columbia11.7
  6. 6QuesnelBritish Columbia11.7
  7. 7VernonBritish Columbia11.4
  8. 8EdmontonAlberta11.3
  9. 9DuncanBritish Columbia11.0
  10. 10Fort SaskatchewanAlberta9.6
  11. 11CourtenayBritish Columbia9.4
  12. 12WindsorOntario9.4
  13. 13CalgaryAlberta9.2
  14. 14Port AlberniBritish Columbia9.2
  15. 15Grande PrairieAlberta9.1
  16. 16KamloopsBritish Columbia8.9
  17. 17TerraceBritish Columbia8.8
  18. 18HarewoodBritish Columbia8.7
  19. 19LangfordBritish Columbia8.4
  20. 20LondonOntario8.3

+ 96 more cities, 8.3 µg/m³ and below

Not counted on this day, too few days measured: Creston since 11 Nov 2023, Bécancour since 29 Oct 2023 and Flin Flon since 11 Oct 2023.

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 readers for them. Most cities there are missing from this board, not clean. Why.