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 to23 Mar 2024 That day's board

The worst cities in Canada for PM2.5 over the 30 days to 23 Mar 2024: Regina 10.7 µg/m³, Prince George 9.1 µg/m³ and Smithers 8.3 µg/m³.

  1. 1ReginaSaskatchewan10.7
  2. 2Prince GeorgeBritish Columbia9.1
  3. 3SmithersBritish Columbia8.3
  4. 4WindsorOntario8.3
  5. 5DuncanBritish Columbia8.0
  6. 6L'Ancienne-LoretteQuebec7.5
  7. 7QuesnelBritish Columbia7.4
  8. 8BécancourQuebec7.3
  9. 9Port AlberniBritish Columbia7.2
  10. 10EstevanSaskatchewan6.9
  11. 11Fort SaskatchewanAlberta6.9
  12. 12HamiltonOntario6.8
  13. 13SaskatoonSaskatchewan6.8
  14. 14VernonBritish Columbia6.8
  15. 15CalgaryAlberta6.7
  16. 16EdmontonAlberta6.6
  17. 17LondonOntario6.6
  18. 18TorontoOntario6.6
  19. 19KamloopsBritish Columbia6.4
  20. 20Red DeerAlberta6.4

+ 89 more cities, the next at 6.4 µg/m³

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.