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.

CountriesCities
The 7 days to27 Jun 2023 That day's board

The worst cities for PM2.5 over the 7 days to 27 Jun 2023: Rouyn-Noranda 141.2 µg/m³, Coyhaique 122.1 µg/m³ and Saguenay 107.7 µg/m³.

  1. 1Rouyn-NorandaCanada141.2
  2. 2CoyhaiqueChile122.1
  3. 3SaguenayCanada107.7
  4. 4North BayCanada100.9
  5. 5Greater SudburyCanada93.2
  6. 6DushanbeTajikistan85.2
  7. 7Labrador CityCanada73.1
  8. 8Sault Ste. MarieCanada64.3
  9. 9TlaquepaqueMexico56.8
  10. 10KigaliRwanda56.3
  11. 11PeshawarPakistan55.4
  12. 12LahorePakistan50.7
  13. 13WaukeshaUnited States50.4
  14. 14Puerto AysénChile49.8
  15. 15GreendaleUnited States47.3
  16. 16South MilwaukeeUnited States47.3
  17. 17JakartaIndonesia46.6
  18. 18Puerto VarasChile45.9
  19. 19MilwaukeeUnited States45.8
  20. 20KalamazooUnited States45.4

+ 1,648 more cities, 45.2 µg/m³ and below

Not counted on this day, too few days measured: Guadalajara since 24 Jun 2023, Johannesburg since 14 Jun 2023, Bloemfontein since 12 Jun 2023 and 8 more cities.

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.