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 to18 Jul 2023 That day's board

The worst cities for PM2.5 over the 7 days to 18 Jul 2023: Osorno 147.3 µg/m³, Hualpén 114.8 µg/m³ and Nacimiento 113.9 µg/m³.

  1. 1OsornoChile147.3
  2. 2HualpénChile114.8
  3. 3NacimientoChile113.9
  4. 4DushanbeTajikistan109.2
  5. 5CoyhaiqueChile106.0
  6. 6Puerto VarasChile101.5
  7. 7Puerto MonttChile100.8
  8. 8LajaChile95.9
  9. 9Grande PrairieCanada83.1
  10. 10EdmontonCanada82.6
  11. 11San CarlosChile82.0
  12. 12RancaguaChile75.7
  13. 13La UniónChile74.9
  14. 14TemucoChile73.9
  15. 15JakartaIndonesia73.3
  16. 16Fort McMurrayCanada72.8
  17. 17Fort SaskatchewanCanada71.1
  18. 18HualquiChile69.9
  19. 19ChillánChile69.4
  20. 20Los ÁngelesChile64.8

+ 1,266 more cities, 62.8 µg/m³ and below

Not counted on this day, too few days measured: Curanilahue since 17 Jul 2023, Manama since 15 Jul 2023, Prince George since 15 Jul 2023 and 9 more cities. 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 readers for them. Most cities there are missing from this board, not clean. Why.