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.
The worst cities for PM2.5 over the 7 days to 19 Jul 2023: Osorno 130.3 µg/m³, Dushanbe 124.1 µg/m³ and Hualpén 118.2 µg/m³.
- 1OsornoChile130.3
- 2DushanbeTajikistan124.1
- 3HualpénChile118.2
- 4NacimientoChile117.7
- 5CoyhaiqueChile113.7
- 6LajaChile103.3
- 7San CarlosChile88.8
- 8RancaguaChile82.0
- 9EdmontonCanada80.5
- 10Puerto MonttChile80.2
- 11Puerto VarasChile79.6
- 12LinaresChile74.6
- 13HualquiChile73.8
- 14ChillánChile72.3
- 15Fort McMurrayCanada72.0
- 16Fort SaskatchewanCanada69.6
- 17TalaganteChile69.0
- 18La UniónChile67.9
- 19Los ÁngelesChile67.2
- 20RengoChile67.1
+ 1,267 more cities, 67.0 µg/m³ and below
Not counted on this day, too few days measured: Jakarta since 19 Jul 2023, Curanilahue since 17 Jul 2023, Manama since 15 Jul 2023 and 9 more cities. Days missing from the source archive fall in this window, so fewer countries are counted.
Cities counted each 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.