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 29 Aug 2023: Puerto Varas 122.2 µg/m³, Osorno 120.8 µg/m³ and Grants Pass 120.4 µg/m³.
- 1Puerto VarasChile122.2
- 2OsornoChile120.8
- 3Grants PassUnited States120.4
- 4YrekaUnited States107.5
- 5MedfordUnited States102.7
- 6AshlandUnited States101.4
- 7TalentUnited States98.2
- 8GreenUnited States90.2
- 9Fort McMurrayCanada88.1
- 10NacimientoChile77.2
- 11La UniónChile65.5
- 12Fort St. JohnCanada59.4
- 13Grande PrairieCanada57.0
- 14Puerto MonttChile56.0
- 15BendUnited States55.0
- 16DhakaBangladesh54.2
- 17Crescent CityUnited States52.2
- 18Los ÁngelesChile51.5
- 19AlexandriaEgypt51.3
- 20ChillánChile50.6
+ 1,634 more cities, the next at 49.2 µg/m³
Not counted on this day, too few days measured: Manama since 28 Aug 2023, Jakarta since 28 Aug 2023, Ash Shīḩānīyah since 27 Aug 2023 and 3 more cities.
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, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.