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 30 days to 21 Jul 2024: Coyhaique 99.7 µg/m³, Santa María 90.3 µg/m³ and Hualpén 86.5 µg/m³.
- 1CoyhaiqueChile99.7
- 2Santa MaríaPeru90.3
- 3HualpénChile86.5
- 4NacimientoChile78.8
- 5RancaguaChile78.2
- 6VillarricaChile77.1
- 7Puerto VarasChile75.5
- 8OsornoChile74.5
- 9TemucoChile73.1
- 10CuricóChile69.4
- 11RengoChile68.5
- 12TalcahuanoChile63.7
- 13HualquiChile62.0
- 14ChillánChile61.6
- 15La UniónChile60.4
- 16SantiagoChile59.5
- 17Puerto MonttChile58.7
- 18ValdiviaChile58.5
- 19CauquenesChile58.2
- 20CuranilahueChile58.0
+ 2,612 more cities, 57.9 µg/m³ and below
Not counted on this day, too few days measured: Shenyang since 20 Jul 2024, San Carlos since 18 Jul 2024, Quilpué since 22 Jun 2024 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 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.