SmogRank / History / Country race

Countries, worst air first, day by day

Each country's typical measured city over the 30 days to every day since January 2023, worst first. Press Play to watch the order change, or drag the slider to any day.

CountriesCities
The 30 days to2 Mar 2023 That day's board

The worst countries for PM2.5 over the 30 days to 2 Mar 2023: North Macedonia 43.9 µg/m³, Slovenia 32.0 µg/m³ and Bosnia and Herzegovina 27.2 µg/m³.

  1. 1North Macedonia11 cities43.9
  2. 2Slovenia8 cities32.0
  3. 3Bosnia and Herzegovina4 cities27.2
  4. 4Romania7 cities25.0
  5. 5Poland69 cities22.6
  6. 6Slovakia33 cities19.9
  7. 7Greece9 cities19.7
  8. 8Czechia36 cities18.5
  9. 9Italy35 cities17.6
  10. 10France129 cities17.0
  11. 11Belgium34 cities16.6
  12. 12Austria17 cities14.7
  13. 13The Netherlands27 cities13.6
  14. 14Germany172 cities13.3
  15. 15Spain88 cities12.2
  16. 16Latvia4 cities10.3
  17. 17Portugal7 cities9.7
  18. 18Norway17 cities9.6
  19. 19Brazil17 cities8.2
  20. 20Lithuania3 cities8.1

+ 5 more countries, the next at 7.8 µg/m³

  1. 21United States423 cities7.8

Not counted on this day, too few cities measured: Bulgaria since 6 Feb 2023, United Kingdom since 6 Feb 2023, Canada since 5 Feb 2023 and 10 more countries. Days missing from the source archive fall in this window, so fewer countries are counted.

30 days7 days
GoodModerateUnhealthy for sensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that day

A country's number is its typical measured city: the median of its cities' means over the 30 days (a city needs 21 of them measured; 5 of 7 on the 7-day race), shown only with 3 such cities. A country whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air; "was" beside a city count marks a month after many cities joined or left. 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.