SmogRank / World / Europe / Norway / Østfold
Most polluted cities in Østfold, Norway
No city in Østfold, Norway has enough readings to rank so far this year.
A city joins this ranking with enough days of readings so far this year; none here has that right now, so there is nothing to map or chart.
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
Estimated: cities without a monitor
Østfold cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.
| City | 7-day estimate |
|---|---|
| Halden | ≈ 6 µg/m³ |
Bad-air episodes in Østfold
- Europe, 1 to 12 March 202612 days532 cities109 µg/m³peak, Radomsko
- Germany, Poland and 25 more countries, March 20253 to 13 March 2025, 11 days553 cities152 µg/m³peak, Negotin
- Europe, 14 February to 1 March 202516 days619 cities178 µg/m³peak, Krotoszyn
- Southern Norway, 12 to 13 January 20252 days8 cities47 µg/m³peak, Drammen
- Southern Norway, 4 January 20251 day10 cities56 µg/m³peak, Fredrikstad
- Southern Norway, 18 to 20 January 20243 days10 cities78 µg/m³peak, Drammen
Times when many cities around here had PM2.5 at twice their usual or more on the same days.
Updated 2026-10-06 22:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.