Bad Air Days in North Slope, Alaska
Not enough data
EPA monitors in North Slope ran on too few days between 2016 and 2025 to give a fair yearly count (about 30% of days covered). Neighbouring counties below are a better guide.
What actually helps here
- EPA monitors here ran too few days to give a fair yearly count. Use AirNow for today's air.
Better or worse than it was
The worst recent year was 2022, with 1 bad day on 100 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2022-07-01 | 170 | PM2.5 |
| 2023-08-07 | 77 | PM2.5 |
| 2025-06-24 | 72 | PM2.5 |
| 2022-07-04 | 71 | PM2.5 |
| 2025-07-21 | 70 | PM2.5 |
Most days, not the worst ones
Across 762 monitored days from 2019 to 2025, the air in North Slope rated Good on 98% of them, more often than the 72% typical of monitored counties, and Moderate on 1%. The median day sat at AQI 6; one day in ten went above 17.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)100%762 days
Year by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 85 | 83 | 2 | 0 | 0 | 7 | 72 |
| 2024 | 120 | 120 | 0 | 0 | 0 | 5 | 32 |
| 2023 | 121 | 120 | 1 | 0 | 0 | 4 | 77 |
| 2022 | 100 | 95 | 4 | 1 | 1 | 7 | 170 |
| 2021 | 114 | 113 | 1 | 0 | 0 | 5 | 53 |
| 2020 | 112 | 111 | 1 | 0 | 0 | 6 | 54 |
| 2019 | 110 | 108 | 2 | 0 | 0 | 6 | 69 |
*2025 may be a partial year in EPA's file.
Elsewhere in Alaska
- Fairbanks North Star37/yr
- Matanuska-Susitna2/yr
- Anchorage1/yr
- Bethel1/yr
- Juneauunder 1/yr
- Kenai Peninsulathin data
- Aleutians Eastthin data
- Denali0/yr
How this is counted
A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day.