Brown, South Dakota Air Quality
Brown County, South Dakota (SD)
↓ Improvingover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days). This area has seen measurable air quality improvement over the decade.
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 29 | 60 | 166 | 289 | 68 | 8 | PM2.5 |
| 2022 | 23 | 45 | 93 | 325 | 25 | 0 | PM2.5 |
| 2021 | 26 | 58 | 208 | 301 | 52 | 3 | PM2.5 |
| 2020 | 28 | 54 | 78 | 308 | 56 | 0 | PM2.5 |
| 2019 | 25 | 53 | 80 | 104 | 18 | 0 | PM2.5 |
| 2018 | 32 | 53 | 421 | 104 | 15 | 2 | PM2.5 |
| 2017 | 31 | 52 | 97 | 108 | 14 | 0 | PM2.5 |
| 2016 | 26 | 53 | 79 | 104 | 15 | 0 | PM2.5 |
| 2015 | 32 | 54 | 94 | 102 | 19 | 0 | PM2.5 |
| 2014 | 29 | 53 | 85 | 103 | 16 | 0 | PM2.5 |
What This Means for Brown County Residents
Brown, South Dakota has received an Air Quality Grade of B (74/100) based on a decade of EPA monitoring data. The current median AQI of 29 falls in the "Good" range.
Encouragingly, air quality here has been improving, with the median AQI dropping by 0 points over the monitoring period. This trend suggests continued investment in emission controls and cleaner energy.
The primary pollutant affecting this area is Fine Particulate Matter (PM2.5). Over the past 5 years, this area has averaged 2 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.