Riehen Seasonal Pollution
Riehen usually records its highest OpenAQ-derived EPA AQI in January and its cleanest month in May. The page uses OpenAQ-derived daily history for 3 mapped monitoring locations in Basel-Stadt, Switzerland.
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Average EPA AQI
46
Rank 11 of 33 cities by average AQI
PM2.5
10.8
ug/m3 annualized city average
Seasonality
January
Cleanest: May
Health indicator
0.5
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Riehen
66
46
47
33
29
43
34
47
42
45
60
59
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Riehen, the current global analytics build covers 363 daily rows from 2024-01-01 to 2024-12-31. The calculations normalize PM2.5 and PM10 observations into US EPA AQI bands so country, city, and tool pages use one consistent method.