Basel Seasonal Pollution
Basel usually records its highest OpenAQ-derived EPA AQI in January and its cleanest month in May. The page uses OpenAQ-derived daily history for 2 mapped monitoring locations in Basel-Stadt, Switzerland.
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Average EPA AQI
12
Rank 22 of 33 cities by average AQI
PM2.5
n/a
ug/m3 annualized city average
Seasonality
January
Cleanest: May
Health indicator
n/a
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Basel
17
11
16
-
7
13
10
10
11
10
14
14
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Basel, the current global analytics build covers 257 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.