Bielefeld Seasonal Pollution
Bielefeld usually records its highest OpenAQ-derived EPA AQI in March and its cleanest month in July. The page uses OpenAQ-derived daily history for 2 mapped monitoring locations in North Rhine-Westphalia, Germany.
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Average EPA AQI
41
Rank 117 of 297 cities by average AQI
PM2.5
8.6
ug/m3 annualized city average
Seasonality
March
Cleanest: July
Health indicator
0.4
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Bielefeld
47
41
61
32
43
40
31
39
43
37
45
41
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Bielefeld, the current global analytics build covers 340 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.