Boulogne-sur-Mer Seasonal Pollution
Boulogne-sur-Mer usually records its highest OpenAQ-derived EPA AQI in November and its cleanest month in January. The page uses OpenAQ-derived daily history for 1 mapped monitoring location in Hauts-de-France, France.
Search city analytics
Average EPA AQI
40
Rank 65 of 272 cities by average AQI
PM2.5
8.5
ug/m3 annualized city average
Seasonality
November
Cleanest: January
Health indicator
0.4
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Boulogne-sur-Mer
17
31
42
32
34
39
38
41
45
41
51
51
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Boulogne-sur-Mer, the current global analytics build covers 269 daily rows from 2024-01-29 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.