Seoul Seasonal Pollution
Seoul usually records its highest OpenAQ-derived EPA AQI in March and its cleanest month in September. The page uses OpenAQ-derived daily history for 24 mapped monitoring locations in Seoul, South Korea.
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Average EPA AQI
63
Rank 20 of 100 cities by average AQI
PM2.5
16.9
ug/m3 annualized city average
Seasonality
March
Cleanest: September
Health indicator
0.8
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Seoul
-
-
83
75
62
68
52
63
43
55
64
70
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Seoul, the current global analytics build covers 297 daily rows from 2024-02-28 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.