SmogRank / South Korea / Busan / Busan

Busan, month by month

Busan has a measured daily mean on 932 days since 23 March 2024. Its worst month was March 2026, at 79 US AQI (23.9 µg/m³), 468th of 2,971 cities on that month's world ranking. Its cleanest was September 2024, at 43 US AQI (7.8 µg/m³). 2025 averaged 62 US AQI (15.2 µg/m³), against 58 US AQI (12.7 µg/m³) in 2024.

Every month since 2024

202458 for the year282 days measured359th of 2,097 in the world
Each square is a month's mean PM2.5 in US AQI from Busan's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Busan marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

1 month
MonthWhy
Mar 20249 of 31 days measured; a month needs 22.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Busan's worst months

MonthUS AQIDays measuredWorld rankEpisode
March 2026 7923.9 µg/m³31 of 31468thof 2,971Japan and South Korea, March 2026
South Korea, 9 to 12 March 2026
January 2025 7622.3 µg/m³31 of 31234thof 2,474Japan and South Korea, 17 to 24 January 2025
South Korea, 13 to 14 January 2025and 1 more
April 2024 7421.5 µg/m³28 of 30183rdof 2,520Japan and South Korea, April 2024
February 2026 7220.2 µg/m³28 of 28549thof 2,866South Korea and Japan, 19 to 21 February 2026
South Korea and Japan, 10 to 15 February 2026and 1 more
March 2025 7119.8 µg/m³31 of 31588thof 2,862Japan and South Korea, March 2025
December 2025 6717.9 µg/m³31 of 31605thof 3,006South Korea, 16 to 20 December 2025
South Korea, 7 December 2025

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Busan's worst days

DayUS AQIEpisode
18 Apr 2024 16169.4 µg/m³Japan and South Korea, April 2024
24 Mar 2026 15560.7 µg/m³Japan and South Korea, March 2026
21 Jan 2025 15358.5 µg/m³Japan and South Korea, 17 to 24 January 2025
19 Apr 2024 15257.0 µg/m³Japan and South Korea, April 2024
27 Mar 2026 13951.0 µg/m³Japan and South Korea, March 2026
23 Jan 2025 13850.5 µg/m³Japan and South Korea, 17 to 24 January 2025
22 Jan 2025 12946.8 µg/m³Japan and South Korea, 17 to 24 January 2025
25 Mar 2025 12946.7 µg/m³Japan and South Korea, March 2025
17 Apr 2024 12846.5 µg/m³Japan and South Korea, April 2024
13 Feb 2026 12545.2 µg/m³South Korea and Japan, 10 to 15 February 2026

Daily means, the highest since 23 Mar 2024; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Busan, South Korea, 23 Mar 2024 – 12 Oct 2026. Monitor data from Korea Air Ministry of Environment via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/kr/busan/history (accessed 12 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Busan now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 18:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).