SmogRank / Episodes / South Korea
Gyeonggi-do and Chungcheongnam-do, South Korea, March 2025
For 3 days, from 9 to 11 March 2025, 38 cities in South Korea had PM2.5 at least twice their usual for the time of year. The worst reading was Seonghwan, Chungcheongnam-do, South Korea: 62.4 µg/m³ on 10 March, about 2.5× its usual 24.9.
Day by day
How it spread
Every city it reached
| City | Days | Highest | Above usual |
|---|---|---|---|
| AnseongGyeonggi-do, South Korea | 3 | 54.510 March | 2.9× |
| Seongnam-siGyeonggi-do, South Korea | 2 | 54.110 March | 2.8× |
| Anyang-siGyeonggi-do, South Korea | 2 | 57.410 March | 2.8× |
| GwangmyeongGyeonggi-do, South Korea | 3 | 58.310 March | 2.8× |
| SuwonGyeonggi-do, South Korea | 2 | 59.110 March | 2.8× |
| Goyang-siGyeonggi-do, South Korea | 2 | 56.310 March | 2.7× |
| PyeongtaekGyeonggi-do, South Korea | 2 | 56.110 March | 2.6× |
| HanamGyeonggi-do, South Korea | 2 | 52.810 March | 2.6× |
| Ansan-siGyeonggi-do, South Korea | 1 | 57.310 March | 2.6× |
| Bucheon-siGyeonggi-do, South Korea | 3 | 58.510 March | 2.6× |
| IncheonIncheon, South Korea | 2 | 60.410 March | 2.6× |
| OsanGyeonggi-do, South Korea | 2 | 53.010 March | 2.6× |
| GwangjuGyeonggi-do, South Korea | 2 | 52.910 March | 2.6× |
| BuyeoChungcheongnam-do, South Korea | 3 | 42.810 March | 2.6× |
| SeoulSeoul, South Korea | 2 | 54.110 March | 2.5× |
| SeonghwanChungcheongnam-do, South Korea | 1 | 62.410 March | 2.5× |
| CheonanChungcheongnam-do, South Korea | 1 | 50.810 March | 2.5× |
| Uijeongbu-siGyeonggi-do, South Korea | 1 | 48.710 March | 2.5× |
| MunsanGyeonggi-do, South Korea | 1 | 52.810 March | 2.4× |
| YangjuGyeonggi-do, South Korea | 1 | 43.07 March | 2.4× |
| Gimpo-siGyeonggi-do, South Korea | 1 | 54.210 March | 2.4× |
| Guri-siGyeonggi-do, South Korea | 2 | 48.210 March | 2.4× |
| AsanChungcheongnam-do, South Korea | 1 | 54.010 March | 2.3× |
| TangjinChungcheongnam-do, South Korea | 1 | 54.410 March | 2.3× |
| Hwaseong-siGyeonggi-do, South Korea | 1 | 52.210 March | 2.3× |
| YesanChungcheongnam-do, South Korea | 1 | 54.810 March | 2.2× |
| SejongSejong-si, South Korea | 2 | 46.810 March | 2.2× |
| BoryeongChungcheongnam-do, South Korea | 1 | 45.112 March | 2.2× |
| HongseongChungcheongnam-do, South Korea | 1 | 49.710 March | 2.2× |
| SeosanChungcheongnam-do, South Korea | 2 | 41.210 March | 2.2× |
| Icheon-siGyeonggi-do, South Korea | 2 | 50.111 March | 2.2× |
| WabuGyeonggi-do, South Korea | 1 | 39.910 March | 2.1× |
| PubalGyeonggi-do, South Korea | 1 | 56.511 March | 2.1× |
| NamyangjuGyeonggi-do, South Korea | 1 | 41.57 March | 2.1× |
| Cheongju-siNorth Chungcheong, South Korea | 1 | 45.311 March | 2.0× |
| Yangp'yŏngGyeonggi-do, South Korea | 1 | 45.210 March | 2.0× |
| YeonggwangJeollanam-do, South Korea | 1 | 32.59 March | 2.0× |
| JungpyongNorth Chungcheong, South Korea | 1 | 44.411 March | 2.0× |
Daily means in µg/m³. Usual: the city's median for this time of year (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that.
Against other episodes in South Korea
Number 26 of 43 episodes in South Korea since our records began, by cities reached.
- Japan and South Korea, March 2025454
- Japan and South Korea, March 2026305
- Japan and South Korea, January 2025274
- Japan and South Korea, February and March 2025192
- South Korea and Japan, January 2026169
- South Korea and Japan, February 2026147
- South Korea, February 2025132
- South Korea, November 2025128
- South Korea, February 2026121
- South Korea, December 2025113
- South Korea, January 2025113
- South Korea, December 2025107
- Gyeonggi-do and Chungcheongnam-do, South Korea, March 202538
Bars: cities reached; colour: the level of the episode's highest daily reading. All 43.
Use this page
SmogRank, Gyeonggi-do and Chungcheongnam-do, South Korea, March 2025: 38 cities with PM2.5 at twice their usual or more, 9 to 11 March 2025, smogrank.com/episodes/2025-03-gyeonggi-do-and-chungcheongnam-do-south-korea (accessed 2 October 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.
An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes. Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.