SmogRank / Episodes / South Korea

South Korea, 1 to 2 February 2025

For 2 days, from 1 to 2 February 2025, 11 cities in South Korea had PM2.5 at least twice their usual for the time of year. The worst reading was Hongseong, Chungcheongnam-do, South Korea: 62.8 µg/m³ on 1 February, about 2.8× its usual 22.8.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached11in 1 country
Days21 to 2 February 2025
Worst day2 February10 cities counted
Furthest above usual2.8×Hongseong

Day by day

2 February 10 cities at twice their usual or more
GunsanBuanKimjeIksanJeongeupNamsaYŏnmuWanjuJeonjuJangseongNonsanDamyangImsilMasanGongjuGwangjuNajuJinan-gunHwasunDaejeonNangenKinzanTangjinAsanChangsuSejongMokpoTaesal-liYeongamCheonanOkcheonKuryeSeonghwanCheongju-siPyeongtaekBoseongJangheungYeongdongBeolgyoChinch'ŏnAnseongSuncheonOsanJungpyongKwangyangAnsan-siSuwonHadongGwangyangAnyang-siIncheonKoesanYeosuGimcheonGwangmyeongBucheon-siSeongnam-siIcheon-siGwangjuPubalChinjuSangjuSeoulGimpo-siChungjuHanamGoyang-siYeojuGuri-siMungyeongGumiWabuGanghwa-gunYangp'yŏngNamyangjuWaegwanUijeongbu-siHwadoMunsanHwawŏnChangnyeongYangjuGoseongWŏnjuDaeguYecheonKunwiNaesŏTongyeongGapyeongGyeongsan-siHongch’ŏnChangwonMiryangHayangAndongYeongjuChuncheonSinhyeonNeietsuJeju CityEisenCheorwonGaigeturiGeojeKimhaeHwacheonYangsanCheongsong gunBusanYangguUngsangGyeongjuGijangT’aebaekYeonilUlsanPohangGangneungJumunjinDonghae CitySantyokuSokchoTsushimaIkiKaratsuItoshimaMaebaru-chūōKogaFukuokaMunakataKasugaWakasugiKogaNakamaNōgataIizukaKitakyushuTagawaMuanHaenamSinanKoch'angYesanYeonggwangBuyeoBoryeongSeosanHwaseong-siHongseong
29 Jan30311 Feb2345
Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.

How it spread

HongseongHongseong, 29 January: 8.2 µg/m³Hongseong, 30 January: 12.5 µg/m³Hongseong, 31 January: 38.7 µg/m³Hongseong, 1 February: 62.8 µg/m³, 2.8× its usual 22.8Hongseong, 2 February: 55.1 µg/m³, 2.4× its usual 22.8Hongseong, 3 February: 18.9 µg/m³Hongseong, 4 February: 7.4 µg/m³Hongseong, 5 February: 7.5 µg/m³BoryeongBoryeong, 29 January: 10.8 µg/m³Boryeong, 30 January: 17.8 µg/m³Boryeong, 31 January: 31.7 µg/m³Boryeong, 1 February: 43.0 µg/m³, 2.2× its usual 19.8Boryeong, 2 February: 42.7 µg/m³, 2.1× its usual 19.9Boryeong, 3 February: 17.9 µg/m³Boryeong, 4 February: 6.4 µg/m³Boryeong, 5 February: 8.5 µg/m³SeosanSeosan, 29 January: 12.2 µg/m³Seosan, 30 January: 18.0 µg/m³Seosan, 31 January: 32.5 µg/m³Seosan, 1 February: 40.8 µg/m³, 2.3× its usual 17.5Seosan, 2 February: 37.4 µg/m³, 2.1× its usual 17.7Seosan, 3 February: 12.8 µg/m³Seosan, 4 February: 6.0 µg/m³Seosan, 5 February: 6.3 µg/m³BuyeoBuyeo, 29 January: 12.4 µg/m³Buyeo, 30 January: 21.9 µg/m³Buyeo, 31 January: 35.3 µg/m³Buyeo, 1 February: 36.4 µg/m³, 2.2× its usual 16.8Buyeo, 2 February: 32.2 µg/m³Buyeo, 3 February: 13.9 µg/m³Buyeo, 4 February: 6.7 µg/m³Buyeo, 5 February: 10.3 µg/m³Hwaseong-siHwaseong-si, 29 January: 13.0 µg/m³Hwaseong-si, 30 January: 10.9 µg/m³Hwaseong-si, 31 January: 23.2 µg/m³Hwaseong-si, 1 February: 32.4 µg/m³Hwaseong-si, 2 February: 44.9 µg/m³, 2.5× its usual 17.9Hwaseong-si, 3 February: 8.8 µg/m³Hwaseong-si, 4 February: 5.4 µg/m³Hwaseong-si, 5 February: 6.7 µg/m³YesanYesan, 29 January: 13.3 µg/m³Yesan, 30 January: 19.0 µg/m³Yesan, 31 January: 33.2 µg/m³Yesan, 1 February: 42.7 µg/m³Yesan, 2 February: 44.8 µg/m³, 2.1× its usual 21.8Yesan, 3 February: 16.9 µg/m³Yesan, 4 February: 5.9 µg/m³Yesan, 5 February: 9.8 µg/m³HaenamHaenam, 29 January: 10.8 µg/m³Haenam, 30 January: 10.1 µg/m³Haenam, 31 January: 12.5 µg/m³Haenam, 1 February: 9.2 µg/m³Haenam, 2 February: 33.7 µg/m³, 2.0× its usual 16.7Haenam, 3 February: 18.6 µg/m³Haenam, 4 February: 8.5 µg/m³Haenam, 5 February: 12.2 µg/m³YeonggwangYeonggwang, 29 January: 6.9 µg/m³Yeonggwang, 30 January: 8.7 µg/m³Yeonggwang, 31 January: 11.7 µg/m³Yeonggwang, 1 February: 17.9 µg/m³Yeonggwang, 2 February: 33.4 µg/m³, 2.2× its usual 15.2Yeonggwang, 3 February: 16.0 µg/m³Yeonggwang, 4 February: 4.2 µg/m³Yeonggwang, 5 February: 6.6 µg/m³Koch'angKoch'ang, 29 January: 4.7 µg/m³Koch'ang, 30 January: 5.3 µg/m³Koch'ang, 31 January: 5.8 µg/m³Koch'ang, 1 February: 15.9 µg/m³Koch'ang, 2 February: 31.3 µg/m³, 2.1× its usual 14.9Koch'ang, 3 February: 10.2 µg/m³Koch'ang, 4 February: 2.6 µg/m³Koch'ang, 5 February: 6.1 µg/m³MuanMuan, 29 January: 9.5 µg/m³Muan, 30 January: 10.2 µg/m³Muan, 31 January: 13.0 µg/m³Muan, 1 February: 13.8 µg/m³Muan, 2 February: 26.7 µg/m³, 2.0× its usual 13.3Muan, 3 February: 15.3 µg/m³Muan, 4 February: 6.4 µg/m³Muan, 5 February: 9.3 µg/m³SinanSinan, 29 January: 7.0 µg/m³Sinan, 30 January: 7.3 µg/m³Sinan, 31 January: 9.2 µg/m³Sinan, 1 February: 15.9 µg/m³Sinan, 2 February: 26.1 µg/m³, 2.1× its usual 12.2Sinan, 3 February: 19.2 µg/m³Sinan, 4 February: 3.1 µg/m³Sinan, 5 February: 6.8 µg/m³29 Jan30311 Feb2345
Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

Every city it reached

CityDaysHighestUsualAbove usual
HongseongChungcheongnam-do, South Korea2 62.81 February22.82.8×
Hwaseong-siGyeonggi-do, South Korea1 44.92 February17.92.5×
SeosanChungcheongnam-do, South Korea2 40.81 February17.52.3×
BoryeongChungcheongnam-do, South Korea2 43.01 February19.82.2×
BuyeoChungcheongnam-do, South Korea1 36.41 February16.82.2×
YeonggwangJeollanam-do, South Korea1 33.42 February15.22.2×
YesanChungcheongnam-do, South Korea1 44.82 February21.82.1×
Koch'angJeollabuk-do, South Korea1 31.32 February14.92.1×
SinanJeollanam-do, South Korea1 26.12 February12.22.1×
HaenamJeollanam-do, South Korea1 33.72 February16.72.0×
MuanJeollanam-do, South Korea1 26.72 February13.32.0×

Daily means in µg/m³, over the days each city counted in this episode. Highest: its highest of those days. Usual: the city's median for the time of year of that day (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that, with a usual under 5 µg/m³ taken as 5.

Against other episodes in South Korea

Number 59 of 63 episodes in South Korea since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 63.

Use this page

SmogRank, South Korea, 1 to 2 February 2025: 11 cities with PM2.5 at twice their usual or more, 1 to 2 February 2025, smogrank.com/episodes/2025-02-01-south-korea (accessed 4 October 2026).

Download top 10 (PNG)

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.