SmogRank / Episodes / Taiwan
Taiwan, February 2025
For 1 day, on 17 February 2025, 21 cities in Taiwan had PM2.5 at least twice their usual for the time of year. The worst reading was Jincheng, Fukien, Taiwan: 47.5 µg/m³ on 17 February, about 2.1× its usual 22.9.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 21 in 1 country
Days 1 17 February 2025
Worst day 17 February 21 cities counted
Furthest above usual 6.2× Sanzhi
Day by day
Play 17 February 21 cities at twice their usual or more
Buzi Yuanlin Xizhou Taichung Nantou Douliu Zhushan Miaoli Taibao Puli Zhudong Yongkang Tainan Hualien City Fengshan Kaohsiung Chaozhou Taitung Hengchun Ishigaki Toufen Chiayi City Jincheng Erlin Erlun Beigang Daxi Changhua Hsinchu Neili Xinying Shulin Zhubei Magong Taipei New Taipei City Taoyuan Xizhi Keelung Yilan Sanzhi 14 Feb 15 16 17 18 19 20 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
Toufen Toufen, 14 February: 30.7 µg/m³, 2.2× usual Toufen, 15 February: 25.7 µg/m³, 1.9× usual Toufen, 16 February: 25.0 µg/m³, 1.8× usual Toufen, 17 February: 28.0 µg/m³, 2.0× usual Toufen, 18 February: 14.1 µg/m³, 1.0× usual Toufen, 19 February: 7.4 µg/m³, 0.5× usual Toufen, 20 February: 17.3 µg/m³, 1.3× usual Jincheng Jincheng, 14 February: 24.1 µg/m³, 1.1× usual Jincheng, 15 February: 27.3 µg/m³, 1.2× usual Jincheng, 16 February: 46.2 µg/m³, 2.0× usual Jincheng, 17 February: 47.5 µg/m³, 2.1× usual Jincheng, 18 February: 23.3 µg/m³, 1.0× usual Jincheng, 19 February: 17.8 µg/m³, 0.8× usual Jincheng, 20 February: 14.3 µg/m³, 0.6× usual Chiayi City Chiayi City, 14 February: 18.9 µg/m³, 0.9× usual Chiayi City, 15 February: 27.9 µg/m³, 1.3× usual Chiayi City, 16 February: 36.5 µg/m³, 1.7× usual Chiayi City, 17 February: 45.7 µg/m³, 2.1× usual Chiayi City, 18 February: 39.0 µg/m³, 1.8× usual Chiayi City, 19 February: 21.5 µg/m³, 1.0× usual Chiayi City, 20 February: 34.0 µg/m³, 1.6× usual Xinying Xinying, 14 February: 19.3 µg/m³, 1.0× usual Xinying, 15 February: 25.6 µg/m³, 1.3× usual Xinying, 16 February: 33.8 µg/m³, 1.8× usual Xinying, 17 February: 45.1 µg/m³, 2.4× usual Xinying, 18 February: 33.9 µg/m³, 1.8× usual Xinying, 19 February: 19.4 µg/m³, 1.0× usual Xinying, 20 February: 29.0 µg/m³, 1.5× usual Erlun Erlun, 14 February: 16.4 µg/m³, 0.8× usual Erlun, 15 February: 25.4 µg/m³, 1.3× usual Erlun, 16 February: 31.5 µg/m³, 1.6× usual Erlun, 17 February: 42.4 µg/m³, 2.1× usual Erlun, 18 February: 27.0 µg/m³, 1.4× usual Erlun, 19 February: 17.1 µg/m³, 0.9× usual Erlun, 20 February: 21.3 µg/m³, 1.1× usual Beigang Beigang, 14 February: 15.4 µg/m³, 0.8× usual Beigang, 15 February: 23.3 µg/m³, 1.2× usual Beigang, 16 February: 29.3 µg/m³, 1.6× usual Beigang, 17 February: 39.9 µg/m³, 2.1× usual Beigang, 18 February: 28.1 µg/m³, 1.5× usual Beigang, 19 February: 15.5 µg/m³, 0.8× usual Beigang, 20 February: 23.0 µg/m³, 1.2× usual Magong Magong, 14 February: 16.8 µg/m³, 1.2× usual Magong, 15 February: 11.7 µg/m³, 0.8× usual Magong, 16 February: 13.9 µg/m³, 1.0× usual Magong, 17 February: 38.2 µg/m³, 2.8× usual Magong, 18 February: 16.5 µg/m³, 1.2× usual Magong, 19 February: 17.4 µg/m³, 1.3× usual Magong, 20 February: 13.2 µg/m³, 1.0× usual Erlin Erlin, 14 February: 11.1 µg/m³, 0.6× usual Erlin, 15 February: 19.0 µg/m³, 1.0× usual Erlin, 16 February: 24.8 µg/m³, 1.3× usual Erlin, 17 February: 38.2 µg/m³, 2.1× usual Erlin, 18 February: 19.0 µg/m³, 1.0× usual Erlin, 19 February: 13.0 µg/m³, 0.7× usual Erlin, 20 February: 15.8 µg/m³, 0.9× usual Xizhi Xizhi, 14 February: 8.5 µg/m³, 0.7× usual Xizhi, 15 February: 15.9 µg/m³, 1.3× usual Xizhi, 16 February: 22.4 µg/m³, 1.8× usual Xizhi, 17 February: 37.5 µg/m³, 3.0× usual Xizhi, 18 February: 12.0 µg/m³, 0.9× usual Xizhi, 19 February: 11.3 µg/m³, 0.9× usual Xizhi, 20 February: 10.3 µg/m³, 0.8× usual Keelung Keelung, 14 February: 6.5 µg/m³, 0.5× usual Keelung, 15 February: 10.4 µg/m³, 0.9× usual Keelung, 16 February: 18.1 µg/m³, 1.5× usual Keelung, 17 February: 36.8 µg/m³, 3.1× usual Keelung, 18 February: 9.7 µg/m³, 0.8× usual Keelung, 19 February: 9.4 µg/m³, 0.8× usual Keelung, 20 February: 8.8 µg/m³, 0.7× usual Taipei Taipei, 14 February: 7.8 µg/m³, 0.6× usual Taipei, 15 February: 16.9 µg/m³, 1.3× usual Taipei, 16 February: 21.4 µg/m³, 1.6× usual Taipei, 17 February: 36.8 µg/m³, 2.8× usual Taipei, 18 February: 12.3 µg/m³, 0.9× usual Taipei, 19 February: 11.0 µg/m³, 0.8× usual Taipei, 20 February: 10.9 µg/m³, 0.8× usual New Taipei City New Taipei City, 14 February: 6.4 µg/m³, 0.5× usual New Taipei City, 15 February: 16.0 µg/m³, 1.3× usual New Taipei City, 16 February: 20.6 µg/m³, 1.7× usual New Taipei City, 17 February: 36.0 µg/m³, 2.9× usual New Taipei City, 18 February: 10.5 µg/m³, 0.9× usual New Taipei City, 19 February: 8.7 µg/m³, 0.7× usual New Taipei City, 20 February: 9.9 µg/m³, 0.8× usual Neili Neili, 14 February: 9.0 µg/m³, 0.6× usual Neili, 15 February: 26.9 µg/m³, 1.8× usual Neili, 16 February: 25.3 µg/m³, 1.7× usual Neili, 17 February: 36.0 µg/m³, 2.4× usual Neili, 18 February: 12.1 µg/m³, 0.8× usual Neili, 19 February: 8.2 µg/m³, 0.5× usual Neili, 20 February: 13.5 µg/m³, 0.9× usual Zhubei Zhubei, 14 February: 7.8 µg/m³, 0.6× usual Zhubei, 15 February: 25.1 µg/m³, 2.0× usual Zhubei, 16 February: 25.3 µg/m³, 2.0× usual Zhubei, 17 February: 34.8 µg/m³, 2.7× usual Zhubei, 18 February: 10.3 µg/m³, 0.8× usual Zhubei, 19 February: 6.6 µg/m³, 0.5× usual Zhubei, 20 February: 13.7 µg/m³, 1.1× usual Taoyuan Taoyuan, 14 February: 6.6 µg/m³, 0.6× usual Taoyuan, 15 February: 22.1 µg/m³, 1.9× usual Taoyuan, 16 February: 21.5 µg/m³, 1.8× usual Taoyuan, 17 February: 33.5 µg/m³, 2.9× usual Taoyuan, 18 February: 10.8 µg/m³, 0.9× usual Taoyuan, 19 February: 8.4 µg/m³, 0.7× usual Taoyuan, 20 February: 10.9 µg/m³, 0.9× usual Changhua Changhua, 14 February: 9.8 µg/m³, 0.6× usual Changhua, 15 February: 19.1 µg/m³, 1.2× usual Changhua, 16 February: 23.3 µg/m³, 1.5× usual Changhua, 17 February: 33.5 µg/m³, 2.2× usual Changhua, 18 February: 20.7 µg/m³, 1.3× usual Changhua, 19 February: 12.3 µg/m³, 0.8× usual Changhua, 20 February: 15.8 µg/m³, 1.0× usual Sanzhi Sanzhi, 14 February: 0.5 µg/m³, 0.1× usual Sanzhi, 15 February: 2.7 µg/m³, 0.5× usual Sanzhi, 16 February: 6.8 µg/m³, 1.3× usual Sanzhi, 17 February: 33.3 µg/m³, 6.2× usual Sanzhi, 18 February: 0.8 µg/m³, 0.1× usual Sanzhi, 19 February: 1.5 µg/m³, 0.3× usual Sanzhi, 20 February: 2.9 µg/m³, 0.5× usual Shulin Shulin, 14 February: 5.5 µg/m³, 0.4× usual Shulin, 15 February: 20.5 µg/m³, 1.6× usual Shulin, 16 February: 24.5 µg/m³, 1.9× usual Shulin, 17 February: 33.1 µg/m³, 2.6× usual Shulin, 18 February: 12.6 µg/m³, 1.0× usual Shulin, 19 February: 6.5 µg/m³, 0.5× usual Shulin, 20 February: 8.4 µg/m³, 0.7× usual Hsinchu Hsinchu, 14 February: 15.1 µg/m³, 1.1× usual Hsinchu, 15 February: 27.9 µg/m³, 2.0× usual Hsinchu, 16 February: 24.5 µg/m³, 1.7× usual Hsinchu, 17 February: 30.6 µg/m³, 2.2× usual Hsinchu, 18 February: 11.9 µg/m³, 0.8× usual Hsinchu, 19 February: 6.9 µg/m³, 0.5× usual Hsinchu, 20 February: 16.5 µg/m³, 1.2× usual Daxi Daxi, 14 February: 6.3 µg/m³, 0.5× usual Daxi, 15 February: 23.3 µg/m³, 1.7× usual Daxi, 16 February: 24.9 µg/m³, 1.8× usual Daxi, 17 February: 30.0 µg/m³, 2.1× usual Daxi, 18 February: 12.0 µg/m³, 0.9× usual Daxi, 19 February: 6.6 µg/m³, 0.5× usual Daxi, 20 February: 14.4 µg/m³, 1.0× usual Yilan Yilan, 14 February: 3.9 µg/m³, 0.5× usual Yilan, 15 February: 4.1 µg/m³, 0.5× usual Yilan, 16 February: 13.0 µg/m³, 1.5× usual Yilan, 17 February: 29.4 µg/m³, 3.4× usual Yilan, 18 February: 14.8 µg/m³, 1.7× usual Yilan, 19 February: 7.5 µg/m³, 0.9× usual Yilan, 20 February: 8.1 µg/m³, 0.9× usual 14 Feb 15 16 17 18 19 20 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. Good 0–50
Moderate 51–100
Sensitive groups 101–150
Unhealthy 151–200
Very unhealthy 201–300
Hazardous 301+
Every city it reached
City Days Highest Usual Above usual
Sanzhi Taipei, Taiwan 1 17 February 5.4 6.2× Yilan Taiwan 1 17 February 8.6 3.4× Keelung Taiwan 1 17 February 11.9 3.1× Xizhi Taipei, Taiwan 1 17 February 12.7 3.0× New Taipei City Taipei, Taiwan 1 17 February 12.3 2.9× Taoyuan Taiwan 1 17 February 11.7 2.9× Taipei Taiwan 1 17 February 13.0 2.8× Magong Taiwan 1 17 February 13.8 2.8× Zhubei Taiwan 1 17 February 12.8 2.7× Shulin Taipei, Taiwan 1 17 February 12.9 2.6× Neili Taiwan 1 17 February 15.1 2.4× Xinying Taiwan 1 17 February 19.1 2.4× Toufen Taiwan 1 14 February 13.7 2.2× Changhua Taiwan 1 17 February 15.4 2.2× Hsinchu Taiwan 1 17 February 14.2 2.2× Daxi Taiwan 1 17 February 14.0 2.1× Erlun Taiwan 1 17 February 19.9 2.1× Beigang Taiwan 1 17 February 18.8 2.1× Chiayi City Taiwan 1 17 February 21.8 2.1× Erlin Taiwan 1 17 February 18.4 2.1× Jincheng Fukien, Taiwan 1 17 February 22.9 2.1×
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 Taiwan
Number 3 of 8 episodes in Taiwan since our records began, by cities reached.
Bars: cities reached; colour: the level of the episode's highest daily reading.
Use this page SmogRank, Taiwan, February 2025: 21 cities with PM2.5 at twice their usual or more, 17 February 2025, smogrank.com/episodes/2025-02-taiwan (accessed 2 October 2026).
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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.
