SmogRank / Episodes / Taiwan
Taiwan, May 2024
For 3 days, from 18 to 20 May 2024, 16 cities in Taiwan had PM2.5 at least twice their usual for the time of year. The worst reading was Tainan, Taiwan: 40.4 µg/m³ on 20 May, about 3.5× its usual 11.4.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 16 in 1 country
Days 3 18 to 20 May 2024
Worst day 19 May 14 cities counted
Furthest above usual 3.5× Tainan
Day by day
Play 19 May 14 cities at twice their usual or more
Erlin Changhua Taitung Buzi Xizhou Magong Hualien City Miaoli Hengchun Toufen Zhudong Hsinchu Zhubei Daxi Neili Taoyuan Yilan Shulin New Taipei City Taipei Xizhi Sanzhi Keelung Jincheng Ishigaki Zhushan Erlun Nantou Taichung Puli Taibao Douliu Chiayi City Yuanlin Beigang Xinying Fengshan Kaohsiung Chaozhou Yongkang Tainan 15 May 16 17 18 19 20 21 22 23 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
Zhushan Zhushan, 15 May: 29.8 µg/m³, 2.3× usual Zhushan, 16 May: 25.3 µg/m³, 1.9× usual Zhushan, 17 May: 25.5 µg/m³, 1.9× usual Zhushan, 18 May: 26.4 µg/m³, 2.0× usual Zhushan, 19 May: 24.5 µg/m³, 1.9× usual Zhushan, 20 May: 24.0 µg/m³, 1.8× usual Zhushan, 21 May: 15.3 µg/m³, 1.2× usual Zhushan, 22 May: 11.5 µg/m³, 0.9× usual Zhushan, 23 May: 13.5 µg/m³, 1.0× usual Yongkang Yongkang, 15 May: 25.8 µg/m³, 2.2× usual Yongkang, 16 May: 24.5 µg/m³, 2.0× usual Yongkang, 17 May: 20.6 µg/m³, 1.7× usual Yongkang, 18 May: 27.7 µg/m³, 2.3× usual Yongkang, 19 May: 30.5 µg/m³, 2.5× usual Yongkang, 20 May: 37.6 µg/m³, 3.1× usual Yongkang, 21 May: 16.8 µg/m³, 1.4× usual Yongkang, 22 May: 19.6 µg/m³, 1.6× usual Yongkang, 23 May: 18.6 µg/m³, 1.6× usual Tainan Tainan, 15 May: 24.7 µg/m³, 2.2× usual Tainan, 16 May: 23.7 µg/m³, 2.1× usual Tainan, 17 May: 19.1 µg/m³, 1.7× usual Tainan, 18 May: 27.7 µg/m³, 2.4× usual Tainan, 19 May: 28.7 µg/m³, 2.5× usual Tainan, 20 May: 40.4 µg/m³, 3.5× usual Tainan, 21 May: 17.6 µg/m³, 1.5× usual Tainan, 22 May: 22.7 µg/m³, 2.0× usual Tainan, 23 May: 20.3 µg/m³, 1.8× usual Chaozhou Chaozhou, 15 May: 13.8 µg/m³, 1.5× usual Chaozhou, 16 May: 21.4 µg/m³, 2.3× usual Chaozhou, 17 May: 23.2 µg/m³, 2.5× usual Chaozhou, 18 May: 26.9 µg/m³, 2.9× usual Chaozhou, 19 May: 26.5 µg/m³, 2.9× usual Chaozhou, 20 May: 28.9 µg/m³, 3.1× usual Chaozhou, 21 May: 8.5 µg/m³, 0.9× usual Chaozhou, 22 May: 13.8 µg/m³, 1.5× usual Chaozhou, 23 May: 12.7 µg/m³, 1.4× usual Beigang Beigang, 15 May: 20.8 µg/m³, 1.7× usual Beigang, 16 May: 20.7 µg/m³, 1.7× usual Beigang, 17 May: 20.2 µg/m³, 1.6× usual Beigang, 18 May: 26.4 µg/m³, 2.1× usual Beigang, 19 May: 31.6 µg/m³, 2.6× usual Beigang, 20 May: 26.6 µg/m³, 2.2× usual Beigang, 21 May: 22.0 µg/m³, 1.8× usual Beigang, 22 May: 19.7 µg/m³, 1.6× usual Beigang, 23 May: 22.7 µg/m³, 1.8× usual Chiayi City Chiayi City, 15 May: 23.1 µg/m³, 2.0× usual Chiayi City, 16 May: 23.4 µg/m³, 2.0× usual Chiayi City, 17 May: 18.9 µg/m³, 1.6× usual Chiayi City, 18 May: 25.4 µg/m³, 2.2× usual Chiayi City, 19 May: 28.3 µg/m³, 2.4× usual Chiayi City, 20 May: 28.0 µg/m³, 2.4× usual Chiayi City, 21 May: 16.3 µg/m³, 1.4× usual Chiayi City, 22 May: 16.8 µg/m³, 1.4× usual Chiayi City, 23 May: 14.4 µg/m³, 1.2× usual Yuanlin Yuanlin, 15 May: 19.3 µg/m³, 1.4× usual Yuanlin, 16 May: 19.9 µg/m³, 1.5× usual Yuanlin, 17 May: 24.0 µg/m³, 1.8× usual Yuanlin, 18 May: 23.6 µg/m³, 1.7× usual Yuanlin, 19 May: 34.8 µg/m³, 2.6× usual Yuanlin, 20 May: 29.8 µg/m³, 2.2× usual Yuanlin, 21 May: 26.0 µg/m³, 1.9× usual Yuanlin, 22 May: 17.7 µg/m³, 1.3× usual Yuanlin, 23 May: 19.1 µg/m³, 1.4× usual Douliu Douliu, 15 May: 23.0 µg/m³, 1.7× usual Douliu, 16 May: 23.4 µg/m³, 1.7× usual Douliu, 17 May: 23.7 µg/m³, 1.8× usual Douliu, 18 May: 25.9 µg/m³, 1.9× usual Douliu, 19 May: 32.1 µg/m³, 2.4× usual Douliu, 20 May: 23.4 µg/m³, 1.7× usual Douliu, 21 May: 15.5 µg/m³, 1.1× usual Douliu, 22 May: 11.6 µg/m³, 0.9× usual Douliu, 23 May: 13.8 µg/m³, 1.0× usual Xinying Xinying, 15 May: 17.5 µg/m³, 1.7× usual Xinying, 16 May: 17.9 µg/m³, 1.7× usual Xinying, 17 May: 14.7 µg/m³, 1.4× usual Xinying, 18 May: 22.0 µg/m³, 2.1× usual Xinying, 19 May: 29.1 µg/m³, 2.8× usual Xinying, 20 May: 27.7 µg/m³, 2.6× usual Xinying, 21 May: 15.5 µg/m³, 1.5× usual Xinying, 22 May: 16.5 µg/m³, 1.6× usual Xinying, 23 May: 17.7 µg/m³, 1.7× usual Erlun Erlun, 15 May: 18.7 µg/m³, 1.4× usual Erlun, 16 May: 21.1 µg/m³, 1.5× usual Erlun, 17 May: 19.2 µg/m³, 1.4× usual Erlun, 18 May: 26.5 µg/m³, 1.9× usual Erlun, 19 May: 28.8 µg/m³, 2.1× usual Erlun, 20 May: 20.7 µg/m³, 1.5× usual Erlun, 21 May: 26.0 µg/m³, 1.9× usual Erlun, 22 May: 18.3 µg/m³, 1.3× usual Erlun, 23 May: 22.3 µg/m³, 1.6× usual Taibao Taibao, 15 May: 19.5 µg/m³, 1.7× usual Taibao, 16 May: 19.6 µg/m³, 1.7× usual Taibao, 17 May: 16.8 µg/m³, 1.4× usual Taibao, 18 May: 24.0 µg/m³, 2.1× usual Taibao, 19 May: 28.2 µg/m³, 2.4× usual Taibao, 20 May: 20.8 µg/m³, 1.8× usual Taibao, 21 May: 19.3 µg/m³, 1.6× usual Taibao, 22 May: 20.8 µg/m³, 1.8× usual Taibao, 23 May: 22.8 µg/m³, 1.9× usual Fengshan Fengshan, 15 May: 19.4 µg/m³, 1.5× usual Fengshan, 16 May: 23.2 µg/m³, 1.8× usual Fengshan, 17 May: 23.9 µg/m³, 1.9× usual Fengshan, 18 May: 24.7 µg/m³, 1.9× usual Fengshan, 19 May: 26.5 µg/m³, 2.1× usual Fengshan, 20 May: 38.8 µg/m³, 3.0× usual Fengshan, 21 May: 17.6 µg/m³, 1.4× usual Fengshan, 22 May: 18.6 µg/m³, 1.5× usual Fengshan, 23 May: 15.6 µg/m³, 1.2× usual Taichung Taichung, 15 May: 14.3 µg/m³, 1.3× usual Taichung, 16 May: 16.6 µg/m³, 1.5× usual Taichung, 17 May: 19.5 µg/m³, 1.7× usual Taichung, 18 May: 19.3 µg/m³, 1.7× usual Taichung, 19 May: 26.1 µg/m³, 2.3× usual Taichung, 20 May: 23.4 µg/m³, 2.1× usual Taichung, 21 May: 20.9 µg/m³, 1.8× usual Taichung, 22 May: 10.6 µg/m³, 0.9× usual Taichung, 23 May: 12.8 µg/m³, 1.1× usual Nantou Nantou, 15 May: 21.1 µg/m³, 1.8× usual Nantou, 16 May: 18.4 µg/m³, 1.6× usual Nantou, 17 May: 19.6 µg/m³, 1.7× usual Nantou, 18 May: 21.8 µg/m³, 1.8× usual Nantou, 19 May: 25.9 µg/m³, 2.2× usual Nantou, 20 May: 21.5 µg/m³, 1.8× usual Nantou, 21 May: 15.7 µg/m³, 1.3× usual Nantou, 22 May: 9.0 µg/m³, 0.8× usual Nantou, 23 May: 10.0 µg/m³, 0.8× usual Puli Puli, 15 May: 23.7 µg/m³, 2.3× usual Puli, 16 May: 22.0 µg/m³, 2.1× usual Puli, 17 May: 22.5 µg/m³, 2.2× usual Puli, 18 May: 19.6 µg/m³, 1.9× usual Puli, 19 May: 25.0 µg/m³, 2.4× usual Puli, 20 May: 23.5 µg/m³, 2.3× usual Puli, 21 May: 18.3 µg/m³, 1.8× usual Puli, 22 May: 8.2 µg/m³, 0.8× usual Puli, 23 May: 7.4 µg/m³, 0.7× usual Kaohsiung Kaohsiung, 15 May: 20.2 µg/m³, 2.0× usual Kaohsiung, 16 May: 22.0 µg/m³, 2.2× usual Kaohsiung, 17 May: 21.9 µg/m³, 2.1× usual Kaohsiung, 18 May: 24.6 µg/m³, 2.4× usual Kaohsiung, 19 May: 22.8 µg/m³, 2.2× usual Kaohsiung, 20 May: 31.6 µg/m³, 3.1× usual Kaohsiung, 21 May: 13.8 µg/m³, 1.4× usual Kaohsiung, 22 May: 14.4 µg/m³, 1.4× usual Kaohsiung, 23 May: 14.2 µg/m³, 1.4× usual 15 May 16 17 18 19 20 21 22 23 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
Tainan Taiwan 3 20 May 11.4 3.5× Chaozhou Taiwan 3 20 May 9.2 3.1× Yongkang Taiwan 3 20 May 12.0 3.1× Kaohsiung Takao, Taiwan 1 20 May 10.2 3.1× Fengshan Takao, Taiwan 2 20 May 12.8 3.0× Xinying Taiwan 2 19 May 10.5 2.8× Yuanlin Taiwan 2 19 May 13.5 2.6× Beigang Taiwan 3 19 May 12.3 2.6× Puli Taiwan 1 19 May 10.3 2.4× Chiayi City Taiwan 3 19 May 11.7 2.4× Taibao Taiwan 1 19 May 11.7 2.4× Douliu Taiwan 1 19 May 13.5 2.4× Taichung Taiwan 1 19 May 11.3 2.3× Zhushan Taiwan 1 15 May 13.2 2.3× Nantou Taiwan 1 19 May 11.8 2.2× Erlun Taiwan 1 19 May 13.7 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 8 of 12 episodes in Taiwan since our records began, by cities reached.
Taiwan, February 2025 24 Taiwan, January 2025 22 Taiwan, February 2025 21 Taiwan, November 2024 21 Taiwan, March 2024 20 Taiwan, December 2024 18 Taiwan, November 2025 17 Taiwan, May 2024 16 Taiwan, January 2025 14 Taiwan, February 2026 13 Taiwan, March 2025 13 Taiwan, November 2025 12 Bars: cities reached; colour: the level of the episode's highest daily reading.
Use this page SmogRank, Taiwan, May 2024: 16 cities with PM2.5 at twice their usual or more, 18 to 20 May 2024, smogrank.com/episodes/2024-05-taiwan (accessed 3 October 2026).
Copy citation 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.
