TAIPEI (Taiwan News) -- Kaohsiung City was ranked as having the worst levels of PM2.5 air pollution out of all cities and counties in Taiwan last year, even though the city experienced a 24 decrease in unhealthy air alerts over the previous year, according to the Environmental Protection Administration (EPA).
From Jan. 1 to Dec. 25 of last year, the Air Quality Index (AQI) flashed 2,057 orange alerts for air that was "Unhealthy for Sensitive Groups," while 277 red alerts were issued for air that was "Unhealthy," for a total of 2,334 nationwide. However, this was an improvement of 706 fewer than the 3,040 orange and red alerts seen in 2017, at 2,671 and 369, respectively.
In terms of the ranking by cities and counties in Taiwan, Kaohsiung had the most unhealthy air alerts, with 702 orange alerts and 124 red alerts, for a total of 826. However, this represented a 24 percent decrease compared to the 1,075 unhealthy air alerts seen in 2017, which included 906 orange and 169 red alerts, respectively.
Last year, Tainan was ranked as having the second-worst air pollution, with 204 orange alerts and 32 red alerts, for a total of 236. Yunlin County came in third with 208 orange alerts and 23 red alerts, for a total of 231.
In fourth place was Changhua County, with 140 orange and red alerts, an increase of two over the previous year. Taichung rounded out the top five, with 122 unhealthy air alerts, however this was a decrease of 25 compared to the 147 alerts seen the previous year.
Although Taoyuan City saw six fewer unhealthy air alerts than the 118 reported the previous year, it still jumped up from eight to sixth place on the list. In seventh place was Nantou County, followed by Chiayi County, Pingtung County, and Miaoli County, rounding out the top 10.
Top 10 most polluted cities anc counties in Taiwan in 2018:
- Kaohsiung City
- Tainan City
- Yunlin County
- Changhua County
- Taichung City
- Taoyuan City
- Nantou County
- Chiayi County
- Pingtung County
- Miaoli County
As for greater Taipei, which had no red alerts in 2017, the EPA noted that the lantern festival on March 3 and other "folk activities" caused serious air pollution across western Taiwan, resulting in seven red alerts reported in New Taipei City and five in Taipei City.
Although most cities and counties in Taiwan issued fewer unhealthy air alerts, including Chiayi with a 36 percent reduction, other areas saw a deterioration in air quality. Miaoli saw the worst decline in air quality, with 74 orange alerts and 75 red alerts, as opposed to the 47 orange alerts and 27 red alerts seen in 2017, representing a 60 percent increase.
Hsinchu City also saw an increase from 16 orange alerts in 2017 to 26 in 2018, and one red alert. Changhua increased from 138 unhealthy air alerts to 140, with orange alerts increasing from 125 to 132, though the number of red alerts decreased from 13 to eight.
According to EPA, there are many possible factors which affected the increase and decrease of air pollution in Taiwan's cities and counties last year, such as meteorological conditions, including rainfall, winds, and high-pressure, which will require further analysis.