Air pollution in Taiwan
Air pollution in Taiwan is mostly derived from sources of domestic combustion, primarily the burning of fossil fuels. Taiwan's topography has been noted to be a contributing factor to its air pollution problem, leading to poor dispersal and trapping pollutants. Taipei, Taiwan's capital and largest city for example, is surrounded by mountains, and other industrial centers along the northern and western coasts of Taiwan are surrounded by high mountains. Types of pollutants PM10 In March 2014, Taiwanese legislators and the Taiwan Healthy Air Action Alliance claimed, based on reports by the World Health Organization, that the air quality in Taiwan was the worst out of the Four Asian Tigers. Attention was mainly drawn to the annual mean PM10 level of Taiwan's air (54 micrograms per cubic meter). This annual mean of Taipei (47.1 micrograms per cubic meter), made the city rank 1,089 out of 1,600 when compared to the air quality of other cities around the world. Based on 2004 data by Taiwan's Department of Environmental Protection, the annual mean PM10 level for Taiwan had, for the last decade, been worse than the European Union limit value (40 micrograms per cubic meter) every year. Fugitive dust In the winter of 2013-2014, the Environmental Protection Administration's (EPA) Department of Environmental Monitoring and Information Management, examined the air pollution of the country. It was revealed that stations in Yunlin, Chiayi and Greater Tainan, had the worst pollution concentrations. According to the EPA Department's Deputy Director, Chang Shuenn-chin (張順欽), this pollution is primarily caused by fugitive dust found at the riverbanks during the low-flow season of winter. These particles — suspended in the air by wind action and human activities — can be stirred up by the strong northeastern winds occurring in winter. This is also known as the northeastern monsoon. Therefore, wind speeds exceeding three meters per second are likely to cause gusts of fugitive dust with PM10 concentration levels above 250μg/m3. High maximum readings in PM10 concentration levels in Yunlin County's Lunbei Township (崙背) in 2015 (2,532μg/m3) and in Chiayi County's Puzih City (朴子) in 2009 (1,793μg/m3) and; in 2013; in Puzih (497μg/m3) and in Lunbei (497μg/m3) are claimed to be heavily influenced by heavy rainfall and mudslides during Typhoon Morakot in 2009 as well as by the 6.2 Mw June 2013 Nantou earthquake. Earthquakes can shake up loose soil on upstream slope areas. This can later be washed downstream by torrential rains during the summer thereby increasing the likelihood for land collapse and mud slides, which in turn creates dust on riverbanks. PM2.5 With regards to research conducted on PM2.5 particles in Taiwan, the National Taiwan University in March 2015 claimed that traffic is the major source of air pollutants in Taipei. In central Taiwan, on the other hand, fine particles are primarily produced by thermal power plants. While presenting this research, the National Taiwan University stated that the annual mean concentration of PM2.5 particles in Taipei City and New Taipei City is 20 µg/m3, while being 30 µg/m3 in