Taiwan's Air Pollution: Causes And Concerns

Taiwan, an island nation off the east coast of China, faces significant air pollution issues, particularly in its metropolitan cities. Various factors contribute to this problem, including domestic combustion, primarily the burning of fossil fuels, and urbanization. Natural factors, such as wind patterns, earthquakes, and typhoons, also play a role in dispersing or exacerbating pollutants. According to the Taiwan Environmental Protection Administration (TEPA), air quality in urban areas is much poorer than in rural areas. The capital, Taipei, has been ranked poorly in global comparisons, with traffic and dust pollution identified as major sources of air pollutants.

Domestic combustion and fossil fuels

Air pollution in Taiwan is largely caused by domestic combustion, with the burning of fossil fuels being a primary source. Taiwan's topography, with its capital Taipei and other industrial centres surrounded by mountains, also contributes to poor dispersal and the trapping of pollutants.

Taiwan's energy consumption is high, with an equivalent of 10.5 million kiloliters of oil, or about 2.2 million barrels a day. Consumption of petroleum products alone accounts for about half of Taiwan's energy supply, equivalent to 4.5 million kiloliters of oil. In 2022, 79.6% of Taiwan's electricity generation came from fossil fuels, with natural gas, coal, and oil being the most significant sources. The country's heavy reliance on imported fossil fuels, particularly from the Middle East, poses energy security risks and makes Taiwan vulnerable to external disruptions.

The burning of fossil fuels releases various pollutants into the atmosphere, contributing to Taiwan's air quality issues. These pollutants can include particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), and sulfur oxides. For example, the Tunghsiao Power Plant in central Taiwan previously contributed to high levels of sulfur oxides, but a shift to gas-fired electricity led to a 99% reduction in these emissions by 2010.

To address the air pollution caused by domestic combustion and fossil fuels, Taiwan has taken steps to reduce its dependence on imported oil and increase the use of renewable energy sources. The government aims for renewable energy to account for 15% of the nation's energy by 2025, with investments in solar energy, wind power, and other sustainable technologies. Additionally, Taiwan has one active nuclear reactor, the Maanshan Nuclear Power Plant, which provided 16% of overall generation in 2015.

While efforts are being made to transition to cleaner energy sources, domestic combustion and fossil fuel usage continue to be significant contributors to air pollution in Taiwan. The country's high energy consumption, reliance on imports, and geographical factors all play a role in the persistence of this issue.

Topography and poor dispersal

Taiwan's topography has been identified as a contributing factor to its poor air quality, trapping pollutants and causing poor dispersal. The nation's capital and largest city, Taipei, is surrounded by mountains, as are other industrial centres along the northern and western coasts. This unique geography prevents the dispersal of air pollutants, leading to a build-up of harmful substances in the atmosphere.

The impact of topography on air quality is evident in the concentration of PM2.5 and PM10 particles, which are used to measure air pollution levels. In 2014, the annual mean PM10 level in Taiwan was 54 micrograms per cubic meter, with Taipei's level at 47.1 micrograms per cubic meter. This data highlights the significant influence of geographical factors on air pollution levels in Taiwan.

The concentration of these particles is particularly high at ground level and up to three-story heights in urban areas, with levels of hazardous particles such as silicon and iron decreasing with increasing altitude. This phenomenon is attributed to dust and traffic pollution, which are more concentrated at lower levels. The impact of traffic pollution is further supported by research from National Taiwan University, which identified traffic as the primary source of air pollutants in Taipei.

In addition to geographical factors, weather conditions also play a role in the dispersal of air pollutants in Taiwan. Strong winds from China can carry air pollutants across the strait, significantly impacting Taiwan's air quality during the winter months. Natural disasters, such as the 2009 Typhoon Morakot, can also contribute to poor air quality by causing mudslides and washing loose soil downstream, increasing the likelihood of land collapse and creating dust on riverbanks.

Traffic and dust pollution

Air pollution in Taiwan is largely caused by traffic and dust pollution. In 2015, research from National Taiwan University found that traffic is the primary source of air pollutants in Taipei, with similar findings for New Taipei City and Kaohsiung. The annual average of PM2.5 particles in Taipei City was 20 μg/m3, 30 μg/m3 in Kaohsiung, and 20 μg/m3 in New Taipei City. These figures exceed the acceptable limit of 15 μg/m3, which is three times higher than the limit in the USA and five times higher than the World Health Organization's recommended level.

Traffic pollution is not limited to ground-level emissions. In Taipei, it was found that the concentration of hazardous particles such as silicon and iron decreased with increasing altitude. This indicates that pollution from traffic and other sources is trapped at lower altitudes, affecting the air quality that people breathe.

Urbanization and weather conditions also play a role in Taiwan's air pollution. The island's topography, with cities surrounded by mountains, traps pollutants and prevents their dispersal. Additionally, strong winds can carry air pollutants from China, negatively impacting Taiwan's air quality, especially during the winter months.

Dust pollution is another significant contributor to Taiwan's air quality issues. Natural disasters such as typhoons, earthquakes, and mudslides can dislodge soil, which is then washed downstream by heavy rainfall. This soil dries up on riverbanks, creating dust that contributes to air pollution. Human activity, such as construction, can also generate dust, further adding to the problem.

Industrial centres and urbanisation

Taiwan's air pollution is largely attributed to domestic combustion, particularly the burning of fossil fuels. The country's topography, with its industrial centres surrounded by mountains, traps pollutants and impedes their dispersal. Urbanisation and industrial activities have significantly contributed to air pollution in metropolitan areas.

Taipei, the country's capital and largest city, exemplifies the impact of urbanisation on air quality. Surrounded by mountains, Taipei's geographical layout traps air pollutants, leading to higher concentrations in the lower atmosphere. Extensive studies conducted in Taipei between 1993 and 2012 revealed significantly higher levels of pollution in urban centres compared to rural areas, underscoring the role of urbanisation in exacerbating air quality issues.

The impact of industrial centres and urbanisation on air pollution is evident in the varying concentrations of particulate matter at different altitudes. Research by National Taiwan University found that the outdoor PM2.5 concentration at ground level up to three-story heights was ten to twenty times higher than that above four-story buildings. This indicates that industrial activities and ground-level traffic emissions significantly contribute to air pollution in Taiwan's urban centres.

In central Taiwan, the transition of the Tunghsiao Power Plant from coal to gas-fired electricity resulted in a dramatic decrease in sulfur oxide emissions. This success story demonstrates that implementing the right methods can effectively mitigate air pollution from industrial sources.

Additionally, weather conditions play a role in exacerbating air pollution in Taiwan's industrial centres and urban areas. Strong winds from China carry air pollutants across the Taiwan Strait, significantly deteriorating Taiwan's air quality during winter. Natural disasters, such as Typhoon Morakot in 2009, can also impact air quality by causing torrential rains that wash loose soil downstream, leading to increased dust and particulate matter.

Pollution from China

Taiwan's air quality is significantly impacted by air pollution from China, particularly during the winter months. Strong winds from China carry air pollutants that increase the levels of harmful particles in Taiwan's atmosphere. This cross-border haze, as it is known, can cause Taiwan's air quality to deteriorate to unhealthy and even hazardous levels. The Pollution Standards Index (PSI) readings during these periods often indicate elevated concentrations of major air pollutants such as PM10, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ground-level ozone.

The impact of China's air pollution on Taiwan is not limited to a single season. In March 2010, for example, a severe dust storm originating from China led to extremely high PM10 concentration levels in Taiwan. While smaller particles like PM2.5 may not travel as far, larger particles like PM10 can be carried over long distances. This means that while PM2.5 levels may not be significantly affected by Chinese pollution, PM10 levels certainly are.

In addition to seasonal variations, the topographical features of Taiwan also play a role in trapping pollutants. Cities like Taipei, the country's capital, are surrounded by mountains, which can hinder the dispersal of pollutants. This results in higher concentrations of harmful particles in the air, negatively affecting the air quality.

To address the issue of air pollution from China, Taiwan has taken several measures. The Taiwan Healthy Air Action Alliance, for instance, has worked to reduce emissions from state-owned enterprises, such as China Steel, Taipower, and the China National Petroleum Corporation. Additionally, the government has focused on reducing electricity usage, mitigating the greenhouse effect, and lowering indoor temperatures to decrease the demand for air conditioning. These efforts aim to improve Taiwan's air quality and protect the health of its citizens.

It is worth noting that Taiwan's own domestic combustion, urbanization, and industrial activities also contribute significantly to its air pollution. The burning of fossil fuels, particularly in thermal power plants, is a major source of pollution. However, Taiwan has made progress in reducing emissions, such as sulfur oxides, from these plants.

Frequently asked questions