2019 美国 AQI平均值
PM2.5浓度 2019年韩国达到2倍以上 世界卫生组织污染暴露建议值
|2019 韩国污染最严重的城市||Jeungpyeong, Chungcheongbuk-do|
Officially known as the Republic of Korea, South Korea is a Southeast Asian country located on the southern part of the Korean peninsula. The northern part being occupied by North Korea with which it shares a land border. In 2019, the country had a population of around 50 million people, out of which, half live in the capital city of Seoul.
At the end of 2020, Seoul was experiencing “Good” air quality with a US AQI figure of 41. This is based on recommendations from the World Health Organisation (WHO). The main pollutants suspended in the air constituted of: - PM2.5 - 10 µg/m³, PM10 - 26.5 µg/m³, ozone (O3) - 22 µg/m³, nitrogen dioxide (NO2) - 52.6 µg/m³, sulphur dioxide (SO2) - 7.9 µg/m³ and carbon monoxide (CO) - 572.5 µg/m³. With figures like these windows and doors can be safely opened and outdoor activities enjoyed.
In 2019, the annual average air quality in South Korea was classified as being "Moderate" with a reading of 78 US AQI. The PM2.5 level was twice the recommended level. In world rankings, South Korea was listed as being the 26th dirtiest country out of 98 which were judged.
During the winter and spring of 2019, the Korean Peninsula was engulfed in the worst type of fine dust. From January to March, 12 emergency measures to reduce fine dust were imposed but only in the metropolitan area. In March, for the first time ever, they were issued for 7 consecutive days. At this time, the daily average concentration of ultrafine dust (PM2.5) in Seoul was 129 μg per m³ (micrograms per cubic metre). In 2020, due to the fine dust seasonal management system the average concentration per cubic metre in Korea for four months has decreased by 27 per cent from 33 μg last year to 24 μg this year. Experts who look for reasons why this should be attributed it to the reduction in movement due to the COVID 19 pandemic, social activities ceased, factories were shut down and traffic dramatically decreased.
In 2019, the average concentration of ultrafine dust (PM2.5) in South Korea was the worst among the member countries of the Organisation for Economic Cooperation and Development (OECD). It was second place in 2018, but it climbed one step to the top. According to the '2019 World Air Quality Report' released this month by AirVisual, a global air pollution investigation agency, South Korea's annual average ultrafine dust concentration last year was 24.8 µg/m³ which was the worst among OECD member countries. Chile (24.9 µg/m³), which had the highest concentration of ultrafine dust among OECD countries in 2018, recorded 22.6 µg/m³ last year, improving the concentration of fine dust compared to Seoul
There are two main sources of air pollution in South Korea, namely emissions from burning fossil fuels and vehicle emissions. In 1960, South Korea was a developing country switching from an agrarian to an industrial economy. During the 1980s and 90s, South Korea’s economy grew at a rate of 10 per cent per annum. In 2015 South Korea was ranked as the world’s 11th largest gross domestic producer but this position was attained through dirty coal-fired power stations and dirty vehicle emissions.
A large percentage of the pollutants are blown in by the prevailing winds from China. It is thought that between 30 and 50 per cent of PM2.5 pollutant in South Korea, originated from China. These are figures recorded on “good” days on “bad” days it can reach as high as 60 to 80 per cent. During the colder winter months, the air currents are noticeably slower and therefore do not disperse the pollutants that still drift across from China. South Korea too must shoulder some of the blame with its heavy reliance on coal-fired power stations and diesel fumes from vehicles and generators.
Due to China’s rapidly developing economy, it burns an estimated 4 billion tons of coal to feed its power-hungry population. This contributes to at least 50 per cent of the PM2.5 particulates suspended in South Korea’s air. The situation is exacerbated by the dust blown in from China’s western deserts and Inner Mongolia. The mega-city of Shanghai was also to blame as a source of pollution. This situation is expected to worsen as China continues to satisfy its need for energy unless steps are taken to prevent it.
When data from domestic and overseas satellite observations such as the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) are combined and analysed, the levels of sulphur dioxide (SO2) has decreased significantly since the 1990s. This is partially due to the regulation on the use of solid fuels such as anthracite. The high proportion of low sulphur oil and the introduction of liquefied natural gas (LNG) is also substantial. The same can be said of nitrogen dioxide (NO₂), which is often produced from the exhaust gases from vehicles. The concentration of nitrogen dioxide had slowly increased but has been gradually decreasing since 2007. The number of cars continued to increase, but the reduction in nitrogen dioxide means that emission regulations have become stronger.
When it comes to levels of sulphur dioxide (SO2) and nitrogen dioxide (NO2), both China and Japan are getting lower. Looking at the concentration trend from 2011 to 2018, both sulphur dioxide and nitrogen dioxide in China are significantly decreasing. However, it should be taken into account that this is a relative value. This means that China's emissions decreased significantly in 2018 compared to 2011, but it will still be higher than that of South Korea and Japan. What is impressive is Japan, where there is already a lower level of air pollutant emissions than South Korea and China. Nevertheless, pollutant emissions decreased in 2018 compared to 2011. With a concerted effort, these levels could drop further.
Many different types of pollution have increased proportionately as South Korea’s economy has increased over the last decades. Satellite data from the National Aeronautics and Space Administration (NASA) satellite has shown that Seoul is amongst one of the world’s cities with the worst air pollution. Between 2009 and 2013 the average PM10 figures were considerably higher than of capital cities such as London, Paris, Tokyo and Los Angeles. Because of this poor air quality, it is estimated that 16 per cent of all deaths recorded in Seoul are due to air pollution.
At the end of 2020, the South Korean city of Jeungpyeong took the title of the dirtiest city with a US AQI reading of 97. This classed it as “Moderate” but the 2 previous days had classed it as being "Unhealthy".
With levels of this scale, it is advisable to close doors and windows to stop the ingress of dirty air and the group of people who are sensitive to poor air quality should consider staying indoors if possible or to use a good quality mask if venturing outside is inevitable.
In comparison to other cities, the average annual concentration of ultrafine dust in Jeungpyeong-gun, Chungbuk, was 33.9 µg/m³, which was the worst in South Korea. The average concentration of Jeungpyeong-gun was ranked 7th among the top 100 cities in OECD countries. In addition, 61 out of the top 100 cities with the most severe dust pollution among all OECD member countries are Korean cities. In 2018, 44 of the top 100 cities increased by 1.6 times compared to that of Korean cities. In the report, it was stated that no city in Korea has been able to meet the annual average PM2.5 concentration of 10 µg/m³ as recommended by the World Health Organisation (WHO). Most of the air pollution-related policies of the South Korean government focus only on temporary policies and diesel emissions reduction.
The air pollution problem is a global concern, in the past, air pollution has been looked on as a local problem. The size of the pollutant source was small and the population density was low. But now both of these factors have increased and it has become not only a national problem but a global one too. Satellite observation is of great help in monitoring air pollutants crossing borders. It was also an opportunity to confirm that social change can reduce air pollutants.
In February 2020, Korea successfully launched the Cheonrian 2B satellite. The satellite eventually settled in geostationary orbit 36,000 km above the Korean Peninsula. The satellite is equipped with an environmental satellite which incorporates a sensor that tracks pollutants in the air. From the beginning of next year, air pollutants such as nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) from 26 countries in East Asia including Korea will be observed and tracked eight times a day.
Ground monitoring systems can accurately determine the properties and concentrations of pollutants in certain areas. In order to track pollutants entering the country from outside, observation networks must be located above the sea. It is not easy to reliably measure air quality on the sea. Having North Korea as a neighbour has its ramifications because the impact of pollutants exchanged with North Korea is quite significant, but there is no data on measuring air pollutants in North Korea. The use of satellites fills that void. The earth can be seen from above without borders and the occurrence, movement, and distribution of pollutants can be easily observed.
Since 2016, the Korean Ministry of Environment has regulated 11 different air pollutants and categorised a further 32 as being hazardous to health. It is their intention to close down 10 of their 61 coal-fired power stations by 2025.
Fossil fuel combustion is the largest contributor to air pollution than anything else in South Korea. The country itself has very little natural resources and therefore imports all but 1 per cent of all its needs. The country heavily relies on this source of energy for its increasing demand in expanding industries. 38 per cent of Korea’s energy requirements come from oil, with a further 29 per cent from coal and a relatively low reliance on gas at just 15 per cent.
The number of cars and other vehicles on Korea’s roads is increasing rapidly. Due to the expanding economy, more delivery vehicles are used in the cities and these are usually powered by diesel which is a particularly dirty fuel when used in heavy-duty vehicles.
An efficient public transport system is needed to encourage people to leave their cars at home and commute on public transport. Modern buses can be powered by clean sustainable energy and electricity. Many trains run on electricity too. Delivery vehicles when used within the city limits could be restricted to electric power only.
Strong, healthy people with no known pre-existing medical conditions can be affected by air pollution. The effects may be mild symptoms of coughing and wheezing or irritated eyes. Skin irritations can happen too depending on the specific pollutants suspended in the air.
These symptoms become severe for certain groups of people such as pregnant women, children under the age of 14 years and senior citizens. They may soon succumb to aggravated cardiovascular and respiratory illnesses, shortage of breath due to stress placed on the heart and lungs as they work harder to maintain the required level of oxygen needed by the body. Cells in the respiratory organs can become irrevocably damaged in a relatively short span of time.
People in these groups may suffer from health problem at lower air pollution exposure levels, or their health may be affected more intensely.
Prolonged exposure may lead to the faster ageing of the lung tissue which leads to a loss in capacity and thus functionality. Diseases such as asthma, bronchitis, emphysema, and possibly cancer are more prevalent in heavily polluted cities.