yeonggi-do, or more simply known as Gyeonggi, is a highly populated state and province located in South Korea, with its name translating to ‘the area surrounding the capital’, alluding to its proximity of the capital city, Seoul. Its provincial capital is the city of Suwon, the largest city in the whole state as well as a prominent tourist destination, also being home to some major multinational corporations such as Samsung electronics. The state is home to many major cities, all located within the northern region of South Korea. There are some less than appreciable levels of air pollution present across many of these cities, with some of them taking the top spot amongst Koreas most polluted, as well as having fairly high rankings out of all cities registered worldwide.
Gyeonggi is home to a sizeable amount of people, with over 25.5 million inhabitants living there, which is approximately just over half the total population of South Korea. Due to its northern location, it has some distinct disparity between its seasons, with extremes of cold being reached in the winter months, factors that all play a part in pollution readings during certain times of the year, something that will be discussed in further detail in following.
Looking at the air pollution readings taken across some of Gyeonggi's more prominent cities, ones such as Anseong and Yeoju stand out, and will be used as an example of Gyeonggi's pollution problems. Anseong came in with a yearly PM2.5 average of 31.6 μg/m³, a reading that would have placed it into the higher end of the ‘moderate’ ratings bracket, one that requires a PM2.5 reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such. As is shown with Anseong, it is only a few units away from breaching the measurement and moving up into the next grouping, with its high yearly reading (taken over 2019) placing Anseong into first place amongst all cities in Gyeonggi state, 3rd place out of all cities ranked in Korea, as well as 387th place out of all cities ranked worldwide.
These are distinctly less than optimal readings, with many of its months coming in much higher than its yearly average, as well as other cities across the state coming in with fairly similar readings, with Anseong at the top with its reading of 31.6 μg/m³ and the cleanest city in Gyeonggi still coming in at 21.8 μg/m³ (Yeoncheon city). This is indicative that Gyeonggi state is subject to some fairly bad levels of pollution.
Gyeonggi sees much of its pollution stemming from the same causes that afflict the whole of south Korea. It underwent a rapid industrialization and subsequent urbanization during the late 1900’s continuing through to the 2000’s and well into current times, seeing itself as a well-developed country with a strong infrastructure and economy. Despite this, it finds itself in the list of top 35 richest countries that are subject to poor air quality levels. Rapid industrialization with large amounts of aid from the United States (as well as other internal factors) lead to Korea becoming a significant manufacturing force, as well as a prominent exporter of goods on the world stage. All of these factors, whilst aiding in the growth of its economy alongside the overall quality of life in the country, unfortunately lead to pollution sources due to massive anthropogenic activity and movement and the subsequent pollutive fallout.
One of these main causes that would be responsible for raising the yearly ambient PM2.5 averages would be vehicular emissions, with numerous personal vehicles such as cars and motorbikes traversing the roads on a daily basis, causing large buildups of both chemical pollutants as well as dangerous fine particulate matter. Many of these cars and bikes would run on diesel fuels, which can release a whole host of different pollutants and in greater quantities than a non fossil fuel or cleaner and more sustainable counterpart would.
Other sources of pollution include the somewhat contentious issue of clouds of finely ground dust and sand, coupled with haze and smoke, being blown over from both China and Mongolia. China has a plethora of coal fired plants and factories that besides relying on fossil fuels for their energy, also release large amounts of chemical effluence depending on what product or item is being manufactured. So, whilst it has been speculated that the strong winds coming from the west are responsible for blowing pollution over from China and Mongolia over to Gyeonggi, and indeed the rest of South Korea, some experts weigh in that much of the pollution in the state and country are from homegrown sources.
So, in closing, cars and other vehicles would be large contributors to pollution (including heavy duty ones such as trucks and lorries, which would see prolific use particularly for the mass transporting of products for international export), there would be other pertinent factors playing their part. Local power plants and industrial zones would emit their own fumes, particularly during the colder months when the demand for heating in both homes and businesses would go up considerably due to the large drops in temperature (even more prominent in the northern regions such as Gyeonggi). Others would be sources such as construction sites and the heavy machinery used in them, also running on diesel alongside the numerous different types of fine particulate matter released from construction sites.
Observing the data taken over the course of 2019 as an indicator of which to go by, there emerges a very distinct pattern regarding the peaks in PM2.5 levels and their corresponding months. To once again use the city of Anseong as an example, a distinct rise in pollution levels was seen between the months of September through to November. To demonstrate, September came in with a PM2.5 reading of 12.7 μg/m³, followed by a rise up to 18.4 μg/m³ in October and then an even more significant rise to 27.3 μg/m³ in November. This then increased further to 29.4 μg/m³ in December, before hitting the highest measures of pollution, as were seen throughout the entire state, in the early months of the following year.
Whilst Anseong’s readings are being quoted, it is important to note that all 31 cities in Gyeonggi saw equally bad elevations in their PM2.5 levels during the first three months, with a majority of the cities going up from the moderate pollution bracket into the ‘unhealthy for sensitive groups bracket’, one that requires a PM2.5 reading of anywhere between 35.5 to 55.4 μg/m³ to be classified as such. As the name indicates, this level of air pollution presents a hazard to vulnerable demographics, with the young, elderly, immunocompromised or those with preexisting illnesses and conditions being the most at risk, alongside pregnant mothers.
Anseong presented with readings of 51.4 μg/m³, 47.6 μg/m³ and 50.5 μg/m³ for the months of January through to March, making January the most polluted month of the year for Anseong. To quote some other cities readings, Dangjin also came in with readings of 42.4 μg/m³, 42.4 μg/m³ and 53.1 μg/m³ in the first three months of the year, readings that were well over double of the year’s cleanest readings for that city. In closing, 21 cities in Gyeonggi came in with all three of their first months hitting the ‘unhealthy for sensitive groups’ bracket, eight came in with two months of the year hitting that bracket whilst only two cities came in with a singular reading of the heightened bracket being reached.
This shows that every single city was subject to a jump from moderate pollution levels up to the next most polluted group rating in January to March, and to finish, the period of November through to May of the following year was the time in which pollution levels were at their highest, with January, February and March taking the top spots within this time frame for worst readings of PM2.5.
As touched on briefly in the closing sections of the previous question, it was around the month of May when the polluted levels started to recede somewhat, although of note is that they still remained high for some cities, and whilst they were not as bad as the first three months of the year, they could certainly go a long way to induce improvements in their air quality. Looking at both Anseong and Yeoju for reference, both cities came in with PM2.5 readings of 27.7 μg/m³ and 31.3 μg/m³ in May, which were both followed by 18.3 μg/m³ and 22.2 μg/m³ in June, showing a considerable drop.
This continued for them, and many cities, until the months of August through to October, which had the cleanest air out of the entire year. Anseong had a reading of 12.7 μg/m³ in September, and Yeoju had a reading of 13.7 μg/m³ in the same month. Gwangju saw a reading of 11.5 μg/m³ in September, putting it down a notch into the ‘good’ ratings category, something that was also seen in 12 cities across the state, with their September months falling into both the good target rating as well as the coveted WHO's target goal rating of 10 μg/m³ or less, for the most optimal quality of air.
Some of the main types of pollution found in the air across the state would be ones such as nitrogen dioxide (NO2) and sulfur dioxide (SO2), finding their emission mainly from vehicles. Others would include black carbon and volatile organic compounds (VOC's), both of which find their release from the incomplete combustion of organic material as well as fossil fuels, and as such see their release from factories, engines, construction sites and anywhere that sees some form of combustion taking place. Some examples of VOC's would include ones such as benzene, toluene, xylene and formaldehyde.