Yellow dust remains a chronic headache for peninsula, adding to spring air quality problems
On the coattails of Korea's first emergency emission reduction measure of the year on Tuesday forced by heavy concentrations of ultrafine dust, the weather authorities on Wednesday issued a warning against an influx of yellow dust that afternoon.
The Korea Meteorological Administration forecast that dust originating from deserts in China and Mongolia will be brought in on a northwestern wind and cover the peninsula until Friday. It will start affecting the five islands of the West Sea and central coastal regions in Gyeonggi Province this afternoon, eventually expanding throughout the country late at night.
Much of East Asia experiences high levels of ultrafine dust year-round but in Korea, these levels are more severe in spring. This makes the season a particularly trying time for Koreans, especially in March, which has infamously-high levels of ultrafine dust.
Yellow dust a chronic issue in spring
Seoul on average had 8.9 days of yellow dust a year between 1991 and 2020, with 2.2 in March and 3.1 in April, according to the KMA. But the number of days with high dust levels have increased in recent years, recording an average of 9.3 in the past 10 years and 10.6 in the past five years — from 2020 to 2024 to be exact.
There were 19 days in 2023 when the city had yellow dust, and 14 days in 2021. Since 2000, the worst year in terms of yellow dust came in 2001, when the city was covered with yellow dust for 27 days.
That year was also the worst-ever for all observed regions in the country, with an average of 23.1 days of yellow dust recorded nationwide.
Ultrafine dust levels in Seoul were even higher than in Incheon, the nation's westernmost metropolis. Incheon recorded an average of 8.6 days of yellow dust between 1991 and 2020, with the recent 10-year and five-year averages both being at 8.2.
The oldest records of yellow dust problems on the peninsula can be dated back to 2nd century mentions of "dirt rain" during the Silla Kingdom, but the meteorological phenomenon is believed to have escalated in modern times with rapid industrialization and ongoing desertification in East Asia.
Springtime air pollution presents more than mere nuisance for Koreans, as high levels of ultrafine dust can trigger pulmonary conditions and even lead to skin, blood and heart issues.
A study published earlier this month indicated that ultrafine dust particles can also lead to depression. Researchers at Wonju Severance Christian Hospital found that exposure to ultrafine dust could trigger certain responses in the brain, such as inducing the stress reaction on the hypothalamus.
This can lead to behavioral changes that are similar to depression, according to the study.
Ultrafine dust problems persist
According to the KMA, the ultrafine dust concentration levels, which had already reached "bad" in Greater Seoul (Seoul, Incheon and Gyeonggi Province) and South Chungcheong Province on Tuesday, are expected to remain "bad" in the same regions as well as the Jeolla Provinces on Thursday. Levels are expected to temporarily reach "very bad" in the Gyeongsang Provinces.
Light rain forecast for the capital region on Wednesday afternoon will not be sufficient to lower the dust concentration levels, the KMA said.
The weather authorities release warnings based on the concentration of dust particles smaller than 2.5 micrometers in diameter, known as PM 2.5. Concentrations of ultrafine dust between 0 and 15 micrograms per cubic meter are classified as "good," while 16 to 35 is considered "normal," 36 to 75 is "bad," and 76 and above is "very bad."
minsikyoon@heraldcorp.com
