Unwelcome Guest: Fine Dust from China Covers Seoul After 110 Days

Seoul Metropolitan and Chungcheong Regions at 'Bad' Level
Air Stagnation Due to Large Temperature Differences in Transitional Season

On the 20th, the city center viewed from Sinmunno, Jongno-gu, Seoul, where the fine dust concentration in the metropolitan area is recorded as 'Bad,' is shrouded in fine dust. Photo by Jinhyung Kang aymsdream@

[Asia Economy Reporter Lee Hyun-joo] Fine dust has returned to Seoul after 110 days. The stagnant atmosphere and inflow from China are cited as causes.

Since the morning of the 20th, fine dust levels have reached 'bad' mainly in the metropolitan area and Chungcheong region. It is the first time in 110 days since July 2 that the daily average concentration of ultrafine dust in Seoul has risen to a bad level. As of 9 a.m., some areas such as Siheung in Gyeonggi Province recorded ultrafine dust (PM2.5) at 94㎍/㎥ and Gwangmyeong at 81㎍/㎥, showing a 'very bad' condition.

The Korea Environment Corporation stated, "In the central-western region and parts of Honam, the concentration is expected to remain high due to residual fine dust from the previous day, domestic fine dust emissions, and additional inflow of foreign fine dust."

Autumn fine dust is related to cold weather. Around late October, cold winds blow from China to Korea along the northwesterly airflow, carrying fine dust into the Korean Peninsula. The corporation explained, "This fine dust also came from dust near Shandong and the Bohai Bay in China, carried by westerly winds."

Fine Dust (PM-2.5) Air Quality Concentration Forecast (Provided by Air Korea Website)

The large temperature difference during the transitional season also increases fine dust concentration. On days with a large temperature difference, the temperature at higher altitudes does not drop, but the temperature near the ground falls sharply, making atmospheric circulation difficult. This is also why fog frequently forms on days with large temperature differences. Generally, fine dust concentrations tend to be 'bad' during winter and continue into the following spring. However, this winter presents variables unlike previous years, such as reduced economic activity due to the COVID-19 pandemic, policy effects, and an unusually long rainy season. These factors also led to fewer days with bad fine dust levels last spring compared to usual years. Lee Dae-gyun, head of the Air Quality Integrated Forecast Center at the National Institute of Environmental Research, said, "Considering various situations, it is still difficult to predict fine dust concentrations for this winter."

This content was produced with the assistance of AI translation services.