Possibility of influx of yellow dust in Korea on the morning of the 16th
Yellow sand observation in spring: 5.5 days in a normal year → Decreased to 2.8 days in the last 5 years
On the morning of the 14th, the whole area of downtown Seoul as viewed from Mt. Inwang, Jongno-gu, Seoul was hazy. On the 16th, yellow dust from China is expected to strike again. yunhap news
As the atmosphere spreads, the concentration of fine dust, which had temporarily faded on the night of the 15th, is expected to rise again on the 16th due to yellow dust originating in China. The Meteorological Administration said on the day that “yellow dust has been extensively originated from the 14th in the vicinity of China’s Inner Mongolia and the Gobi Desert, and very strong in some areas, so it is highly likely to flow into Korea from the early morning or morning of the 16th. The Meteorological Administration explained that a strong wind of 15 to 20 m per second is blowing between the high pressure developed near Lake Baikal in the southern part of Siberia, Russia and the low pressure developed in the northeast of China, causing a wide range of sand breezes. The Meteorological Administration added that if the cyclone in northeastern China advances to the east, there is a high possibility that additional yellow dust will emanate from the back of the cyclone. The Meteorological Administration predicts that there is a high possibility that yellow dust will flow into Korea from the early morning or morning of the 16th when Korea is free from the effects of pressure valleys.
Material photo” alt=”Yellow sand that flows into Korea is mainly originated from the Gobi Desert and Manchuria. A yellow sand breeze (yellow sand breeze) is taking place in the spring in Bayangnor, north of Ulaanbaatar, Mongolia. <한겨레> Material photo” />
Yellow sand that flows into Korea mainly originates from the Gobi Desert and Manchuria. A yellow sand breeze (yellow sand breeze) is taking place in the spring in Bayangnor, north of Ulaanbaatar, Mongolia. Material photo
Yellow dust is dirt dust caused by strong winds in dry areas in East Asia. The Meteorological Administration issues an alert when the average concentration of fine dust (PM10) per hour is expected to last more than 2 hours for more than 2 hours. Yellow sand is a meteorological phenomenon that has been observed since ancient times, and in ancient documents, not only yellow sand, but also Uto, Tou, Hajin, and Honmong appear under 12 different names.
By comparison, fine dust refers to dust with a diameter of 10 μm or less (PM10) among particulate matter floating or scattered in the air, and includes yellow dust, but mainly composed of sulfates and nitrates generated in the process of burning fossil fuels. From 2017, the yellow dust advisory was included in the fine dust advisory and replaced with the fine dust advisory. Fine dust advisory (alarm) is when the average fine dust concentration of 1 hour is expected to last more than 150(300)㎍/㎥ or 75(150)㎍/㎥ or more of ultrafine dust (PM2.5) for more than 2 hours. Is issued. The fine dust forecast has four levels: good, normal, bad, and very bad. The National Institute of Environmental Sciences Air Quality Integrated Forecast Center said on this day, “The concentration of fine dust on the 16th was’very bad’ in the metropolitan area, Gangwon Yeongseo, Chungcheong area, and Honam area due to the influx of yellow sand, and Yeongdong, Gangwon, and Yeongnam area. Jeju area is expected to be’bad’.” In addition, Gangwon Young-dong, Busan, Daegu, Ulsan, Gyeongbuk, Gyeongnam, and Jeju may temporarily become’very bad’ on the afternoon of the 16th, the Institute of Environmental Sciences added.
The source and route of yellow sand that affected Korea from 2002 to 2020. Provided by the National Institute of Meteorology
The number of days of yellow dust observation has decreased in recent years.
Yellow sand occurs in the spring for eight out of ten. It does not occur at all in summer, but is often observed from late autumn to winter.
In particular, the number of days of yellow dust observation has been decreasing in recent years. The number of days of yellow dust observation in spring has decreased to 3.5 days in the last 10 years and 2.8 days in the last 5 years, compared to 5.5 days in the normal year (average of 30 years from 1981 to 2010). The annual total average also tends to be 7 days, 5.1 days, and 4.4 days, respectively. The Meteorological Administration said, “It is estimated that one of the causes is the decrease in the source of yellow dust in the Gobi Desert, which is the main source of Korea, and in northeastern China (Manchuria).” The main sources of yellow dust that affect Korea are the Gobi Desert, Inner Mongolia Plateau, Hwangto Plateau, and Manchuria. In particular, the yellow dust from the Gobi Desert and Manchuria affects Korea the most.
A schematic diagram of the yellow sand observation mechanism in Korea. Provided by the National Institute of Meteorology
Yellow dust is widely originated from the strong winds behind the cold front, and rises and moves in the air by the rising low pressure air current. The moving altitude is 1.5 to 3 km (850 to 700 hectopascals) above the ground, and most of them approach the northwest wind (settlement current) from the northwest of the Korean Peninsula, and are the first to be observed on Baengnyeongdo Island. The time when yellow dust was observed as dense as a yellow dust warning was issued recently was February 22-24, 2015 and April 22-25, 2016. In 2015, the average concentration of PM10 per hour in Seoul was 1044㎍/㎥, and in 2016, 852㎍/㎥ was observed in Baengnyeongdo Island. By Lee Geun-young, staff reporter