[Writer’s Choice] Yellow Dust
BanSeok Shin, Feb. 28, 2019, 3:22 p.m.
If you are planning to travel to South Korea, especially during the first half of the year, then you need to be aware of Yellow Dust which can negatively affect your health while you are there. Hwang-sa is the Korean word for this both natural and unnatural phenomenon which impacts the Korean Peninsula as well as a large part of East Asia each year. Also known as Asian Dust, or more popularly - fine dust, this phenomenon, which has been experienced for thousands of years, can occur during anytime of the year but is especially prominent during the spring time.
Yellow dust isn’t to be confused with the haze that frequently covers areas like Seoul and which also can be both natural and unnaturally occuring. However, the haze can and often does mix with yellow dust making it worse if the haze is primary caused by air pollution. Yellow Dust refers to large amounts of dust that are thrown into the air and are carried over long distances. This dust typically originates from deserts and other arid or dry regions like the deserts in China and Mongolia, and even as far as Kazakhstan and other parts of Central Asia. In addition to naturally existing areas such as the Gobi Desert (Northern China & Southern Mongolia) there are many places in the previously mentioned areas where land has become arid (or more arid) due to various natural and unnatural factors such as erosion, deforestation, climate change, and others. As a result of this, the potential for more frequent and severe Yellow Dust occurrences has increased over the years and continues to do so as time goes on. This potential is realized when high speed winds create large dust storms by sweeping up not only the dirt and sand in these regions, but also the heavy metals located in them, pesticides and other contaminants (found in both the ground and in the air), as well as bio-agents like fungi, viruses, and bacteria.
Yellow Dust in Seoul
Haze Covering Seoul
Sand Being Carried of the Ground by Strong Winds
All of these pollutants - as you can imagine - can negatively affect a person’s health. But it is not only people who are directly affected, but crops, wildlife, and even open sources of water are too. Furthermore, as dust is carried along by wind currents it can fall at any and all points along the way with regions closer to the source usually receiving more dust fall. Dust can travel all the way to South Korea, Japan, and has been known to even cross the Pacific Ocean to the United States. Fortunately, for those who are located further away the severity of dust they experience is usually much less. Despite this East Asia still experiences periods where the dust levels are high enough to be considered by many as a public health hazard.
Polution from a Chinese Factory
South Korea uses a three-level system, provided by the Korean Meteorological Administration (KMA), to advise the public about the presence of yellow dust and take precautions for at-risk groups. The system is based on the density – or the concentration of dust particles in the air. The first and lowest level encourages the elderly, young children, and those with respiratory problems, to stay inside and it’s recommended that for everyone to limit the amount of outdoor activity they do. The second level takes level one a step further by advising that the three previously mentioned groups stay inside and all others to further limit outdoor activities. The highest level strongly advises everyone to stay indoors and even for outdoor events to be moved to another time or date.
In all cases of there being a yellow dust warning in affect people should take precautions to protect themselves and others from the dust. On days with higher levels of dust in the air people should wear protective eyewear, masks, long-sleeve clothing, and even a hat. Dust and sand can also get in the eyes and can accumulate on your skin and clothes. Some yellow dust is very difficult to block as it occurs in the form of fine and ultra-fine dust which can go through masks. This is because the particles are so small that they easily pass through the small, sometimes microscopic holes of commonly used masks. That is why the best way to avoid yellow dust exposure is simply to remain indoors with windows and doors kept closed. Additionally, air filters can help in keeping an indoor area free of yellow dust.
Yellow Dust can cause irritation in the eyes and airways as well as weaken the immune system.
If, for whatever reason, you find yourself outside during elevated levels of yellow dust here are some additional safety tips: wash anything you go outside with as soon as you can, wash any exposed body parts - especially your face and hands, make sure to wash any food that has been exposed to the dust, take care of your immune system, stay hydrated, and be weary of stirring up dust that has fallen – even after the storm has ended. Even when it is raining yellow dust can still be a problem – not only in the air, but also in the water (like acid rain) and can even stain clothing. If you don't have a mask there's a good chance you might be able t buy one at a convience store.
It is wise to keep yourself aware of the current conditions or future forecasts of yellow dust as storms can occur any time of the year and sometimes forecasts can change with short notice. Various websites, news stations, and mobile weather applications provide forecasts (the KMA does so during yellow dust season) and will issue warnings as well. The city of Seoul sends out text message alerts (in Korean) to people in the Seoul and Greater Seoul area when the air quality becomes a concern. The KMA actually has up-to-date satellite images of East Asia that shows levels of yellow dust. Images are taken in intervals and can be played in short time lapses to see the progression of a storm over time. An analysis chart is also provided as well as a time-series chart that records the highest concentrations of yellow dust each day for different areas around South Korea. The AirKorea website (not to be confused with Korean Air) also provides information about the current air quality and how it has been over the past couple of months.
KMA satellite radar image of fine dust on January 28th, 2019 at 1:45 pm Korean time. The red dots represent monitoring stations.