The strongest sandstorm this year is coming, why can't the shelterbelt forest stop it?

When I woke up one night, my glass windows were covered with dust. Because the windows were not closed tightly, I spent the whole morning cleaning the dust on the floor, and all the clothes hanging on the balcony needed to be washed again.

Yes, the dust storm is coming again. Why is there so much dust storm this year? From March 10th to now, Beijing has experienced three rounds of dust storms. Not only that, Inner Mongolia, Ningxia, Shanxi, Shaanxi and other regions have seen more dusty weather, and some areas have also seen more serious sandstorms. After the 1990s, the term sandstorm gradually faded from our sight. Why is it so obvious this year?

How do sandstorms come about?

Dust, of course, does not appear out of thin air. It comes from arid and semi-arid land. Due to the strong wind, the dust on the surface is carried along, affecting northern China and even other countries in East Asia.

The sources of sand and dust that affect my country are mainly Xinjiang, Gansu, Inner Mongolia and other places within China, and mainly Mongolia outside China. They are all deserts, wastelands and Gobi areas deep inland, far from the ocean, with arid climate and poor vegetation. Because the above-mentioned areas do not have much precipitation in winter and spring, the surface, which is already weak in wind erosion, lacks moisture and vegetation coverage, and its ability to resist strong winds is further reduced. Therefore, when the sand comes from the source area, it is a strong wind, and when it leaves, it becomes wind and sand.

The dust source area has existed for a long time, but the dust weather was so obvious in March this year, which is closely related to the weather and climate. Since late February this year, the temperature in the dust source area has continued to rise, the soil thawed quickly, and the precipitation was relatively low, so the surface was very dry and loose. When the Mongolian cyclone triggered by the cold wave came, the unstable atmospheric conditions swept the surface dust into the air, and the dust took a ride with the eastward movement of the weather system.

The dust is ready to go, and the air is ready to go. The combination of the two has caused sandstorms that fill our eyes with yellow sand. The area affected by this sandstorm is the largest so far this year, and it can be said to be very extensive. Most areas in the north have been affected, and the northwest, north China, northeast China, and northeast China are all affected. However, the southern region is still spared this time, because the seasonal precipitation weather process blocks the dust from reaching the south of the Huaihe River, and friends in the southern region still have no chance to experience the feeling of being harassed by yellow sand.

How to protect yourself during sandstorms?

In any case, March this year can be regarded as a sandstorm month for our friends in the north. So how should we protect ourselves during sandstorms?

1. Go out less

To be honest, it is not realistic for most people to stay at home, but when sandstorms occur, it is best not to go out. Because the air at this time contains a large amount of PM2.5 and ultrafine particles, basically every breath you take is a strong irritation to the respiratory tract. If you really have to go out, be sure to wear a mask and try to shorten the time outdoors.

If you have cardiovascular or respiratory diseases, try not to go out. High concentrations of ultrafine particles can induce some acute respiratory problems, such as acute cardiovascular problems and asthma, etc. The consequences are serious, so try not to take risks.

2. Wear the right mask

Choose the right mask. Medical masks or ordinary masks are not recommended. Although they are comfortable to wear, they are not very effective in protecting against ultrafine particles. It is best to use KN95 or N95. If you really don't have them, you can use KN90 or N90. By the way, if you don't care about the air you exhale containing germs, you can also wear models with breathing valves.

3. Wash your hands, face, hair and take a bath after returning home

Strong winds not only blow up dust, but also various pollutants, such as pathogens from trash cans and pollens from flowers that can cause allergies. When you pass through the dust, these pollutants will remain on your face, hair, and even clothes. If you don't deal with them in time, these pathogens and allergens may slip into your body through your mouth and nose. You don't need special detergents to clean these dirt, just use your daily facial cleanser and shampoo.

4. Rinse your nose

If you have an allergic constitution, it is recommended to wash your nasal cavity after taking a shower. Although you wear a mask, there may still be some bacteria living in your nasal cavity, so it is also a good choice to rinse your nasal cavity with saline (or water if you don't have it) after returning home. In addition, when pollen is rampant in spring, "nasal washing" can also solve big problems.

5. Turn on fresh air and air purifier

That's right, even if you have closed the doors and windows long before the sandstorm hits, it is still recommended that you turn on the air purifier and operate it manually. If your air purifier is automatically detected, they can often only monitor PM2.5, but seem to be somewhat blind to PM10. Therefore, it is best to manually turn on the high wind gear to ensure that they work strongly during sandstorms and filter out the dust that penetrates through the door and window gaps. Remember to manually clean or replace the filter and filter element after the sandstorm. After all, the air purifier is also full of pressure after this kind of weather.

By the way, during the sandstorm, the sky sometimes looks a little red, which makes people wonder if the world is about to end. Don't worry about this, it's just the dust floating in the air that scatters the sunlight, and no monsters will emerge from it.

The article is produced by Science Popularization China-Starry Sky Project (Creation and Cultivation). Please indicate the source when reprinting.

Author: Hydra Science Author

Reviewer: Ai Wanxiu, Chief Senior Engineer, Climate Service Office, National Climate Center