Dust storms from Mongolia are back, here are some precautions you need to know

Affected by the Mongolian cyclone, sandstorms will return this weekend! The farthest impact will be in Hubei, Henan, and Anhui. What are the health hazards of sandstorms? How to prevent them? You need to know these>>>

Written by reporter Han Jibo and Chen Xuanzhi; New media editor: Chen Xuanzhi

Starting from the afternoon of March 27, the main body of sand and dust originating from the central region of Mongolia began to enter my country. Most of Inner Mongolia, northern Shanxi and northern Hebei will be affected first, and the air quality will be mainly heavy to severe pollution.

▎Affected by the Mongolian cyclone, sandstorms are back

Affected by the Mongolian cyclone, the sandstorm will return this time. There will be blowing sand or dust weather in the eastern Xinjiang and southern Xinjiang Basin, northwestern Qinghai, Inner Mongolia, Ningxia, central and eastern Gansu, central and northern Shaanxi, Shanxi, Hebei, Beijing, Tianjin, Shandong, Henan, northern Anhui, northern Jiangsu, western Liaoning, western Jilin, southwestern Heilongjiang and other places.

Among them, there will be sandstorms in parts of central, western and southeastern Inner Mongolia, northern Hebei, northern Beijing, western Liaoning and other places, and strong sandstorms in the northern part of central Inner Mongolia.

During this period, Inner Mongolia, northern North China, Shandong Peninsula, western Liaoning Peninsula and other places will have winds of 4 to 6, and gusts may reach 7 to 9.

▲National sandstorm weather forecast map (Source: Central Meteorological Observatory)

▎Dust pollution moves slowly, and the value needs to be determined based on nearby satellite remote sensing results

According to the latest forecast from the Central Meteorological Observatory, from 8:00 on the 26th to 8:00 on the 27th, there will be blowing sand or dust weather in eastern Xinjiang and the southern Xinjiang Basin, central and western Inner Mongolia, central and western Gansu, northern and eastern Qinghai, Ningxia, and northwestern Shaanxi. Among them, there will be local sandstorms in western Inner Mongolia and western Gansu.

▲National sandstorm weather forecast map (Source: Central Meteorological Observatory)

According to the forecast of the China National Environmental Monitoring Center, starting from the daytime of the 27th, the central and eastern Inner Mongolia, Ningxia, Shaanxi, Shanxi, Beijing-Tianjin-Hebei, Liaoning and some areas of my country are expected to be affected by the transmission of sandstorms from northwest to southeast. Cities through which sandstorms pass may experience severe or above pollution.

On the 28th, with the continued support of the weak high-pressure system in the northwest, the sandstorm pollution group will continue to move eastward and southward, affecting the Fenwei Plain, central and southern North China, and parts of Northeast my country.

From the 29th to the 30th, under the combined influence of continued weak northerly winds and precipitation in central China, the impact of this sandstorm pollution process on air quality gradually came to an end.

Compared with the recent strong sandstorm weather this month, the movement speed of this sandstorm pollution process may be slow due to the weak high-pressure system behind it. The amount of sand raised and the concentration of transit pollutants still need to be judged based on the remote sensing results of nearby satellites.

The monitoring results of the China National Environmental Monitoring Center confirmed that the impact of sandstorms can be judged by the concentration of calcium ions in particulate matter. Taking Beijing as an example, during the high-intensity sandstorm weather in the middle of this month, the concentration of particulate matter increased by more than 30 times; during the same period, the concentration of calcium ions (Ca2+) in particulate matter was about 30 times that of the non-sandstorm period, which was consistent with the trend of particulate matter concentration changes.

▎The farthest stop was in Hubei, Henan and Anhui, and its intensity was slightly weaker than that of the dust storm on March 18

It is expected that the main part of this dust storm will leave China through Northeast my country, and the dust stranded in North China will continue to move southward to affect Shandong and most of Henan due to the continuous weak northerly wind. Due to the large-scale precipitation in the middle and lower reaches of the Yangtze River on the 29th, the dust storm is expected to stop at the northern part of Hubei, Anhui and central Jiangsu.

Compared with the strong sandstorm weather process that ended on March 18, the intensity of this sandstorm weather process is slightly weaker, the sandstorm affected the east, the range of the strong sandstorm was smaller, and the range of sand or dust transmission to the south was slightly smaller.

Beijing began to be affected by the passage of sandstorms from the night of the 27th to the early morning of the 28th, and the air quality was mainly severely polluted; after the main body of the sandstorm passed on the 29th, the air quality gradually improved.

However, within the affected area of ​​this process, there will be visible yellow sand weather. The public still needs to take measures to prevent wind and dust, and it is best to stay at home and spend the weekend in peace.

▎Sandstorms not only irritate the upper respiratory tract, but also spread certain diseases

In such weather, if you do not take protective measures and inhale a lot of sand and dust, it will cause harm to your health. So what are the specific hazards of sandstorms?

Cheng Yang, deputy chief physician of the respiratory and critical care department of Beijing Jishuitan Hospital, pointed out that sandstorms have the following seven major hazards:

Hazard 1

In addition to strong winds, sandstorms are mixed with a large number of particulate matter, which can be deposited in various organs of the human body. The harm of particulate matter to the human body is related to its particle size and shape: the particles that make up haze are mainly PM2.5 (particles with a diameter less than or equal to 2.5μm). PM2.5 can directly enter and attach to the trachea, bronchi, and even reach the alveoli, inducing infection, inflammation or immune response, and even causing chronic bronchitis, emphysema, pneumoconiosis and other diseases. The particles in sandstorms are larger, generally with a diameter of more than PM10. After PM10 is inhaled, it is deposited in the upper respiratory tract, and at the same time, through the movement of cilia, it is expelled from the body with coughing and sneezing. These particles will irritate the upper respiratory tract, destroy the defense function of the respiratory system, and cause upper respiratory symptoms such as nasal congestion, runny nose, sore throat, and coughing. In fact, sandstorms also have PM2.5, so they will have a double blow to the upper and lower respiratory tracts. In addition, dust particles deposit on the skin, blocking skin glands and sweat glands, causing itching, redness, swelling, and rashes; particles enter the eyes, causing a foreign body sensation in the eyes, tearing, and even developing into eye diseases such as conjunctivitis.

Hazard 2

Dust storms are mixed with a large amount of allergens such as pollen, which are transmitted from far away to the local area. Some people who have no history of allergies in the local area may experience many allergic symptoms during sandstorm weather, such as allergic rhinitis, allergic dermatitis, etc.

Hazard Three

Dust storms are also mixed with a large number of bacteria, viruses and other substances that are harmful to the human body. When they enter the body with the sand and dust, they can cause infection in the corresponding parts of the body. For example, if they enter the upper respiratory tract, they can cause bacterial or viral rhinitis and pharyngitis; if they enter the lower respiratory tract, they can cause bronchitis and pneumonia; if they enter the gastrointestinal tract and eyes, they can cause gastroenteritis and conjunctivitis, respectively. At the same time, infection can cause the aggravation of existing chronic diseases. Therefore, sandstorms are considered to be the medium for spreading certain diseases. It was once reported that due to the influence of sandstorms, the number of citizens infected with "streptococci" in a place increased sharply.

Hazard 4

Ultraviolet rays have a bactericidal and sterilizing effect. Sandstorms can affect the radiation intensity of ultraviolet rays, causing pathogens to spread through the air. At the same time, ultraviolet rays with a wavelength of 290 to 315 nm can promote the conversion of 7-dehydrocholesterol into vitamin D, which can prevent the occurrence of rickets in children. Therefore, areas where sandstorms often occur will lead to an increase in the incidence of rickets in children.

Hazard 5

Polycyclic aromatic hydrocarbons, heavy metals and other organic substances adsorbed on particulate matter are highly mutagenic and carcinogenic.

Hazard 6

Some research reports also suggest that sandstorm weather can lead to frequent cardiovascular and cerebrovascular events, such as coronary heart disease, myocardial infarction, and stroke.

Hazard 7

Sandstorms also have a great negative impact on people's mental health. First, when a sandstorm occurs, the collision and friction noise of air and sand will make people feel uncomfortable; especially the low sound of strong winds can directly affect the human nervous system, causing headaches, nausea, and irritability. Secondly, when a sandstorm strikes, visibility is low and the light is dim, which makes people feel depressed and fearful.

▎To protect against sandstorms, close doors and windows at home and wear protective masks when going out

1. When sandstorms occur, residents should stay indoors as much as possible and take appropriate measures

① Close doors and windows in time. If necessary, seal them with tape to prevent sand and dust from entering the room.

② Use wet dust removal methods such as mopping the floor with a wet mop and wiping with a wet rag to keep the room clean and avoid re-suspension of indoor dust.

③You can use humidifiers, sprinklers and other methods to maintain appropriate air humidity.

④If conditions permit, turn on the air purifier indoors.

2. If you need to go out, you should pay attention to personal protection

① Wear a mask to reduce the damage of wind and sand to the respiratory tract. In sandstorm weather, there will be floating dust, inhalable particles and fine particles at the same time, so it is advisable to wear N95 or above protective masks.

② Wear windproof glasses to prevent wind and sand from damaging your eyes. If wind and sand enter your eyes, do not rub them with your hands. Rinse with running water or use eye drops as soon as possible. If you still feel uncomfortable, seek medical attention immediately.

③ Wear hats, scarves and other dust-proof equipment, and wrap your head with the scarf to prevent wind and sand from damaging your skin, hair, ears, etc.

④ After returning from outside, you should wash your hands and face immediately, rinse your mouth with clean water, clean your nasal cavity, take a bath if conditions permit, and change clothes in time to keep your body clean and comfortable. In addition, during sandstorm weather, the air is dry, which can easily cause chapped lips, dry and itchy nose and throat. You should drink more water and eat more fruits and vegetables rich in vitamins to keep your respiratory tract unobstructed and moist, and relieve the discomfort of the throat.

▎Sandstorms can only be prevented, they cannot be eliminated

So, is it possible for sandstorms to disappear completely through human control in the future? The answer is no. Because as long as the three basic conditions of sand source, strong wind and unstable atmospheric stratification are met, sandstorm weather will occur. In northern my country, spring is often dry and rainy, and these three conditions are easier to meet than in other seasons, and therefore sandstorm weather is most common.

The reasons why sandstorms are unlikely to disappear are:

Firstly, strong winds and unstable atmospheric stratification are normal phenomena of atmospheric movement and cannot be eliminated by human power.

Secondly, as the source of sand, the desert is also an important part of the earth's natural environment. my country's sand prevention and control work is based on respecting nature, adapting to local conditions, and scientifically controlling sand. Controlling sand is not about "eliminating" the desert, but about controlling the desertified land caused by humans. If the three conditions cannot be eliminated, there is no way to eradicate sandstorms.

In addition, sandstorms are a natural phenomenon that has both advantages and disadvantages for the environment and people. Based on current scientific knowledge, the disadvantages outweigh the advantages. The disadvantages are mainly that sandstorms pollute the air and harm the health of people and animals; the strong winds and low visibility of sandstorms can easily cause meteorological disasters and secondary disasters such as casualties and damage to infrastructure. Some researchers believe that sandstorms also have benefits such as alleviating acid rain and promoting the growth of marine life. These views are reasonable, but the magnitude of the advantages is far lower than the disadvantages, or they are not on the same time scale.

We should also realize that sand prevention and control and afforestation can indeed reduce and alleviate sandstorm weather, but it is neither necessary nor possible to fantasize about eliminating sandstorms as a natural phenomenon. On the contrary, the correct attitude we should take in the face of sandstorms is to correctly understand the laws of sandstorm weather, do preventive work in advance, minimize losses as much as possible, and fight a "prepared battle."

(Part of the content is compiled from Guangming Daily, Xinhua News Agency, Guangming.com, China News Network, Xinhuanet Science, China Weather Network, Tianjin Science, etc.)

Produced by: Science Central Kitchen

Produced by: Beijing Science and Technology News | Science Plus Client