Causes and hazards of smog formation

The causes and hazards of smog have become more and more serious in recent years, and smog is mainly caused by air pollution. It is light yellow or black fog, which has great influence on health. What are the causes and hazards of smog?

Causes and hazards of haze 1 The main reasons for haze weather are as follows:

First, the discharge of pollutants is large. Coal burning, motor vehicles, industry, dust, these pollution sources emit a lot, which is the root cause of serious pollution. In big cities, various pollutants PM2.5 brought by urban operation are well known. Source monitoring, harm and protection emissions are very large. When the diffusion conditions of pollution are unfavorable, it is difficult for pollutants discharged from pollution sources to diffuse, and air pollution is aggravated.

Second, the diffusion conditions are unfavorable. The recent extremely unfavorable pollution diffusion conditions are the direct cause of this pollution process. Due to the low pressure control of ground closure, the ground wind speed decreased and the humidity increased, which gradually formed the inverse temperature of air intake and the extreme weather diffusion of fog, and the continuous accumulation caused this pollution process.

Third, the contribution of regional pollution and local pollution is superimposed. Due to the regional pollution of PM2.5 and the pollution transmission in related areas, it is also an important factor to form heavy pollution.

In addition, air pollution involves industrial structure, energy structure, urban planning and so on. Take Beijing as an example: first, the vegetation hundreds of kilometers away is destroyed, the exposed topsoil is greatly increased, and the dust is transported to the city for a long distance; Second, the urban-rural fringe has built many buildings behind the central city, and the dust is flying outside the Fifth and Sixth Ring Roads; The third is the pollutant discharge from industrial production and daily life, including coal-fired boilers, motor vehicle exhaust, cooking fumes, volatiles from gas stations and home decoration. Fourth, the pollutant emissions of heavy chemical industries in surrounding cities, such as the contribution of surrounding cities to Beijing PM 2.5 emissions is close to a quarter.

Haze weather hazards:

1, Harm to human body: Due to a large number of toxic and harmful small particles mixed in the smog, people will enter the respiratory tract and lungs with the air when breathing, which may lead to bronchitis, pneumonia and other diseases, and even more serious diseases.

2. Harm to work and life: Haze weather has low visibility, which has an impact on aviation, railways, shipping, highways and other transportation industries, easily leading to traffic accidents and disrupting normal work and life order. At the same time, it is corrosive to buildings, vehicles and other solid objects.

Causes and harm of smog 2 What are the causes of smog weather?

Fog refers to the weather phenomenon that the visibility is lower than 1 km due to the condensation of suspended water vapor in the atmosphere. The formation of smog is mainly the result of a large number of suspended particles in the air and meteorological conditions. There are three reasons for the formation of haze weather:

1, the phenomenon of increasing static wind in horizontal direction.

2. There is an inversion in the vertical direction.

3. The increase of suspended particles in the air.

With the growth of urban population and industrial development, the number of motor vehicles has soared, and the emissions of pollutants and suspended solids have increased greatly, which directly leads to the decline of visibility. In fact, dust "smog" will also occur in home decoration, and indoor dust is pervasive, which is not only harmful to the health of staff and users, but also increases the cleaning burden. When the dust is serious, it will also bring many hidden dangers to the decoration project.

In addition to meteorological conditions, the increase of atmospheric particulate matter (including coarse particulate matter PM 10 and fine particulate matter PM2.5) caused by industrial production, vehicle exhaust emissions and coal burning in winter is an important factor of smog. At present, the level of pollutant discharge in many cities is at a critical point, which is very sensitive to meteorological conditions. When diffusion conditions are good, the air quality can reach the standard, and once adverse weather conditions are encountered, the air quality and visibility will drop rapidly.

Smog weather has an important impact on roads, railways and human health.

Hazards of smog

1, affecting life

Haze weather has an important impact on roads, railways, aviation, shipping, power supply systems and crop growth. Fog and haze will cause air quality decline, affect the ecological environment and bring great harm to human health.

2. Affect traffic

Due to poor air quality and low visibility in foggy days, rear-end collision accidents are prone to occur, which will affect the normal traffic order and have no change in everyone's travel. We should observe the road conditions more during daily driving to avoid danger.

Smoke and smoke prevention

1, reduce going out

The elderly, children and people susceptible to respiratory diseases with weak resistance should try to reduce going out or outdoor activities, and wear masks to protect their bodies when going out to prevent pollutants from invading the lungs through the nose and mouth. After returning from going out, you should immediately wash your face and expose your skin.

Step 2 close the doors and windows

Because the pollutants in the air are difficult to dissipate in foggy days, doors and windows should be closed in foggy days to avoid outdoor fog entering the room to pollute the indoor air and induce acute respiratory and cardiovascular diseases.

Step 3 pay attention to your diet

Patients with chronic respiratory diseases, especially the elderly, should keep scientific life rules, avoid overwork and drink plenty of water. Pay attention to a light diet, eat less irritating food, eat more tofu, milk and other foods, and supplement vitamin D when necessary.

Causes and harm of smog 3 What is smog?

Haze is mainly caused by air pollution. It is a light yellow or black fog, and it is a polluted mixture, which is mainly formed by tiny particles in the atmosphere and ground ozone. Smog causes difficulty in breathing and has a negative impact on human health.

How is the smog formed?

Smoke is formed by pollutants or gases released when fuel is burned. When sunlight and its heat come into contact with these gases and tiny particles, smoke will be formed. It is purely caused by air pollution. The complex photochemical reaction between volatile organic compounds, sulfur dioxide and nitrogen oxides releases the ground ozone layer and tiny particles into the air. These harmful compounds are pollutants released by the combustion of motor vehicle gasoline and diesel oil, which are directly discharged into the air by factories and various human heating activities.

Smog is often caused by traffic congestion, high temperature, sunshine and no wind. These are also several factors that lead to air pollution. In winter, when the wind speed is low, it is easier to form smog, which increases the degree of air pollution that people breathe on the ground. It not only affects vision, but also damages the environment.

The formation of smog is directly related to temperature. Inversion is a phenomenon that warm air stays near the ground instead of rising. If there is no wind during the inversion period, the smog will stay for many days. Of course, smog will be more serious because of pollution release. This is because the smog produced by pollutants released by traffic congestion through photochemical reactions is the mainstream. Smog not only affects big cities, but also appears in suburbs and rural areas.

The influence of smoke

The harm of smog is obvious. It is harmful to humans, animals and plants. Many deaths are related to bronchial diseases. Severe smog will greatly reduce ultraviolet rays and indirectly lead to a decrease in the secretion of vitamin D, thus becoming one of the reasons why some people suffer from rickets.

When a city or town is shrouded in smog, people will feel it immediately. Smog can cause inflammation of eyes, inflammation of lung tissue, chest tightness and pain. In addition, smog can easily induce diseases such as colds and pneumonia. Long-term exposure to smog can also induce lung diseases, even fatal diseases such as lung cancer.

A small amount of exposure to smoke has the risk of inducing asthma attacks. Therefore, asthma patients should avoid contact with smog. Haze can also lead to premature death and gather to dangerous levels in densely populated areas. The people most affected by smog include the elderly, children and patients with heart and respiratory diseases.

Ground ozone in smog can also inhibit plant growth and cause damage to crops. Crops and vegetables such as soybeans, wheat, potatoes, peanuts and cotton have all been affected by smog. Smog threatens the environment, killing many animals and green life, because they need time to get used to breathing and live in a toxic environment.

In short, smog is a devastating problem, especially when harmful chemicals form smog due to rapid modernization or industrialization. This is why governments all over the world are taking measures to reduce pollution emissions.