Why is there so much smog in Beijing in winter?

The reasons for winter smog in Beijing are as follows:

1, Beijing has a developed economy and a high penetration rate of private cars. Vehicle exhaust is the main component of smog particles. The latest data shows that motor vehicle exhaust accounts for 22.2% of smog particles in Beijing.

2. In winter in Beijing, the exhaust gas produced by burning coal for heating is also an important part of smog.

3. In the process of urbanization since the reform and opening up, Beijing's industrial production has emitted a lot of waste gas. For example, metallurgy, kilns and boilers, electromechanical manufacturing, automobile repair and paint and building materials production produce a lot of waste gas from kiln combustion.

4. The higher the buildings in Beijing urban area are built, the obstruction and friction of airflow passing through the urban area will be obviously weakened. The increase of static wind phenomenon is not conducive to the diffusion and dilution of suspended particles in the atmosphere, and it is easy to accumulate around urban areas and suburbs.

5. Dust "smog" will also appear 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.

Extended data:

Hazards of smoke:

1, lung injury: smog weather weakens the surface ultraviolet rays and easily increases the activity of bacteria in the air. Fine particles can "carry" viruses and bacteria deep into the respiratory system, causing infection.

2. Injury to the heart: Particulate pollutants on cloudy days will not only cause myocardial infarction, but also cause myocardial ischemia or injury.

3, injured blood vessels: dense fog weather pressure is relatively low, people will feel irritable, blood pressure will naturally rise. Some patients with hypertension and coronary heart disease suddenly go from warm indoor to cold outdoor, and blood vessels expand with heat and contract with cold, which will also increase blood pressure, leading to stroke and myocardial infarction.

4, damage to the skin: the skin also has a respiratory function. In clean air, the skin will be very comfortable and moist, but in very dirty environment, the skin will be very uncomfortable.

5, brain damage: smog not only harms organs, but also affects this nervous system invisibly.

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