How is the fog formed?

Fog refers to water vapor condensate composed of water droplets or ice crystals suspended in the near-surface atmosphere, which is a common weather phenomenon.

If the air contains more water vapor than saturated water vapor at a certain temperature, the excess water vapor will condense out. When enough water molecules combine with tiny dust particles in the air, the water molecules themselves will combine with each other and become small water droplets or ice crystals. When the water vapor contained in the air reaches the maximum, it reaches saturation.

The higher the air temperature, the more water vapor it contains. The water vapor in the air exceeds saturation and condenses into water droplets, which is mainly caused by the temperature drop. This is why it is foggy in autumn and winter morning. In autumn, winter and spring, when the temperature is lowest in the morning, the fog is thickest. Fog can actually be said to be clouds near the ground.

Effects of fog:

1. Air transport: Due to extremely low visibility, the aircraft can't take off and land normally, which may lead to large-scale flight delays and cancellations, and affect passenger travel plans.

2. Land transportation: the visibility of highways, national highways and other roads is reduced, which increases the risk of automobile driving and may lead to frequent traffic accidents. In severe cases, temporary road closure measures will be taken to ensure traffic safety.

3. Urban public transportation: Public transportation such as buses and subways may be delayed or adjusted due to road conditions. At the same time, foggy weather will also encourage more citizens to choose public transportation instead of cycling or walking.

4. Economic operation: the logistics industry is blocked, the efficiency of cargo transportation is reduced, and commercial activities are affected, especially those industries that rely on timeliness, such as express mail and fresh products. The operation safety of industrial and mining enterprises is challenged, and some open-air operations and aerial operations may be forced to suspend.

5. Energy supply and facility safety: Fog may bring certain security risks to power lines, communication facilities and other infrastructure, so it is necessary to strengthen monitoring and maintenance.