Weather in Shandong: What are the characteristics of this heavy fog?

Weather in Shandong: Fog is characterized by visibility less than 200 meters.

Fog refers to water vapor condensate composed of small water droplets or ice crystals suspended in the near-surface atmosphere. This is a common weather phenomenon. When the temperature reaches the dew point temperature (or near the dew point temperature), the water vapor in the air condenses to form fog. The difference between fog and clouds is that clouds are generated in the upper atmosphere and fog is close to the surface.

There are several different types of fog according to the cause of condensation. When the temperature is higher than the freezing point, water vapor condenses into water droplets, and when the temperature is lower than the freezing point, water vapor directly condenses into solid ice crystals, such as ice fog. Because the dew point is only affected by gas temperature and humidity, there are two main reasons for the formation of fog: first, a large increase in water vapor in the air makes the dew point temperature rise, thus forming fog, such as steam fog and frontal fog; Second, when the temperature drops below the dew point, fog is generated, such as advection fog and radiation fog.

The cause of fog

The content of water vapor in the air is limited. When water vapor reaches its maximum, it will be saturated. In the case of equal volume, the amount of water vapor contained is also related to temperature. The higher the temperature, the more water vapor in the air, and vice versa. If the ground heat is lost, the temperature drops, and the air is quite humid, part of the water vapor in the air will condense out and become many small water droplets suspended in the air layer near the ground.

Fog and clouds are caused by the drop of temperature, and fog can actually be said to be a cloud near the ground. 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.