Traditional Culture Encyclopedia - Weather forecast - How is dew formed?

How is dew formed?

According to meteorologist Guan Jianhua, dew actually exists all year round, only in autumn.

Guan Jianhua introduced that on a clear and cloudless night, the ground heat dissipates quickly and the ground temperature drops quickly. When the temperature drops, the ability of air to contain water vapor decreases, and the water vapor in the lower atmosphere adheres to grass, leaves, etc. and condenses into water droplets, that is, dew.

The formation of dew is conditional, and it can only be formed under the weather conditions of stable atmosphere, low wind, clear sky and local cloudy ground heat loss.

If there are clouds in the sky at night, the ground is like a quilt. After the heat hits the clouds, part of it turns back to the ground and the other part is absorbed by the clouds. This part of the heat absorbed by the clouds will slowly radiate to the ground in the later stage, and it is difficult for the ground temperature to drop and dew to appear.

In addition, if the wind is strong at night, the wind makes the upper and lower air communicate, which increases the temperature of the air near the ground and makes the water vapor diffuse, so it is difficult to form dew.

Dew is good for crops. Dew, like rain, can moisten the soil and help plants grow.