What range will there be frost?

There will be frost when the ground temperature is below 0℃. When the water vapor in the air near the ground is saturated and the ground temperature is lower than 0℃, the white ice crystals directly condensed on the object when there is frost are not necessarily frost.

When the temperature is lower than the ground, the water vapor condenses into white crystals on the surface of the object. The water vapor content is less, and it is called black frost without frost; Frost damage to crops is called frost. ?

Frost is a common agricultural meteorological disaster, which occurs in winter and spring, and is mostly caused by the cold wave heading south and the temperature dropping sharply below zero degrees Celsius in a short time. After the cold wave, the weather turned from cloudy to sunny that night, which was caused by strong radiation cooling on the ground.

Extended data:

Anti-freezing method:

1, water spraying method: water spraying method can be used for small area garden plants, that is, the plants are continuously sprayed with water 1 hour before the frost comes. Spraying water can increase the humidity and temperature of the air (increase the air temperature by about 2℃), thus preventing frosting.

2. Covering method: Covering plants with straw and wheat straw can prevent the invasion of cold air, reduce heat loss and increase the temperature 1℃-2℃. In addition, for short-seedling plants, the method of soil burial can be adopted, but this method is only suitable for small areas of frost.

3. Fertilization method: apply semi-mature organic fertilizer as base fertilizer 3-4 days before frost to raise soil temperature. Warm fertilizers are commonly used, such as manure, compost and plant ash.

References:

Baidu encyclopedia-frost