Do frosts occur more often on cloudy nights? Why?

Because the atmosphere is too weak because of the clear sky. When sunlight transmits heat to the earth, the ground can reflect a part of the heat into the universe, which is called ground radiation, and the reflection ability of clouds is very strong. On a clear night, this effect is quite weak, so a clear night will feel colder than a cloudy night, especially in the morning if you find that if the previous night was cloudy, it would not be cold at all.

In the opposite way, the clouds return some of the solar radiation back to space, so the ground receives less heat, so cloudy days are colder than clear days. In the middle latitudes of China, where the four seasons are distinct, late autumn to early spring of the following year is the time before and after the beginning and end of winter, and the temperature at night can generally drop below 0. In the clear night, because there is no cloud, the ground heat is dissipated quickly, and in the first half of the night, because the ground stores more heat during the day, the temperature is generally not easy to drop below 0.

Especially in the second half of the night and before dawn, the ground emits a lot of heat, and the heat that obtains atmospheric radiation compensation is very little, the temperature drops very quickly, when the temperature drops below 0, the water vapor in the air near the ground adheres to the earth's clods, stones, leaves, grass and trees, tiles and other objects of the low house, and condenses into the hoarfrost of ice crystals. Therefore, there is an agricultural proverb in our country that "frost sees sunny days". If the temperature drops below zero and there is a lack of moisture near the ground, it will not form hoarfrost, but the crops will still be frost damaged, which farmers call "black frost".

If the night is cloudy and cloudy, the inverse radiation of the cloud can continuously compensate for the loss of ground heat, and the temperature is not easy to drop below 0, so there will be no frost. So frosts generally occur on clear nights.

No. When the ambient temperature is not too low, frosts generally occur on clear nights. Because the temperature drops little and slowly on cloudy nights (infrared reflection and insulation of the clouds), it is not easy to form the low temperature conditions caused by frost.

Of course, in the depths of winter, when it is very humid and the temperature is very low, frost can occur at any time.

Because when frost is formed, the requirements for ambient temperature are relatively high, and this kind of ambient temperature must reach a relatively low time before frost can really form. So if it is in a clear night, there is no white clouds at this time, and the ground stores enough heat during the day, then when there is no sun at night, the heat on the ground will be dissipated very quickly, and there is no cloud obstruction, and the heat on the ground will be dissipated very quickly. However, if there are clouds, then the weather will be in a relatively cloudy state, and the heat on the ground cannot be quickly lost through the clouds, so the temperature of the ground will be in a relatively high state, and it is difficult to freeze.

The existence of these hoarfrost is generally due to the low heat at night and the noise is at 0 degrees, or when it is around 0 degrees, if it is higher than such a temperature, even if there is more water vapor on the ground, it will not let them easily solidify into hoarfrost. But if the temperature reaches such a level, but there is not enough moisture, there is no way to successfully condense into hoarfrost. However, in the respiration of plants, water is formed.

In this state at night, plants can only respire, but cannot photosynthesize, so there is no way for this water to be fully converted into other energy, and the excess water will be emitted with the respiration of plants.

Although the moisture they emit is relatively lacking, if this moisture is placed in front of nature, this moisture can be said to be a relatively large existence, and it is very easy for people to use this moisture to condense frost. But keep it clear, because this will allow the night temperature to drop to a suitable condensation temperature.

Therefore, this is the reason why frosts in our country mostly occur in clear nights, and there is no way to have frost in the general cloudy nights.