How is dew formed?

Dew is formed because hot air is saturated when it meets an object with low temperature and condenses into small water droplets to stay on the object.

Above 0℃, the temperature at which air is saturated with water vapor due to cooling is called "dew point temperature". In warm seasons, when the ground objects are cooled by intense radiation at night, the temperature of the air in contact with the surface of the objects drops to the "dew point", and excess water vapor is precipitated. Because the temperature is above 0℃ at this time, these excess water vapor condenses into water droplets and adheres to ground objects, which is dew.

Dew, like frost, mostly appears on a clear night without wind or breeze. At the same time, objects that are prone to condensation are often objects with large surface area, rough surface and poor thermal conductivity. Sometimes, dew forms in the first half of the night, and the temperature continues to decrease in the second half of the night, which makes the dew on the object freeze. It's called frozen dew. Some people classify it as frost, but its formation process is different from frost.

Dew usually forms at night. After sunrise, the temperature rises, the dew evaporates and disappears, and it exists briefly.

Extended data:

The difference between dew and frost

1, dew, liquid formed by liquefaction of water vapor in cold environment.

2. Frost is a solid formed by condensation of water vapor in a very cold environment.

You can't think that frost is solidified by dew. First of all, they are not products of the same period. Secondly, they are formed under different conditions. Finally, the structure of ice and frost solidified by dew is different.

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