Snow is precipitation composed of a large number of white opaque ice crystals (snow crystals) and their polymers (snow masses).
The water on the earth is constantly circulating. The water in the ocean and on the ground is heated and evaporated into the sky. The water vapor moves to other places with the wind. When they encounter cold air, they form precipitation and return to the earth's surface. There are two kinds of precipitation: one is liquid precipitation, which is rain; The other is solid precipitation, which is snow or hail.
Snow crystals are mainly increased by condensation in clouds. First of all, ice crystals are produced by ice nucleation in cold clouds. They grow into snow crystals through condensation (ice crystal process), and then they can grow by colliding with supercooled water droplets.
Extended data:
Conditions for the formation of snow:
1, the atmosphere needs to contain cold ice crystal nuclei.
2, need to have enough water vapor. The temperature should be lower than 3.0℃ (freezing point). If the cold air is quite strong and carries moisture, it can snow at the temperature of 1℃ to 10℃. ?
3. The climate zone belongs to the middle latitude to the high latitude (that is, the area south of the Tropic of Cancer/north of the Tropic of Cancer) and there are opportunities for snowfall. If there are some mountains or plateaus with an altitude of more than 2000 meters in low latitudes, there is also a chance.
4. Ocean airflow will also indirectly affect the probability of snow in this area. If there are more warm currents in high latitudes, it will reduce the chance of snow in this area (such as Honshu to Kyushu, Japan).
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