Why does it rain?
2、? The basic process of rain formation is that the water vapor in the air condenses at high altitude to form small water droplets or ice crystals, which collide with each other and become larger and larger. When the air can't hold up, it will fall down. When the low-altitude temperature is higher than 0℃, it is rain. ?
3. Clouds composed of liquid water droplets (including supercooled water droplets) are called water clouds. If the conditions for cloud droplets to grow into raindrops are met in the water cloud, and the raindrops have a certain falling speed, then it is rain or Mao Mao rain that falls. Clouds composed of ice crystals are called ice cloud, and clouds composed of water droplets (mainly supercooled water droplets) and ice crystals are called mixed clouds. Ice crystals or snowflakes falling from ice cloud or mixed clouds fall into the gas layer above 0℃, and after melting, they also fall to the ground as raindrops, forming rainfall.
4、? In the process of rain formation, large water droplets play an important role. When the radius of water droplets increases to 2-3 mm, it is difficult to maintain such a large water droplet by the attraction between water molecules, and it is easy to be split by the impact of airflow on the way down, through a "chain reaction." Make big water droplets fall, and small water droplets continue to exist, forming new big water droplets. This is an important reason for the formation of rain in water clouds and mixed clouds with strong updraft.