"Rainstorm reservoir" in the sky - cumulonimbus cloud

In order to prevent drought and flood, people blocked rivers and built dams, and built large and small reservoirs on the vast land. However, people do not care about (or understand) the "natural reservoir" in the sky that does not need artificial construction, that is, cumulus clouds with different sizes, shapes, coming and going hurriedly, and changing.

In fact, clouds, especially cumulonimbus clouds, contain rich water resources. If the average water content of a cumulonimbus cloud per cubic meter is 2.5g, the total water content of a cumulonimbus cloud with a radius of 5km will reach 1.3 million cubic meters, which is equivalent to the storage capacity of a small reservoir. It has been estimated that if all the water in this "reservoir" is discharged and utilized, 300000 kilograms of rice can be produced or 300000 kilowatt hours of power can be generated. The huge dark clouds that people often see are "storm reservoirs" hanging in the sky.

The volume of cumulonimbus clouds is usually quite large. Each cumulonimbus cloud is a single precipitation unit in the rainstorm area. Although the horizontal range of each unit is only 1-20km, they can form a 100-200km wide rain belt when arranged. Cumulonimbus clouds are like mountains. When the development is intense, they extend from 0.4-1 km above the ground to more than 10 km. These "cloud mountains" exceed the height of the roof of the world.

The well-developed cumulonimbus clouds have white wisp like structures at the top, some still maintain a circular arch profile, and when they are strongly developed, they expand into horsehair or anvil like structures. The cloud bottom is chaotic, often in the shape of suspended ball, roller or arc, mostly in lead black. When cumulonimbus clouds fill the sky, people can only see the dark and chaotic cloud bottom. At this time, the sky appears very dark, which is exactly the scene of "black clouds pressing the city to urge".

The updraft in the cumulonimbus cloud is very strong, the vertical speed can reach 20-30m/s, and the maximum speed can reach 60m/s, which is larger than the wind speed of typhoon. In such a strong updraft, the water drops are constantly increasing, and the water content is also significantly increasing, with more than 10 grams per cubic meter in some areas. If the water vapor supply is very sufficient and continuous, the intense updraft will not be able to hold the increasing water droplets, so it will pour down to form a rainstorm.