Cloud introduction:

Cloud is a visible polymer floating in the air, which is composed of water droplets liquefied by water vapor in the atmosphere when it is cold or small ice crystals condensed.

Clouds are the tangible result of the huge water cycle on the earth. The sun shines on the surface of the earth, and water evaporates to form water vapor. Once the water vapor is supersaturated, water molecules will gather around the dust (condensation nucleus) in the air, and the resulting water droplets or ice crystals will scatter sunlight in all directions, which will produce the appearance of clouds.

Moreover, clouds can form various shapes, and are also divided into many kinds because of their different heights and shapes in the sky.

Related impacts:

Clouds absorb heat from the ground and radiate it back to the ground, which helps to keep the earth warm. But clouds also reflect sunlight directly back into space, which has a cooling effect. Which effect prevails depends on the shape and location of the cloud.

In the atmosphere more than ten kilometers up from the ground, the closer to the ground, the higher the temperature and the more abundant the air; The higher the altitude, the lower the temperature and the thinner the air.

On the other hand, the water surface of rivers, lakes and seas, as well as the moisture of soil, animals and plants, become water vapor with evaporation into the air. After water vapor enters the atmosphere, it becomes clouds to cause rain, or condenses into frost dew, and then returns to the ground, permeates the soil or flows into rivers, lakes and seas. Later, it will evaporate again and then condense (coagulate) and drop. It goes on and on, and it goes on and on.

Water vapor enters the lower atmosphere from the evaporation surface, where the temperature is high and there is more water vapor. If the hot and humid air is lifted, the temperature will gradually decrease, and when it reaches a certain height, the water vapor in the air will reach saturation. If the air continues to be lifted, there will be excess water vapor.

If the temperature there is higher than 0℃, the excess water vapor will liquefy into small water droplets; If the temperature is lower than 0℃, the excess water vapor condenses into small ice crystals. When these small water droplets and small ice crystals gradually increase and reach the level that human eyes can recognize, what we call clouds are formed.