Why are the clouds in the sky black before the rain? Thanks 20

Clouds are divided into cirrus, cirrocumulus, cirrostratus, cumulonimbus, cumulonimbus, etc., and it is cumulonimbus that can produce rain, and the height of cumulonimbus is the lowest among all kinds of clouds, and it is difficult for the light of the sun and moon to transmit through, and it looks very dark.

Why are the dark clouds "black"? The example of a summer white cloud turning into a dark cloud in an instant is the most illustrative. In this abrupt change, the total amount of water remains basically unchanged, and the angle of sunlight projection is basically unchanged, and the conspicuous change is "from white to black".

This kind of thing always happens when a thunderstorm is approaching, which shows that the "white to black" is the result of the water droplets "from small to large". The dark cloud is not a "black cloud" without brightness, but bright, and its scattered light is actually still white light, which is no different from the scattered light of white clouds in terms of spectrum, because large and small water droplets are colorless transparent ball lenses for visible light, and the color of the scattered light is determined by the color of the incident light. Once this is clear, we can use "brightness" to make a quantitative comparison between white clouds and dark clouds. `

Actually, it's not that the clouds are blackened, the clouds are still the same color, but when it is going to rain, the density of the clouds is relatively large, and many clouds are clustered together, so that the overlap will look black.

Because the light is blocked, the sun's rays are blocked, so the clouds will be black.

That's because there are a lot of raindrops, they will block out the sun, and there will also be dark clouds, so it will be black.

It's not that the clouds are black, it's that when it rains, the clouds are thicker, and the rays that block the sun appear darker.

Because the dark clouds produced when it rains are very dense and there are many impurities in the air, the clouds will turn black.

It is caused by vapor condensation. It is also determined because of the thickness. So when it rains, the clouds get darker and darker.

The "black clouds" we usually see on rainy days are commonly referred to as dark clouds, and the professional term is called cumulonimbus clouds. It's the water vapor in the air that gets cold and forms small droplets, or Xiaoice crystals, and that's what we see on the ground, because they're thick, so they block most of the light, so they look darker, and that's why we call them dark clouds.

And because the dark clouds themselves cannot carry such a heavy object, just imagine that tens of thousands of tons of water in the sky, completely supported by clouds, is obviously unrealistic, so they talked about it. Because there is less moisture in the clouds after the rain, it cannot block the sunlight, so it becomes relatively white. ,6,The clouds are very thick and completely block the sunlight without sunlight and it is dark,2,There are usually many kinds of dark clouds.

Take cumulonimbus clouds, for example, where there are too many small water droplets in the clouds, which cause the continuous refraction and blocking of the sun's rays when the light shines through the clouds. Naturally, the light is dim. Dark clouds can also be said to be shadows of clouds

Rain, snow, hail in the process of formation in the air. All need to have solid condensation nuclei, generally dust, etc. In this way, when the temperature is lowered to a certain level, water vapor adheres to its surface and is formed.

When the number reaches a certain level, a cumulonimbus cloud is formed. The clouds thickened, and of course the color deepened...2, the cumulonimbus cloud is very thick, blocking the sunlight, so it is a black cloud, 1, the cloud is very thick and blocking the sunlight What we see is the shadow on the back of the cloud So it feels jet black, 1,

Because the clouds on a rainy day are thick and dense, it is difficult for light to penetrate, so it is dark, and I really help you look forward to it.

When it rains, clouds turn black because the droplets of saturated steam and supersaturated steam in the white clouds change color as the droplets become larger and larger. There are many types of clouds, such as stratiform clouds that cover the sky, isolated cumuliform clouds, and undulating clouds. Very thick stratiform clouds, or cumulonimbus clouds, where the light of the sun and moon are difficult to penetrate, makes the clouds appear very dark.

Dark clouds: In summer, surface water evaporates rapidly under the scorching sun, making the air more and more humid; The temperature at high altitude is lower than the surface temperature, so water vapor first reaches saturation and supersaturation at high altitude. There will always be some dust in the high altitude, which becomes the center of condensation, so that the saturated steam and supersaturated steam condense into fine droplets; When the droplets are dense enough, they become white clouds visible to the naked eye; The droplets grew larger and larger, and the white clouds became dark clouds; The droplets in the clouds continue to grow in size, and they become raindrops; After the rain, the humidity of the air becomes smaller, the water vapor returns to an unsaturated state, and the small water droplets in the dark clouds begin to evaporate, and the volume becomes smaller and smaller, so that the dark clouds become white clouds; The fog droplets in the white clouds continue to evaporate, and once they are all vaporized, the white clouds disappear and the blue sky is revealed.

When it rains under the clouds in the sky, it may rain in the clouds above. This is because the process of rainwater formation involves the water cycle in the atmosphere, in which clouds play an important role.

In the atmosphere, water vapor cools and condenses as the air rises, forming small water droplets or ice crystals that condense into clouds. When water droplets or ice crystals in clouds are large enough, they fall due to gravity and become rain or other forms of precipitation. Therefore, when there is precipitation in the lower part of the cloud, there is also a chance that the water droplets or ice crystals in the upper cloud layer will gradually increase, eventually forming precipitation.

In addition, precipitation from the upper clouds can also evaporate or melt during the fall, causing the precipitation to disappear or be converted into other forms of precipitation, such as snow or ice particles. As a result, there is a complex water cycle and interaction between the different cloud layers in the sky, leading to the possibility of mutual influence of precipitation between them.

The reason for rain beneath the clouds in the sky is that moist air is heated up by natural heat sources such as the sun, mountains, and lakes, and is cooled and condensed to form clouds. Whereas, clouds contain water vapor, and when the humidity reaches a certain level, the water vapor will condense into water droplets or crystals, forming precipitation.

Therefore, when it rains, the air below the clouds contains a lot of precipitation, while the air above the clouds is drier

Because when it rains, the fog droplets condensed by saturated steam and supersaturated steam in the white clouds will become larger and larger, and when they reach a certain content, they will change the color of the clouds, which is a normal natural phenomenon, and the clouds that change color are called "dark clouds".

There are many types of clouds, such as stratiform clouds that cover the sky, isolated cumuliform clouds, and undulating clouds. Very thick stratiform clouds, or cumulonimbus clouds, where the light of the sun and moon are difficult to penetrate, makes the clouds appear very dark. The slightly thinner stratiform and undulating clouds appear gray, especially the undulating clouds, with more grayish colors at the edges of the clouds.