When you look up at the sky and see some big, heavy clouds, you might think it looks like rain.
We often tend to think that this is all it takes to produce rain. But actually rain is the result of a long and a complicated process.
It takes the combined influences of the sun, the earth and the atmosphere to produce rain.
The process starts when the earth is heated by the sun. This causes the water in the earth's oceans, lakes and streams, and in dump soil, to turn into water vapour. The water vapour then mixes with the air. This process is called evaporation.
Now rising warm air carries the water vapour into the atmosphere. Here it expands and cools. As this happens, the warm air gives up some of its load of invisible water vapour, and this forms clouds. This process is called condensation.
Inside the cloud, the tiny droplets gradually become larger and larger as they collect more moisture. Finally, the drops become so large that they can no longer be held up by the air currents, and they fall to the ground as rain.
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