Why are clouds important?
We see clouds nearly every day, but what are they? Clouds are made of millions of tiny droplets of water or ice crystals. They play an important role in the weather, because rain and snow come from them.
How do clouds form?
- 1♨️ Water vapour in the air
There is always water vapour in the air, but we cannot see it.
- 2⬆️ The air goes up
Warm air rises higher into the atmosphere, where it is colder.
- 3❄️ It cools and condenses
The water vapour cools down and condenses: it turns into tiny droplets of liquid water.
- 4☁️ A cloud is born
The droplets stick to tiny bits of dust, ice and sea salt. Millions of them together make a cloud.
Why does it rain?
Inside the cloud, the droplets and ice crystals join together and become bigger drops. When they are too heavy to float, they fall to the Earth's surface. This is precipitation. Depending on the temperature, it falls as:
Ask an adult to fill a glass with ice and water. Wait a few minutes. Can you see little drops on the outside of the glass? The water vapour in the air touched the cold glass and condensed, just like in a cloud!