Rain is part of the water cycle. This means that water runs through different stages before it turns to rain.
The water cycle
- It rains: Water falls onto the ground.
- Water flows into the ground (for example, into sand, rubble, fields). Trees and plants suck up this water to grow leaves and flowers.
- Eventually the water that is in the ground an in the leaves turns into steam: It evaporates. This happens faster when the ground warms up quickly after a rainfall.
- The steam rises from the ground to the sky and turns into clouds.
- The clouds get heavier and heavier. The water gathers in them as steam that consists of vey little drops. When there is lots of evaporated water, these little drops join together to form larger water drops.
- Sooner or later the water drops get too heavy and fall out of the cloud - it rains again.
And now the cycle starts all over again.
Create your own rain
You can even create your own rain! All you need is a small glass, a big jar, a small twig with leaves, and a bit of oil.
Take the twig with the leaves and put it in the glass. Pour some water into the glass (it should be half full). Pour a little bit of oil onto the surface of the water. The water should be fully covered by the oil. Put the big jar over the glass with the twig and expose it to sunlight. After a while littledroplets of water form on the sides of the jar.
This happens because the twig sucks up the water into it's leaves and the water evaporates. The evaporated steam at first stays in the air, but after a while the air is so full of water that it cannot take any more, it is "saturated". The water now forms into drops, it "condensates". The oil on the surface of the water is there in order to hinder the water itself from evaporating - the water on the sides of the jars is indeed only evaporated and condensated water from the leaves!
Draughts and Floods
If there is not enough rain, the ground gets too dry and it is hard to grow any plants on it. This is called a draught. People living in areas with not enough rain often suffer from hunger because they don't get enough food because it is so dry.
But if there too much rain, the ground gets swamped with water. The ground is already so full of water that it cannot take any more. Then the water stays on top of the ground and a flood is forming. A flood will also damage the ground and the plants in it and if the flood is very strong it might even damage buildings and poeple. (also see The London Flood)
So both too much and too littlr rain can be very harmful.
Europe usually has no major floods or draughts. But currently there is a small draught in the South East of the United Kingdom because there is not as much rain as usual. This means that people have to save money, for example gardeners are not allowed to use hose pipes anymore because this will waste too much water.
Check up-to-date weather information for London
