The water cycle!
Water is all over the earth. It is the life source of every living thing on the planet. If we didn’t have the water cycle we wouldn’t be able to survive.
Water can be lots of different things. It can come as vapour, ice, snow or liquid. The water cycle has 4 steps.
The sun heats water from the sea and it turns into vapour.Then it rises into the air. For example, say I spilt some water on the ground out side. Then I left it for a while. By the end of the day the water will be gone. That’s because it has turned into vapour and risen into the air.
As water vapour rises into the air, it starts to cool, turning back into a liquid. Then it condenses into clouds. Example: if you left a glass of cold water on the table and then went out for a walk, when you came back,the glass would be wet on the out side! The water hasn't leaked through the glass. When the warm air hits the cold glass, it turns back into liquid.The same thing happens in the air.
When the clouds are too heavy with water vapour, it rains. Precipitation can come in the form of rain, hail, sleet or snow. The reason it can be hail or snow is because the higher the vapour goes the colder the air gets. This freezes the vapour and it makes hail or snow. The gravity from the earth pulls the water down. Its just like a bucket of water tipping over!
When water lands back on earth, it will either soak into the ground and become groundwater or it will run across land back into lakes or oceans where the cycle starts all over again.
The water cycle is a continuous process that is happening anywhere, anytime. Without it no life would exist on our planet.