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The water cycle
How the same water keeps moving between the sea, the sky and the land.
18 October 2026
Water never stays in one place. The same water moves, again and again, between the sea, the sky and the land. This journey is called the water cycle.
It begins with the sun. Heat from the sun warms the surface of the sea, and some of the water turns into an invisible gas: water vapour. Plants give off water vapour from their leaves, too.
Warm, moist air rises. As it rises, it cools, and the vapour turns back into tiny droplets of water. Countless droplets together make a cloud.
Inside the cloud, the droplets join and grow. When they become too heavy to float, they fall as rain, or as snow where the air is cold.
On land, some of the water runs into streams and rivers. Some soaks into the ground and is stored there. Sooner or later, most of it reaches the sea again.
And there, the sun warms it once more. The cycle never stops.