The water cycle

The same water goes round and round, for ever.

Round and round

Water moves between the sea, the sky and the land in a never-ending loop. This is the water cycle. The Sun’s heat drives the whole cycle.

The water cycle has no beginning or end. It has been going on for billions of years.

Up into the sky

The Sun heats water in seas, rivers and lakes. It evaporates. Plants also give off water vapour from their leaves. This is transpiration. The water vapour rises with warm air.

In the water cycle, water also evaporates from soil, puddles and lakes, and from the leaves of trees and crops.

Clouds and rain

High in the sky the air is cold, so water vapour condenses into tiny drops. They form clouds. The drops join together and get heavier. They fall as rain, hail or snow. This is precipitation.

Raindrops form when tiny cloud droplets bump together and join. When they become too heavy to float, they fall.

Back to the sea

Rainwater runs into rivers and soaks into the ground. This is collection. Rivers carry the water back to the sea, and the cycle starts again.

In the monsoon, warm moist winds blow from the Bay of Bengal. The water vapour condenses over the land and brings heavy rain. This is the water cycle at work in Bangladesh.

What I learnt

I can describe the stages of the water cycle.
I know that the Sun drives the water cycle.