Thursday, 3 May 2007

Year 7 - The Water Cycle

What is the water cycle?

The water cycle describes how the water on this earth circulates or goes around and around from the oceans to the atmosphere to the land and back to the oceans again. This means that the water that falls on you as rain has fallen a million times before.

Key Terms:

Evaporation - Transfer of water from the sea to the air.

Transpiration - The transfer of water from plants to the air as gas.

Condensation - Water vapour changes back to water and forms as water droplets which are visible as clouds.

Precipitation - Moisture falls to the earth (rain, snow, hail)

Surface Run-Off - Water which lies on top of, or flows over, the ground.

Infiltration - The movement of water from the surface of the ground into the soil.

Groundwater - Water stored in rocks.

Hydrology - The study of water.

The water cycle helps us to understand our weather systems and how precipitation supplies our rainfall and how the sun affects the weather that we get in the UK.

Follow-up your interest in the water cycle by using the websites below:

Kidzone - Water
National Marine Aquarium website - The water cycle
Met Office website

Animation courtesy of