The following processes make up the water cycle: GROUNDWATER - MAKING THE INVISIBLE VISIBLE

The world’s water moves between the sea, air and land. During the cycle it changes from one state – sold, liquid or gas – to another. The water cycle is powered by energy from the sun, which evaporates water from the land and sea.

EVAPORATION

– occurs when the sun’s heat causes water from the sea, lakes, rivers and other wet surfaces on land to turn into gas or steam. Have you ever seen steam rising from the tar road after a shower of rain? The tar road is hot due to the sun’s heat. Suddenly there is a shower of rain and as the rain falls on the hot tar you can see the steam rising as the rain drops evaporate.

CONDENSATION

– is when a gas turns back into a liquid. Water vapour in the air gets cold and changes into a liquid, forming clouds. You can see it for yourself … take an ice-cold softdrink out of the fridge on a hot day and watch how tiny little droplets form on the outside of the can. Water vapour in the air turns back to liquid when it comes into contact with the cold can.

TRANSPIRATION

– is the loss of water from land plants back into the atmosphere. Water is channelled from leaves and roots into the soil and then evaporated back into the atmosphere.

Water can be stored in ice caps and glaciers for thousands of years before eventually melting and re-entering the cycle.

PRECIPITATION

– is a form of water that falls from the sky as rain, hail, snow or sleet. Precipitation is how water in the air returns to land to continue the water cycle.

PERCOLATION

– is the movement of water through soil and rocks as ground water. It begins with water soaking into the ground known as infiltration. Water can take from hours to hundreds of years to gather in layers of rock underground called aquifers.

Almost all of the liquid freshwater in the world is groundwater. We need to work together to save this precious resource.