Water

All living things on earth need water in order to survive.

When the sun shines onto areas of water, the water warms up and rises into the air as a gas called water vapour. This process is called evaporation. When water vapour in the air cools, it changes back into droplets of water. The tiny water droplets gather together to make a cloud. Eventually, the water droplets in the cloud fall to earth as rain or snow.

Rain and water from melted snow runs down into lakes and rivers, into drains and eventually into the ocean. Water evaporates and becomes water vapour and so on. This is called the water cycle because it goes on continuously: water never stops moving.
Go here for an animation of the water cycle http://www.epa.gov/safewater/kids/flash/flash_watercycle.html

Evaporation also occurs from plants. Water from the surface of leaves warms and changes into water vapour.

The Water Cycle: The sun evaporates water. Water vapour forms clouds.
Rain or snow falls and ends up in lakes, rivers and the seas.

Rivers, streams and most lakes are fresh water.

Most of the water on earth is in the oceans, and this is salt water. The salt comes from rocks that the water has washed over in rivers and streams on its way into the sea.

Large dams are built to collect rain water and other fresh water for human use. These are called reservoirs.

Some rivers are frozen. They are called glaciers
(say glay-see-ers). Glaciers are frozen fresh water.

Sometimes a huge mass of glacier breaks away and floats out into the sea. It is called an iceberg. An iceberg is frozen fresh water.

Even though it is frozen all the time, Antarctica is the driest of all the continents.

Australia is the second driest continent. In Australia there is a combination of low rainfall and a very high evaporation rate of water because of the sunshine. Even though they live on such a dry continent, Australians use a lot of water.

Some more Facts about water

75 % of the Earth is covered with water.

97 % of Earth's water is in the oceans.

Only 3 % of the Earth's water can be used as drinking water.

75 % of the world's fresh water is frozen in the polar ice caps.

Water expands (takes up more space) when it freezes.

Raindrops are not tear shaped. The shape is more like that of a hamburger bun as they fall from clouds.

A person can live without food for more than a month but can only live without water for about one week.

Some of the main causes of water pollution are: oil spills, fertilizer and agricultural run-off, sewage, stormwater, and industrial wastes.

Water boils at 212 degrees Fahrenheit or 100 degrees Celsius.

Water freezes at 32 degrees Fahrenheit or 0 degrees Celsius.

About two thirds of the human body is water and 70% of the skin is water.
Read more about water and your body here

About 19 million megalitres of fresh water is used in Australia each year. Most of this water (about 70%) is used for agriculture, especially irrigation, to grow food and other products consumed in Australia and exported. Households use about 8%.

To find out about:

Did you know?
Water is used to make electricity. It is called hydro-electricity. Go here for the kidcyber page about hydro-electricity

Acknowledge this source in your bibliography like this:
Thomas & Sydenham, Water. [Online] www.kidcyber.com.au (2008)

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