The Earth

From space the Earth looks blue, white and brown. There are 4 parts

• the atmosphere is the air that surrounds the Earth.

Air is mainly nitrogen and oxigen. There are also small quantities of carbon dioxide, ozone and water vapour.

The atmosphere has got layers:      

Exosphere - The last layer and   the thinnest.  Thermosphere - The thermosphere is next and   the air is very thin here. Temperatures can get extremely hot in the thermosphere. Mesosphere - This is where most meteors burn up upon entry. The coldest place on Earth is at the top of the mesosphere. Stratosphere - it gets warmer the further away you get from the Earth. There is a thin layer of ozone in the upper stratosphere, This is called the  ozone layer. Troposphere - The troposphere is the layer next to the ground or surface of the Earth. This is where we live and even where planes fly.

• the hydrosphere is the water on Earth (oceans, lakes, rivers, ice and snow in the poles and mountains)

The water cycle

It is the constant circulation of water between the sea, the atmosphere and land.

1. Water evaporates because of heat from the Sun. It becomes water vapour.
2. Water vapour rises and condenses into drops of water. The water drops form clouds.
3. Water falls from clouds as rain: precipitation. When it is very cold, water solidifies and falls as snow.
4. Water flows over the land and filters into it. It forms rivers and lakes.
5. The water returns to the sea or evaporates. The water cycle starts again.

Click here to learn more things about THE WATER CYCLE.

• the biosphere is all the living things on Earth.

• the geosphere or lithosphere is the ball of rock. It has 3 layers

• The crust is made up of solid materials: rocks. Rocks are made up of minerals.

• The mantle is very hot. In some parts there is magma.

• The core is extremely hot.

ACTIVITIES

Water and air activities

Earth system cards

SONGS

Water cycle rap