What do you know about the atmosphere (air)

what is it made up of? etc.

Atmosphere... The Earth is surrounded by a blanket of air called the atmosphere. The atmosphere is made up of various gases that act as a protective shield for the Earth and allow life to exist. Without it, we would be burned by the intense heat of the sun during the day or frozen by the very low temperatures at night.
Composition...


More than three quarters of the atmosphere is made up of nitrogen and most of the rest is oxygen. However it is the remaining 1%, a mixture of carbon dioxide, water vapour and ozone, that not only produces important weather features such as cloud and rain, but also has considerable influence on the overall climate of the Earth,through mechanisms such as the greenhouse effect and global warming. (Stay with us and we'll learn more about the changing climate in a later section!)
Pressure... The atmosphere consists of five layers, held around the planet by the force of gravity. As you move upwards through the layers, atmospheric pressure decreases rapidly with height and the air temperature also changes. It is these, more complicated, changes in temperature which are used to divide the atmosphere into the layers described below.

It's made up of 78% nitrogen 21% oxygen and 1% others (including water vapour and carbon dioxide)