1. The surrounding air of the Earth
Atmosphere
The surrounding air of the Earth

2. Atmosphere The layer of gases that surround the Earth.
thicker at the innermost radius around Earth and it becomes thinner towards outer space.

3. Layers of the atmosphere
There are 4 layers in the atmosphere
They are the troposphere, stratosphere, mesosphere, thermosphere which contains the ionosphere and exosphere

4. Troposphere(0-10km)
This is the layer that is closest to the surface of the earth
Temperature decreases with altitude
This is the layer where life exists; where weather occurs.

5. Stratosphere(10-25km) This layer sits on top of the troposphere
This layer contains the ozone layer, O3 which protects us from harmful UV rays which can damage cells

6. Mesosphere(25-85km) This layer is above the stratosphere
Temperature decreases with altitude
This is where we see "falling stars" – meteors burning up as they fall to Earth

7. Thermosphere(85-400km) This is the highest layer of the atmosphere
The interesting facts about the atmosphere is that the temperature in the thermosphere increases and it can be higher than 2732º F (1,500º C).

9. Ionosphere(85-200km)
the northern lights (aurora borealis) occur because free electrons and ions tend to recombine in this layer
An increase in solar activity can disturb the radio communication as it increases the number of charged particles in the ionosphere.

11. Composition of Air
There are many different types of gases in the atmosphere
They include nitrogen, oxygen, argon, carbon dioxide and other noble gasses
The gas that is most abundant is nitrogen