8 layers are defined by constant trends in average air temperature (which changes with pressure and radiation), where the outer exosphere is not shown.

1. Troposphere
2. Tropopause
3. Stratosphere
4. Stratopause
5. Mesosphere
6. Mesopause
7. Thermosphere
8. Exosphere

Tropopause separates Troposphere from Stratosphere. Generally higher in summer Lower in winter.

Troposphere – temperature decreases with height. Most of our weather occurs in this layer Varies in height around the globe, but Averages of about 11 km in height.