1. 13.2 NOTES The Atmosphere

2. A.1 Structure of the Atmosphere
The Earth’s atmosphere can be divided into four layers that are divided based on if the temperature is increasing or decreasing, as well as altitude

3. Troposphere
closest to us, where weather occurs
Temperature decreased with altitude

4. Stratosphere
Ozone layer at the top
Temperature increases with altitude

5. Mesosphere
Decreasing temperature with altitude
Thermosphere
Increasing temperature with altitude

7. The composition of the troposphere is very consistent
The majority of the atmosphere is made up of nitrogen (78.1%) and oxygen (21.0%)
Trace gases that make up the remaining < 1% include
Argon, CO2, Neon, NH3 (ammonia), Helium, CH4 , Krypton
At any time, the atmosphere may contain up to 5% water vapor
humidity is amount of water vapor in the air