13.2 NOTES The Atmosphere

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

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

Stratosphere Ozone layer at the top Temperature increases with altitude

Mesosphere Decreasing temperature with altitude Thermosphere Increasing temperature with altitude

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