1. Composition of the Atmosphere (ATM)
The atmosphere is a mixture of gases that surrounds Earth
Earth has a unique ATM – no other planet in the solar system has an ATM with the exact mixture of gases

2. *Most Important Trace Gas - Ozone
Composition
Gases
78% Nitrogen
21% Oxygen
Remaining 1%:
Argon, Carbon Dioxide, Trace Gases*
Water Vapor (the amount of water in the air)
Dust, dirt, smoke, volcanic ash, sea salt
*Most Important Trace Gas - Ozone

3. Structure of the Atmosphere
4 Layers (5 including Exosphere)
99% of Earth’s atmosphere is within 30 km of Earth’s surface.
Changes in temperature separate the layers

4. 1. Troposphere: ~0-10km
Contains most of the mass of the ATM including water vapor
We are in this layer, where all weather occurs
Temperature decreases with increasing altitude
Tropopause: boundary between the troposphere and the stratosphere

5. 2. Stratosphere: ~10-50km
A layer made up primarily of concentrated ozone
The ozone layer is protects life on Earth by absorbing UV rays
Temperature increases with increasing altitude
Stratopause: boundary between the stratosphere and the mesosphere

6. 3. Mesosphere: ~50-80km
Temperature decreases with increasing altitude (The coldest layer in the ATM)
Where meteors tend to burn up
Mesopause: boundary between the mesosphere and the thermosphere

7. Contains only a minute portion of the ATM’s mass
4. Thermosphere: ~80km+
Contains only a minute portion of the ATM’s mass
Subdivided into exosphere and the ionosphere
Temperature increases with increasing altitude (Has the highest temperature in the ATM)
High temperatures are the result of incoming solar radiation
Auroras happen here!

8. Exosphere: Exo means outside
Outermost layer of earths ATM
Sometimes called the Ionosphere
Reaches up to 10,000 km
Temperatures are anywhere 0-1,700 C
Where the International Space Station orbits Earth

9. Layering of the ATM
Plot and connect all data points on your graph
Draw a line and label each layer, including the boundaries that are in-between