1. The Atmosphere

2. Atmosphere
A mixture of gases that surrounds a planet or moon.

3. What gases are in our atmosphere?
Nitrogen (N2) = 78%
Oxygen (O2)= 21%
Trace gases= 1%
Argon
CO2
Neon
Methane
Krypton
Hydrogen

4. What are some sources of carbon dioxide (CO2) in our atmosphere?
Burning fossil fuels releases CO2
into the atmosphere
Greenhouse Effect- CO2 and other gases act as a blanket to hold in heat close to Earth

5. What else is in our atmosphere?
Water vapor- from evaporation and transpiration (1 tree gives off 40,000 gallons of water vapor in a year!)
Solid particles (particulate matter)- dust, smoke, pollen, salt, NOX, VOX- from car exhaust, burning and volcanic eruptions

6. Ozone O3- a form of oxygen with 3 atoms of oxygen instead of 2
The layer of ozone
in the atmosphere
absorbs UV
radiation from
the sun and heats
the Earth

7. Learn more about the ozone layer:

8. Troposphere
Contains almost all of Earth’s CO2, water vapor, clouds, air pollution, weather, and life-forms.
Temperatures vary greatly
Closest to the Earth’s surface 0-15 km
Contains almost 90% of the atmosphere’s total mass!

9. Stratosphere Layer above the troposphere Extends from 15-50 km.
Low stratosphere has an average temp of -60 degrees C.
Temperature rises as altitude increases.
Contains the Ozone Layer.

10. Ozone Layer Upper layer of the Stratosphere.
Protects life on Earth by absorbing harmful ultraviolet radiation.

11. Mesosphere Middle layer of the atmosphere. Extends 50-80 km.
Upper limit for aircraft travel; lower limit for spacecraft travel.
Coldest layer

12. Thermosphere Uppermost atmospheric layer. Extends 80-500 km.
Space between particles in thermosphere is great so not much transfer of energy.
Density is LOW
Temperature increases with altitude.

13. Exosphere Absorbs harmful solar energy.
Contains electrically charged particles.
Area in which Auroras occur.

14. As an Exit Ticket for the day
On the front of your index card please write:
The layers of the atmosphere are:
, , , , ,
Please write your answer on the back of your index card.