1. Unit 10/ Day 1 Notes Have a book open to page 4 please.
The Atmosphere!
Unit 10/ Day 1 Notes
Have a book open to page 4 please.

2. Do you know?
Before we begin, talk these questions over with your group mates:
Have you ever heard of the atmosphere before? If so… How? Where?
What is the common gas in the atmosphere?
Does air contain anything other than gases?

3. “A mixture of gases that surrounds the Earth”.
What is the atmosphere?
“A mixture of gases that surrounds the Earth”.
A protection shield to keep you safe from the sun’s harmful rays.
5 layers: troposphere, stratosphere, mesosphere, thermosphere/ionosphere, exosphere
A mixture of different pressures and temperatures throughout the layers.
-sphere means “ball,” which suggests that each layer surrounds our planet like a hallow ball.

4. Composition of the Atmosphere
Atmosphere is made up of gases like nitrogen, oxygen, and carbon dioxide.
Nitrogen: 78%
Oxygen: 21%
“Other”: 1%
Nitrogen is the most abundant gas within our atmosphere. It is released when dead plants/animals break down. It is also released when volcanoes erupt.
Oxygen is the second most common gas and is created by phytoplankton and plants (photosynthesis).
Other gases within our atmosphere include water vapor, carbon dioxide, argon, and methane (cow farts ).

5. How does the atmosphere look?
An invisible protective shield that surrounds our planet.
The layers are defined by changes in temperature.

6. Troposphere Located at sea-level, this is the layer we live in.
Temperature decreases as altitude increases.
The densest atmospheric layer
Almost all the Earth’s activity occurs here (clouds, pollution, weather, life-forms, etc.)
Tropo- means “turning,” which is where gases turn and mix.

7. Stratosphere
This layer lies above the troposphere and is home to the ozone layer.
The ozone layer is the protection from harmful UV radiation.
Contains little moisture, and air is thin.
Temperature increases as altitude increases.
Strato- means layer since the gases do not mix very much.

8. Mesosphere
3rd layer in our atmosphere (the middle layer) and also known as the coldest layer.
Temperature decreases as altitude increases.
Most meteors burn up in this layer fromspace.

9. Thermosphere Known as “The Edge of the Atmosphere”
Temperature increases as altitude increases.
Known for temperatures being 1,000 degrees Celsius or higher, making this the hottest layer.
Has a very low density and particles in this layer do not transfer much thermal energy.

10. Ionosphere Home of the Auroras, also known as the “northern lights.”
Auroras are shimmering lights created by electrically charged particles called ions.
This layer reflects AM radio waves, causing radio waves to bounce off this layer and get sent back to Earth.

11. There are 3 total spheres on Earth:
Other facts
There are 3 total spheres on Earth:
Atmosphere
(air)
Lithosphere
(land)
Hydrosphere
(water)

12. Unit 10/ Day 2 Notes Have your book open to page 5 please.
The Atmosphere!
Unit 10/ Day 2 Notes Have your book open to page 5 please.

13. Properties of Air
Density is the amount of mass in a given volume of air.
As the volume of air increases, the density decreases.
Pressure is the force pushing on an area or surface.
As density/volume/temperature increase, pressure increases.
- Air molecules seek balance pressure: to balance or equalize pressure, the pressure on the inside must equal the pressure outside an object.

14. Properties of Air continued.
Mass is the amount of matter in something.
Altitude is when air pressure decreases as altitude increases.
As air pressure decreases, so does density.

15. Do you know… What does being at sea-level mean?
What happens to air pressure when you are at sea-level?
What happens to air pressure when you are below sea-level?
What happens to air pressure when you are above sea-level?