The Atmosphere!

1. 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. 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. • 5layers: 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. Other facts • There are 3 total spheres on Earth: • Atmosphere • (air) • Lithosphere • (land) • Hydrosphere • (water)

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

13. Properties of Air • Densityis the amount of mass in a given volume of air. • As the volume of air increases, the density decreases. • Pressureis 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?