1. Chapter 4.1- Earth’s Atmosphere Pages 90-97

2. Earth’s Atmosphere Atmosphere- a thin protective layer of air that surrounds the Earth and makes life possible Atmospheric Gases: 78% Nitrogen, 21% Oxygen, 1% other gases Solids: dust, salt, pollen Liquids: water

3. Troposphere Lowest layer Where I live Weather occurs here Contains 99% of the water vapor found in the atmosphere & 75% of atmospheric gases Extends 10 km above Earth’s surface (6.2 miles) Higher you go the colder it gets

4. Stratosphere 10-50 km above Earth (6 - 31 miles) OZONE LAYER that protects us from sun’s UV rays is found here Planes and jets fly here The higher you go the warmer it gets because of the ozone layer

5. Mesosphere 50-85 km above Earth (31 – 53 miles) Meteors burn up in this layer b/c of friction with air particles (called shooting stars) Temperature decrease as you go higher in the mesosphere (COLDEST LAYER)

6. Thermosphere thickest layer of the atmosphere 85 - 500 km above the earth's surface (53 – 310 miles) very high temperatures -90 - 2000C auroras, northern lights Ionosphere – located here, a layer of electrically charged gas particles which allows radio waves to travel across the country

7. Exosphere outermost layer of the atmosphere 500 km - outer space (310 miles & beyond) few molecules exist in exosphere and thermosphere they have extremely high energy & temps because 1st layer to receive the suns energy space shuttle and satellites so few molecules that the wings of the space shuttle are useless it uses rocket launchers Jason-2 satellite carries tools & sensors to help study ocean.

8. “pauses” of the atmosphere -boundaries of the layers 4 pauses that occur AFTER that layer 1. Tropopause 2. Stratopause 3. Mesopause 4. Thermopause

9. Temperature Differences in the Atmosphere The layers of the atmosphere are broken up based upon differences in temperature. Let’s practice reading this graph… 1. What layer does the temperature reach -90 o C 2. If you are at an altitude of 70km, what layer would you be in? 3. What layers does the temperature decrease with altitude? 4. What layers does the temperature increase with altitude?