1. AtmosphereAtmosphere

2. Importance: 1) balance between heat absorbed from Sun and amount that escapes back (extreme temperatures) 2) protects Earth from Sun’s harmful rays

3. Early Atmosphere: Volcanoes produced nitrogen and carbon dioxide and little oxygen 2 billion years ago simple organisms started making oxygen

4. Early Atmosphere: Ozone layer formed protecting the Earth from Sun’s rays Green plants then released more oxygen

5. Makeup of Atmosphere: Nitrogen 78% Oxygen 21% Argon Carbon dioxide1% Other gases and water vapor 1) Gases

7. Gases Atmosphere changing because of pollutants increasing CO 2 Pollutants mix with water droplets & chemicals = smog

8. 2 Solids Dust Salt Pollen

9. 3 Liquids Water droplets Droplets from volcanoes

11. Troposphere All life Weather occurs Jets fly here Lowest layer

12. Troposphere Air pressure greatest near surface decreases as you go up Contains ¾ (75%) of atmospheric gases Nearly all water vapor (99%) Temperature decreases

13. Stratosphere Jet Stream Jets fly here to avoid storms Temperature increases

14. Stratosphere Ozone layer (O₃) Protects Earth from Sun’s harmful rays (UV) Molecules of ozone absorb Sun’s energy so as altitude increases; the temperature increases

15. Mesophere Meteor showers (shooting stars) Temperature decreases

16. Thermosphere Highest temperature 1 st to receive sun’s rays  few molecules 2 parts: ionosphere & exosphere

17. Ionosphere Temperatures increase reflects AM radio waves at night

18. Ionosphere Northern lights

19. Exosphere Space shuttle Satellites International Space Station Temperature increases

20. Importance of Ozone Life depends on ozone 19-48 km above Earth’s surface Made of 3 atoms of oxygen Absorbs ultraviolet radiation (UV rays)

21. Importance of Ozone Air pollutants destroying ozone CFC’s (chlorofluorocarbons)in fridges, air conditioners, aerosol Sprays, & some foam packing

22. Chlorine is broken off CFCs by UV rays into regular oxygen that can’t absorb UV rays

23. creates a hole in ozone over Antarctica increase of UV rays kills life and causes skin cancer