Across
- 4. is the hottest layer in the atmosphere
- 5. is the proccess of carbon naturally interchanging between the lithosphere, biosphere, hydrosphere, and atmosphere
- 6. keeps our planet the perfect temperature
- 7. of air in the thermosphere include helium, atomic nitrogen, and atomic oxygen.
- 10. is the most abundant gas in the atmosphere
- 13. begins at the earth surface.
- 14. is the most dense layer in the atmosphere
- 15. had three atmospheres
Down
- 1. is the coldest layer of the atmosphere
- 2. produced during photosynthesis
- 3. in the atmosphere can include smoke, toxic gasses, dust, ash from volcanoes, and salt.
- 8. produced during the burning of fossils fuels
- 9. coal, petroleum, and natural gas
- 11. is made up of 78% nitrogen, 21% oxygen, and smaller amounts of argon, carbon dioxide, helium, and neon.
- 12. is the layer most planes fly in