Across
- 3. ___ energy: direct energy from the sun
- 5. ___ dioxide is what we exhale
- 6. historical evidence like ___ can help us to see what climate was like in a particular place at a particular time
- 9. cutting trees down
- 10. the ___ effect
- 11. ___ fuels - we burn these to create energy
Down
- 1. the average weather over a long period of time, usually 30 years
- 2. the mixture of gases surrounding the Earth
- 4. the process that occurs in living green plants where carbon dioxide is converted to oxygen
- 7. ___ rings can be used to tell how warm/cold climate was over time
- 8. the greenhouse gas that comes from organisms, eg. cow's flatulence