Across
- 2. Natural heat produced by the Earth that can be used as an energy source.
- 4. The first National Park established in 1872
- 7. Small particles in the oceans that are formed by pollution.
- 10. This is the type of power created by dams.
- 12. Used by bats and whales to find their way around.
- 14. A park worker who needs a science degree.
- 15. a non-native organism that causes damage to the ecosystem.
Down
- 1. helps to clean air inside the home and prevents mold.
- 3. What happens to the oceans when too much Carbon is absorbed.
- 5. How we measure the intensity of sound.
- 6. a substance or thing that has a harmful impact on the environment.
- 8. A naturally occurring toxic gas that is formed when uranium breaks down.
- 9. the lowest level of park systems.
- 11. To use less of.
- 13. This was the act that Woodrow Wilson signed in 1916.
- 16. can reach sounds of 235dB in the ocean and is used to find submarines.