Across
- 6. A layer in the Earth's atmosphere that protects us from harmful rays
- 8. A type of energy that comes from sources that do not run out
- 10. The rise in Earth's average temperature over time
Down
- 1. A term used for species that are at risk of extinction
- 2. The presence of harmful substances in the environment
- 3. To process materials so they can be used again
- 4. When a species of animal or plant disappears completely
- 5. The process of cutting down trees in large areas
- 7. The usual weather conditions in a place over a long period
- 9. Coal, oil, and natural gas are examples of these energy sources