Across
- 4. scale tree removal (9 letters)
- 6. factor in smog and acid rain (2 words, 8 letters)
- 7. of energy derived from the sun (5 letters)
- 8. geological movements caused by the Earth's tectonic forces, often natural disasters (10 letters)
Down
- 1. home or environment of an animal, plant, or other organism (7 letters)
- 2. of converting waste into reusable material (8 letters)
- 3. to plastic (5 letters)
- 5. most abundant greenhouse gas (7 letters)