Across
- 3. a prolonged period of abnormally low rainfall
- 7. converting waste into reusable material
- 8. a condition where the number of existing human population exceeds the carrying capacity of the Earth
- 9. capable of being decomposed by bacteria or other living organisms
- 10. a type of air pollution
- 11. the amount of carbon dioxide released into the atmosphere as a result of the activities of a particular individual, organization, or community
- 13. a natural resource or source of energy that is not depleted by use, such as water, wind, or solar power
- 14. the gases that can trap heat
- 16. an area of land with a group of energy-producing windmills or wind turbines
- 18. a region of the Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation
- 19. a rain or any other form of precipitation that has elevated levels of hydrogen ions (low pH)
Down
- 1. a gradual increase in the overall temperature of the Earth's atmosphere
- 2. a species of animal or plant that is seriously at risk of extinction
- 4. the release of a liquid petroleum hydrocarbon into the environment, especially the marine ecosystem, due to human activity
- 5. the process of replanting an area with trees
- 6. a colorless gas that people and animals release when they breathe out
- 12. chemical compounds that are used to kill insects, rodents, fungi and unwanted plants
- 15. the sun is the main source of ... rays
- 17. a vehicle that combines two or more sources of power