environment

2. a gradual increase in world temperatures caused by gases such as carbon dioxide
6. produced when people drive their vehicles for personal use
7. someone who publicly supports something.
10. causing little or no damage to the environment and therefore able to continue for a long time.
11. fuels, such as gas, coal, and oil, that were formed underground from plant and animal remains millions of years ago
12. comes from industries production of goods and services that we consume
13. energy is produced using the sun, wind, etc., or from crops, rather than using fuels such as oil or coal.

1. an increase in the amount of carbon dioxide and other gases in the atmosphere is believed to be the cause of a gradual warming of the surface of the earth
3. changes in the world's weather, that it is believed to be getting warmer as a result of human activity
4. a gas that causes the greenhouse effect, especially carbon dioxide
5. a mixture of gases that surrounds any planet.
8. a person who doubts the truth or value of an idea or belief.
9. a method of getting oil or gas from the rock below the surface of the ground by making large cracks in it.