Unit 7

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Across
  1. 3. mining a mining technique that uses a large visible pit or hole in the ground
  2. 5. Energy that comes from the movement of water driven by the gravitational pull of the Moon.
  3. 6. energy from the sun that is converted into thermal or electrical energy
  4. 9. An area in which the air temperature is generally higher than the temperature of surrounding rural areas.
  5. 12. An increase in the percentage and in the number of people living in urban settlements.
  6. 13. involves the removal of the Earth's surface all the way down to the level of the mineral seam.
  7. 15. A fossil fuel that forms underground from partially decomposed plant material (organic sedimentary rock)
  8. 16. Natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases
  9. 17. The development of industries for the machine production of goods.
  10. 18. liquid fossil fuel; oil
  11. 19. A period of global cooling during which continental ice sheets and mountain glaciers expand.
  12. 20. electric or motive power generated by a nuclear reactor.
Down
  1. 1. A resource where falling water turns a turbine in a dam, which is connected to a generator that converts kinetic energy into electrical energy.
  2. 2. The removal of trees faster than forests can replace themselves.
  3. 4. A gas with high methane content, found along with petroleum and is used as a fuel.
  4. 7. Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.
  5. 8. Overall weather in an area over a long period of time
  6. 10. A natural resource that can be replaced at the same rate at which the resource is consumed
  7. 11. energy from steam or hot water produced from hot or molten underground rocks.
  8. 14. A natural resource that is not replaced in a useful time frame.