Global Systems

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Across
  1. 4. A treaty to reduce greenhouse gases in 1997
  2. 5. the warming of Earth's atmosphere caused by increased concentrations of greenhouse gases from human activities, which trap more heat than the natural greenhouse effect
  3. 7. a large geographical region characterized by its climate
  4. 8. site for the disposal of waste materials
  5. 12. the complete disappearance of species
  6. 15. measure of the Earth's global average surface temperature increase that results from a doubling of atmospheric carbon dioxide
  7. 16. outermost rocky shell of a terrestrial planet or natural satellite
  8. 17. it is composed of roughly 78% nitrogen, 21% oxygen and 1% other
  9. 19. gases in Earth's atmosphere that trap heat
  10. 20. the dehydration of fertile land
Down
  1. 1. the gradual increase in the temp of the earth
  2. 2. acts as a protective shield by absorbing most of the sun's harmful ultraviolet radiation
  3. 3. the removal of forests
  4. 6. the sum of all ecosystems on earth
  5. 9. the sum of all water on and under earth surface
  6. 10. was a peace agreement
  7. 11. the total collection of all genes
  8. 13. long, cylindrical samples of ice drilled
  9. 14. the variety of all life on earth
  10. 18. a natural process that warms the earth