Human and Natural Impacts

4. The action or the process of clearing forests.
5. The quality or state of being urbanized by increasing the size and population of cities and towns.
6. When ash, gas, and/or lava are released from a volcano—sometimes explosively.
9. The spreading of something more widely.
10. The gases surrounding the Earth that protect life.
12. A natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.
13. The process that moves carbon through Earth’s hydrosphere, geosphere, atmosphere, and biosphere.
15. All the water on the earth's surface, such as lakes and seas, and including water over the earth's surface, such as clouds.
16. Gases that trap heat in the atmosphere (carbon dioxide CO2, methane CH4, nitrous oxide N2O, and fluorinated gases).

1. The short-term conditions of the atmosphere at a particular place and time, including temperature, precipitation, cloud cover, and wind.
2. A large natural or artificial lake used as a source of water supply.
3. The trapping of the sun's warmth in a planet's lower atmosphere.
7. The weather conditions prevailing in an area over multiple decades.
8. The increase in Earth's overall average temperature in recent decades.
11. Streams of circulation in ocean waters that are produced by gravity, wind friction, temperature differences, and water density variation.
14. A result that occurs when a rocky, metallic, or icy body hits the Earth's surface.