| A | B |
| core | center of the Earth made up of hot iron mixed with other metal and rocks |
| mantle | surrounds the core a layer of hot, dense rock 1770 miles thick |
| magma | melted rock |
| crust | Earth's upper layer, a thin rocky shell that form she surface |
| continent | large areas of the crust, there are 7 |
| plate tectonics | theory that explains how the continents were formed and why they move |
| earthquake | sudden and violent movement of the Earth's crust |
| fault | cracks in the Earth's crust |
| weathering | when water and ice, chemicls, and even plats break rocks apart into smaller pieces |
| erosion | when water, wind, and ice move away weathered rocks |
| release | to relieve pressure |
| constant | happening a lot or all the time |
| accumulate | to increase in amount |
| continental shelf | a plateau off each coast of a continent that stretches for several miles underwater |
| trench | deep cuts in the ocean floor |
| groundwater | freshwater that filters through the soil into the ground |
| aquifer | underground layers of rock through which water flows |
| water cycle | process where water goes from the oceans, to the air, to the ground, and back to the oceans |
| evaporation | changes water from liquid to gas called water vapor |
| condensation | water changes from gas back to a liquid |
| precipitation | rain, snow, sleet, or hail |
| collection | water collects on the ground and in rivers, lakes, and oceans |
| occur | to be found in |
| define | to describe or establish |
| availability | state of being easy or possible to get or use |
| weather | changes in temperature, wind direction and speed, and air moisture that take place over a short period of time |
| climate | predictable patterns of weather in an area over many years |
| prevailing wind | major wind systems that follow patterns that are similar over time |
| current | steadily flowing streams of water in the world's seas |
| El Nino | weakened winds allow warmer waters to reach South America's coast, Spanish for "the boy" |
| La Nina | causes unusually cool waters and low rainfall in the eastern Pacific, Spanish for "little girl" |
| local wind | landforms cause wind patterns that are typical only in a small area |
| rain shadow | mountains block rain from reaching interior regions |
| climate zone | areas that have similar patterns of temperature and precipitation |
| biome | climate zones |
| urban climate | paved streets and stone buildings soak up and release more of the sun's heat energy |
| distribute | to spread out |
| alter | to change |
| smog | thick haze of smoke and chemicals |
| acid rain | chemicals in air pollution combined with precipitation |
| greenhouse effect | gases in the atmosphere trap the sun's warmth |
| crop rotation | changing what is planted from year to year |
| deforestation | cutting down forests without replanting |
| conservation | the careful use of a resource |
| irrigation | a process in which water is collected and distributed to crops |
| pesticide | powerful chemicals used to kill crop destroying insects |
| ecosystem | a place shared by plants and animals that depend on one another for survival |
| biodiversity | the variety of plants and animals living on the planet |
| layer | a thickness or fold |
| technique | a method of accomplishing something |