| Question | Answer |
|---|---|
| water cycle | the process that water goes through when it is evaporated into the air and to the land as rain or snow |
| tornado | a dangerous windstorm produced by funnel-shaped clouds with winds of up to 300 miles per hour |
| thunderstorm | a storm with heavy rain, lightening, and thunder |
| rotation | the act of rotating as if on an axle |
| revolution | one complete movement made by one object around another |
| relative humidity | the amount of water vapor in the air divided by the total amount of water the air could hold |
| precipitation | the falling to earth of any form of water (rain or snow or hail or mist.) |
| open-ocean zone | the area of the ocean over the continental slope and abyssal plane |
| near-ocean zone | the ocean zone that starts at the low-tide mark and goes out into the ocean |
| mass extinction | when many types of living things become extinct at the same time |
| intertidal zone | the region that lies between the low and high tide lines |
| groundwater | water that fills the cracks and pores in underground soil and rock layers |
| hurricane | a strong tropical cyclone with speeds that are at least 74 miles per hour and a calm center; they usually produce a lot of rain |
| front | the boundary line between two air masses |
| evaporation | the change of a liquid into a vapor |
| currents | the movement of water in a river or an ocean |
| coral reefs | limestone structures that contain the shells of animals |
| continental slope | the very steep land that follows the continental shelf to lead to the flat abyssal plain |
| continental shelf | a shallow underwater plain that is actually the edge of a continent |
| climate | the weather in some location averaged some long period of time |
| blizzard | a heavy snowstorm with strong winds |
| axis | the earth's imaginary line that runs from the North Pole through the center of earth to the South Pole |
| atmosphere | the mixture of gasses that surrounds a planet |
| air pressure | the weight of air the atmosphere pressing down on earth |
| abyssal plain | the floor of the deep ocean which includes some of the flattest place on earth |
