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Abiotic Factor

A nonliving part of an organism's habitat.


The grinding away of rock by other rock particles carried in water, ice, or wind.

Acid Rain

Rain that contains more acid than normal


Describes a substance that reacts strongly with metals and changes blue litmus paper red


A behavior or physical characteristic that helps an organism to survive in its habitat


An earthquake that occurs after a larger earthquake in the same area

Air Mass

A huge body of air that has similar temperature, humidity, and air pressure throughout

Air Pressure

the result of the weight of a column of air pushing down on an area

Alluvial Fan

a wide, sloping deposit of sediment formed where a stream leaves a mountain range


Elevation above sea level


An instrument used to measure wind speed

Aneroid Barometer

an instrument that measures changes in air pressure without using a liquid


A high-pressure center of dry air


The farming of water Organisms


The soft layer of the mantle on which the lithosphere floats


Earth's envelope of gases

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