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a blanket of air


the layer closest to the earth

air pressure

the weight of air pressing down to earth

local wind

a wind that results from a local difference in temperature

prevailing winds

global winds that always blow from the same direction

water cycle

water that continuously moves from earth's surface to the atmosphere and back to earth


during a part of the water cycle liquid water changes to gas


when water changes from a gas to a liquid


the amount of water vapor in the air


water that falls from the atmosphere to earth's surface

air mass

a large body of air that has the same temperature and humidity throughout


border where two air masses meet


the pattern of weather an area experiences over a long period of time

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