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Earth and Space Systems

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renewable resources
resources that nature can produce again and again in a relatively short period of time such as lumber
nonrenewable resources
resources that nature can not replace quickly enough to meet people's needs such as fossil fuels
inexhaustible resources
resources that are never used up as they are being used such as sunlight, wind, or waves
surface water
any water on the ground that meets the atmosphere
ground water
water found below the surface of land; a source of drinking water
aquifer
an underground permeable rock layer through which water flows freely
watershed
the total land area from which water drains into a stream, river, or lake
climate changes
long-term alteration in global weather patterns, including increases in temperature and storm activity
cycle
a period of time during which one complete sequence of a recurring series of events occurs
weathering
the process by which water, ice, wind, heat, animals, and plants act to break up rock
rock cycle
the continuous process in which new rock is formed from old rock
metamorphosis
a change in form
galaxy
a large grouping of stars and planets in space
light year
the distance that light travels in one year; used to measure vast distances (1 light year=just under one trillion kilometers)
lunar cycle
the continuous waxing and waning phases of the moon
competition
the struggle between organisms for limited resources such as food or light (ex: between weeds and flowers for the same nutrient supply)
characteristics
features or qualities that distinguish something
quality
an essential identifying nature or character of something
modify
to make small changes to something
outcome
a result, or the way that something turns out in the end