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a way of representing the properties of an object or system


the layer of gases that surrounds Earth above the surface of liquid water and rocky material


the interface or boundaries of the layers of earth's atmosphere


the layer of liquid water that lies between the atmosphere and much of the upper layer of earths interior


the layer of rock that forms the solid outer shell at the top of earth interior


the upper portion of the lithosphere

earths interior

the region extending from the rocky part of Earth's surface to Earth's center

coordinate system

the system for determining the coordinates of a point


the angular distance north or south of the equator


the parallel on Earth midway between the geographic north and south poles with a latitude of zero


the angular distance east or west of the prime meridian


any semi circle on earth surface conecting the north and south geographic poles

prime meridian

the meridian of zero longitude


any region of space or the environment that has some measurable value of a given quantity at every point


the varying values of a field represented on maps to connect points of equal field values

contour lines

isolines that connect points of equal elevation


the rate of change from place to place within the fields (slope)

gradient formula

change in amount of field value/ change in horizontal distance

topographic map (contour map)

a comonly used model of the elevation fields of the surface of earth


the vertical distance of height above or below sea level


the side view of an areas landscape

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