| A | B |
|---|
| map | a model of an area of the earth's surface |
| map scale | the ratio of a distance represented on a map to the same distance on the earth's surface. two numbers separated by a colon indicate map scales. a large scale fraction indicates that the scale of the map is large, meaning that the area of the earth's surface that it represents is small |
| cartographer | a mapmaker |
| cardinal direction | one of the four key geographic directions: north, south, east, or west |
| Equator | the great circle of latitude perpendicular to the earth's rotational axis; the Equator is 0 degrees latitude and divides the earth into the Northern and Southern Hemispheres |
| latitude | also known as parallels; any line on a map or globe parallel to the Equator, including the Equator itself; they are all circles that are perpendicular to the axis of rotation of the earth. latitudes range from 0 degrees at the Equator to 90 degrees north (N) at the North Pole, and 90 degrees south (S) at the South Pole. |
| parallel | also known as a line of latitude because they appear parallel to the Equator when the globe is viewed from the side. The Equator is 0 degrees latitude. |
| longitude | also known as meridians. a line of longitude is any line on a map, perpendicular to parallels, that indicates the direction of true north. Scientists also define it as a semicircle on a globe that connects the North and South Poles. Longitude ranges from 0 degrees at the Prime Meridian to 180 degrees west (W), and 180 degrees east (E). |
| meridian | lines of longitude; the term meridian comes from the Latin word for "midday." a meridian marks the east-west position of the sun at its highest point in te sky. timewise, this sun position marks local noon |
| Prime Meridian | the semicircle on the globe that connects the North and South Poles and passes through Greenwich, England. This is 0 degrees longitude. |
| geographic coordinates | the latitude and longitude used to locate a point on the earth's surface |
| map projection | the transfer of geographic information from a 3D globe onto the 2D surface of a map. Map projections always distort geographic information |
| contour line | any line on a relief map that connects points of equal elevation above or below sea level |
| thematic map | a map that displays specific kinds of related data, often not geographic itself, on a standard map so that the viewer can recognize geographic relationships |
| geographic information system (GIS) | a system that uses digital map data, programs, hardware, and data storage systems to create and display information on maps. GIS also involves trained users who gather, plot, and analyze geographic information. GIS is particularly useful in that users can add or remove layers of data to show geographic relationships. |
