GIS Quiz 3

Geographic Coordinate System

A system that uses spherical coordinates (latitude and longitude) to locate points on the Earth's surface.

Planimetric/Projected Coordinate System

A 2D coordinate system that uses linear units (e.g., meters, feet) to locate points on a flat surface.

Graticule

A network of lines representing meridians and parallels on a map.

Datum

A reference point or surface used to define the location of points on the Earth's surface.

Standard Parallel

A line of latitude where the map projection is tangent to the Earth, resulting in no distortion.

Central Meridian

A line of longitude that serves as the center of a map projection.

False Easting/Northing

Linear values applied to the origin of a coordinate system to ensure all coordinates are positive.

Cartesian Coordinate System

A coordinate system that uses X and Y axes to define locations on a 2D plane.

UTM (Universal Transverse Mercator)

A projected coordinate system that divides the Earth into 60 zones, each 6 degrees of longitude wide.

U.S. State Plane

A coordinate system used in the United States for local mapping, divided into 120 zones.

Albers Equal Area Conic

A conic map projection that preserves area, commonly used for thematic mapping of North America.

Web Mercator

A cylindrical projection based on a sphere, commonly used for web mapping applications.

False Origin

A shifted origin in a coordinate system to avoid negative coordinates.

Secant Projection

A map projection where the surface intersects the Earth at two lines (standard parallels).

Conformal Projection

A map projection that preserves angles locally, but not necessarily area or distance.