Which system does the Geographic Coordinate System (GCS) use to determine locations?

The Geographic Coordinate System (GCS) employs latitude and longitude to pinpoint locations on the Earth's surface. Latitude measures the distance north or south of the Equator, expressed in degrees, while longitude measures the distance east or west of the Prime Meridian, also expressed in degrees. This spherical coordinate system allows for the identification of any point on Earth uniquely, which is essential for mapping, navigation, and geographic analysis.

Other systems listed may represent coordinates but do not specifically apply to how geographical locations are defined on the Earth's surface. For instance, northing and easting is typically part of a projected coordinate system, such as the Universal Transverse Mercator (UTM) system. Degrees and minutes refer to subdivisions of degree measurements and don't directly indicate a coordinate system, while Cartesian coordinates involve a grid system based on right angles and are usually applied in flat, two-dimensional spaces. Thus, latitude and longitude are the foundational elements used in the GCS for spatial referencing.