Mercator map projection

UTM Coordinate System, based on the Universal Transverse Mercator map projection, is a planar locational reference system which provides positional descriptions accurate to 1 meter in 2,500 across the entire earth's surface except the poles.

The national grid is a standard Transverse Mercator map projection, using the Airey Spheroid and a false origin to the south west of the Isles of Scilly.

It is also based on the Transverse Mercator map projection. This system is more complicated than Geographic Coordinates as location is determined relative to 60 - six degree longitude wide zones that run north-south.

Based on the Universal Transverse Mercator map projection. At the poles, the Universal Polar Stereographic projection is used.

See also: GPS, Transform, Digital, Capture, Ground control