Division 1.1 Definitions

In addition to the definitions set out in Article 2, the following definitions shall apply:

• ‘datum’ means a parameter or set of parameters that define the position of the origin, the scale, and the orientation of a coordinate system, in accordance with EN ISO 19111,

• ‘geodetic datum’ means a datum describing the relationship of a coordinate system to the Earth, in accordance with EN ISO 19111,

• ‘coordinate system’ means a set of mathematical rules for specifying how coordinates are to be assigned to points, in accordance with EN ISO 19111,

• ‘coordinate reference system’ means a coordinate system which is related to the real world by a datum, in accordance with EN ISO 19111. This definition includes coordinate systems based on geodetic or Cartesian coordinates and coordinate systems based on map projections.

• ‘map projection’ means a change of coordinates, based on a one-to-one relationship, from a geodetic coordinate system to a plane, based on the same datum, in accordance with EN ISO 19111,

• ‘compound coordinate reference system’ means a coordinate reference system using two other independent coordinate reference systems, one for the horizontal component and one for the vertical component, to describe a position, in accordance with EN ISO 19111,

• ‘geodetic coordinate system’ means a coordinate system in which position is specified by geodetic latitude, geodetic longitude and (in the three-dimensional case) ellipsoidal height, in accordance with EN ISO 19111F1,

• F2‘mean sea level’ (MSL) means the average height of the surface of the sea at a tide station for all stages of the tide over a 19-year period, usually determined from hourly height readings measured from a fixed predetermined reference level (chart datum),

• ‘lowest astronomical tide’ (LAT) means the lowest tide level which can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions.