Dictionary, Census of Population, 2021
Coordinate system

Definition

A coordinate system is a reference system based on mathematical rules for specifying positions (locations) on the surface of the earth. The coordinate values can be spherical (latitude and longitude), using angular units of measure such as degrees, minutes and seconds, or planar (Universal Transverse Mercator), using linear units such as metres.

Cartographic Boundary Files, digital boundary files, representative points and the Road Network File are disseminated in Lambert coordinates.

Reported in

2021 and 2016 (Lambert conformal conic)

2011, 2006, 2001, 1996, 1991, 1986 and 1981 (latitude and longitude)

1996, 1991, 1986, 1981, 1976 and 1971 (Universal Transverse Mercator)

Remarks

A coordinate system is usually defined by a datum, ellipsoid and projection and is specified in terms of units (e.g., degrees, metres).

The Lambert conformal conic projection provides good directional and shape relationships for mid-latitude regions with a mainly east‑to‑west extent. Standard parallels at 49° N and 77° N are most commonly used. The scale is correct along the standard parallels only; areal deformation decreases between and increases away from the standard parallels. The central meridian, normally at 91° 52' W, is a straight line about which the projection is symmetrical. False eastings and northings are given to ensure positive coordinate values in linear units of measure (metres).

The Lambert conformal conic map projection is the most common map projection used at Statistics Canada and generates Lambert coordinates in metres.

It is now common for geographic information system software to convert coordinates from one frame of reference to another, such as transforming the Lambert conformal conic projection to latitude and longitude coordinates.

The Universal Transverse Mercator (UTM) coordinate system is no longer used as the working coordinate system or for disseminating spatial digital data.

Refer to the related definitions of Cartographic Boundary Files (CBFs), Datum, Digital Boundary Files (DBFs), Map Projection, Representative Point, Road Network File (RNF) and Spatial Data Infrastructure (SDI).

Changes prior to the current census

For 2011, Cartographic Boundary Files, digital boundary files, representative points and the Road Network File were disseminated in latitude and longitude coordinates.

For 1996, the Street Network File was disseminated in latitude and longitude coordinates, but the working coordinate system was Universal Transverse Mercator (UTM).

Prior to 1996, the Street Network File was disseminated in UTM coordinates only.