Spatial referencing systems
Encyclopedia
A spatial reference system (SRS) or coordinate reference system (CRS) is a coordinate-based
local, regional or global system used to locate geographical entities. A spatial reference system defines a specific map projection
, as well as transformations between different spatial reference systems. Spatial reference systems are defined by the OGC
's Simple feature access using well-known text
, and support has been implemented by several standards-based geographic information system
s. Spatial reference systems can be referred to using a SRID
integer
, including EPSG codes defined by the International Association of Oil and Gas Producers.
Some of systems in existence are:
Coordinate system
In geometry, a coordinate system is a system which uses one or more numbers, or coordinates, to uniquely determine the position of a point or other geometric element. The order of the coordinates is significant and they are sometimes identified by their position in an ordered tuple and sometimes by...
local, regional or global system used to locate geographical entities. A spatial reference system defines a specific map projection
Map projection
A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane. Map projections are necessary for creating maps. All map projections distort the surface in some fashion...
, as well as transformations between different spatial reference systems. Spatial reference systems are defined by the OGC
Open Geospatial Consortium
The Open Geospatial Consortium , an international voluntary consensus standards organization, originated in 1994. In the OGC, more than 400 commercial, governmental, nonprofit and research organizations worldwide collaborate in a consensus process encouraging development and implementation of open...
's Simple feature access using well-known text
Well-known text
Well-known text is a text markup language for representing vector geometry objects on a map, spatial reference systems of spatial objects and transformations between spatial reference systems. A binary equivalent, known as well-known binary is used to transfer and store the same information on...
, and support has been implemented by several standards-based geographic information system
Geographic Information System
A geographic information system, geographical information science, or geospatial information studies is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data...
s. Spatial reference systems can be referred to using a SRID
SRID
A Spatial Reference System Identifier is a unique value used to unambiguously identify projected, unprojected, and local spatial coordinate system definitions...
integer
Integer
The integers are formed by the natural numbers together with the negatives of the non-zero natural numbers .They are known as Positive and Negative Integers respectively...
, including EPSG codes defined by the International Association of Oil and Gas Producers.
Some of systems in existence are:
- Universal Transverse Mercator coordinate systemUniversal Transverse Mercator coordinate systemThe Universal Transverse Mercator geographic coordinate system uses a 2-dimensional Cartesian coordinate system to give locations on the surface of the Earth. It is a horizontal position representation, i.e...
- British national grid reference systemBritish national grid reference systemThe Ordnance Survey National Grid reference system is a system of geographic grid references used in Great Britain, different from using latitude and longitude....
- Hellenic Geodetic Reference System 1987Hellenic Geodetic Reference System 1987The Hellenic Geodetic Reference System 1987 or HGRS87 is a geodetic system commonly used in Greece. The system specifies a local geodetic datum and a projection system...
- Irish grid reference system
- Irish Transverse MercatorIrish Transverse MercatorIrish Transverse Mercator , is the geographic coordinate system for Ireland. It was implemented jointly by the Ordnance Survey Ireland and the Ordnance Survey of Northern Ireland in 2001...
- Israeli Transverse MercatorIsraeli Transverse MercatorIsraeli Transverse Mercator is the new geographic coordinate system for Israel. The name is derived from the Transverse Mercator projection it uses and the fact that it is optimized for Israel. ITM has replaced the old coordinate system ICS. This coordinate system is sometimes also referred as...
- Israeli Cassini SoldnerIsraeli Cassini SoldnerIsraeli Cassini Soldner is the old geographic coordinate system for Israel. The name is derived from the Cassini Soldner projection it uses and the fact that it is optimized for Israel. This coordinate system is sometimes also referred as the "Old Israeli Grid"...
- Jordan Transverse MercatorJordan Transverse MercatorJordan Transverse Mercator is a grid system created by the Royal Jordan Geographic Center . This system is based on 6° belts with a Central Meridian of 37° East and a Scale Factor at Origin = 0.9998. The JTM is based on the International Hayford Ellipsoid 1924. No transformation parameters...
- Military grid reference systemMilitary grid reference systemThe Military Grid Reference System is the geocoordinate standard used by NATO militaries for locating points on the earth. The MGRS is derived from the UTM grid system and the UPS grid system, but uses a different labeling convention...
- United States National GridUnited States National GridThe United States National Grid is a point reference system of grid references commonly used in United States. It provides a nationally consistent language of location in a user friendly format. It is similar in design to the national grid reference systems used throughout other nations...
See also
- GeodesyGeodesyGeodesy , also named geodetics, a branch of earth sciences, is the scientific discipline that deals with the measurement and representation of the Earth, including its gravitational field, in a three-dimensional time-varying space. Geodesists also study geodynamical phenomena such as crustal...
- Geographic information systemGeographic Information SystemA geographic information system, geographical information science, or geospatial information studies is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data...
(GISGeographic Information SystemA geographic information system, geographical information science, or geospatial information studies is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data...
).