The European Terrestrial Reference System 1989 (ETRS89) is an
ECEF
The Earth-centered, Earth-fixed coordinate system (acronym ECEF), also known as the geocentric coordinate system, is a cartesian spatial reference system that represents locations in the vicinity of the Earth (including its surface, interior ...
(Earth-Centered, Earth-Fixed)
geodetic
Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...
Cartesian reference frame, in which the
Eurasian Plate
The Eurasian Plate is a tectonic plate that includes most of the continent of Eurasia (a landmass consisting of the traditional continents of Europe and Asia), with the notable exceptions of the Indian subcontinent, the Arabian subcontinent and ...
as a whole is static. The
coordinate
In geometry, a coordinate system is a system that uses one or more numbers, or coordinates, to uniquely determine the position of the points or other geometric elements on a manifold such as Euclidean space. The order of the coordinates is sig ...
s and
map
A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes.
Many maps are static, fixed to paper or some other durable medium, while others are dynamic or interactive. Althou ...
s in Europe based on ETRS89 are not subject to change due to the
continental drift
Continental drift is the hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed. The idea of continental drift has been subsumed into the science of pl ...
.
The development of ETRS89 is related to the global
ITRS geodetic datum
A geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame) is a global datum reference or reference frame for precisely representing the position of locations on Earth or other pl ...
, in which the representation of the continental drift is balanced in such a way that the total apparent
angular momentum
In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity—the total angular momentum of a closed syste ...
of
continental plate
Continental may refer to:
Places
* Continent, the major landmasses of Earth
* Continental, Arizona, a small community in Pima County, Arizona, US
* Continental, Ohio, a small town in Putnam County, US
Arts and entertainment
* ''Continental'' ( ...
s is about 0. ETRS89 was officially born at the 1990
Florence
Florence ( ; it, Firenze ) is a city in Central Italy and the capital city of the Tuscany region. It is the most populated city in Tuscany, with 383,083 inhabitants in 2016, and over 1,520,000 in its metropolitan area.Bilancio demografico ...
meeting of EUREF, following its Resolution 1, which recommends that the terrestrial reference system to be adopted by EUREF will be coincident with ITRS at the epoch 1989.0 and fixed to the stable part of the Eurasian Plate. According to the resolution, this system was named European Terrestrial Reference System 89 (ETRS89). Since then ETRS89 and ITRS diverge due to the continental drift at a speed about 2.5 cm per year. By the year 2000 the two coordinate systems differed by about 25 cm.
The 89 in its name does not refer to the year of solution (realization), but rather the year of initial definition, when ETRS89 was fully equivalent to ITRS. The solutions of ETRS89 correspond to the ITRS solutions. For each ITRS solution, a matching ETRS89 solution is being made. ETRF2000, for example, is an ETRS89 solution, which corresponds t
ITRF2000 ETRS89 is realized by EUREF through the maintenance of the
EUREF Permanent Network (EPN) and continuous processing of the EPN data in a few processing centres. Users have access to ETRS89 via EPN data products and real-time streams of differential corrections from a set of public providers based on the EPN stations.
The transformation from ETRS89 to ITRS is time-dependent and was formulated by C. Boucher and Z. Altamimi
ETRS89 is the
EU-recommended frame of reference for
geodata for Europe.
It is the only geodetic datum to be used for
mapping and
surveying
Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial two-dimensional or three-dimensional positions of points and the distances and angles between them. A land surveying professional is ...
purposes in Europe.
It plays the same role for Europe as
NAD-83 for North America. (NAD-83 is a datum in which the
North American Plate
The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacific ...
as a whole is static, and which is used for mapping and surveying in the US, Canada, and Mexico.) ETRS89 and NAD-83 are based on the
GRS80 ellipsoid.
WGS84
The World Geodetic System (WGS) is a standard used in cartography, geodesy, and satellite navigation including GPS. The current version, WGS 84, defines an Earth-centered, Earth-fixed coordinate system and a geodetic datum, and also descri ...
originally used the GRS80 reference ellipsoid, but has undergone some minor refinements in later editions since its initial publication.
See also
*
WGS 84
The World Geodetic System (WGS) is a standard used in cartography, geodesy, and satellite navigation including GPS. The current version, WGS 84, defines an Earth-centered, Earth-fixed coordinate system and a geodetic datum, and also descri ...
*
ED50
*
AFREF
References
{{Reflist
External links
ETRS89 site (Spanish) ETRS89 site (French) ETRS89 site (English)Information from the Ordnance Survey of Ireland
Geodetic datums