European Terrestrial Reference System 1989
The European Terrestrial Reference System 1989 ( ETRS89 ) is a three-dimensional geodetic reference system . It was defined by the European Sub-Commission of the IAG (EUREF) as firmly connected to the stable part of the Eurasian continental plate and identical to the ITRS for epoch 1989.0. The ETRS89 is implemented by EUREF through the sporadically published ETRF_YY (European Terrestrial Reference Frame [with designation of the year]) - three-dimensional coordinates and speeds of selected fixed points, which are measured with global measurement methods such as VLBI , Satellite Laser Ranging (SLR), Global Positioning System (GPS) and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS). These points form hierarchy level A of the ETRF. At the end of the 1980s and the beginning of the 1990s, mobile measurement campaigns were still taking place on land-marketed fixed points, today the ETRS89 is obtained on a European level through permanent GPS measurements on the station points of the EPN (EUREF Permanent GPS Network). Due to the long observation times and the stability of the points located on fixed structures, the mean accuracy of the coordinates is a few millimeters. The station speeds reflect the movement of the earth's crust within the Eurasian plate. The ETRS89 was recommended by the EU as a uniform reference system for European spatial data.
At the epoch January 1st 1989 the coordinates from ETRS89 and WGS84 were less than one meter apart, so that both systems can be regarded as identical within this positional accuracy.
The geophysical system ETRS89 (see geodetic datum ) has been assigned the geometric reference ellipsoid GRS80 as the best-adapting computing surface .
ETRS89 and the surveying administrations of the federal states of the Federal Republic of Germany
In Germany, the Working Group of the Surveying Administrations of the Federal States of the Federal Republic of Germany (AdV) decided in 1991 to introduce the ETRS89 as a uniform, official position reference system for all of Germany. As a result, a national compression level of hierarchy B of the EUREF network for Germany DREF and, as hierarchy level C, filling networks of the federal states C networks (e.g. SNREF for Saxony) were created. Today, the ETRS89 in Germany is implemented by SAPOS , the satellite positioning service of the German national surveying service, highly accurate, homogeneous and comprehensive for all areas of surveying.
In 1995 the AdV decided to introduce ETRS89 in conjunction with UTM mapping (see UTM coordinate system ). With this decision, there is an obligation for all land surveying administrations to also transfer the components of the real estate cadastre to the ETRS89 / UTM.
With the implementation of the ETRS89 / DREF91 (implementation 2016), the AdV decided on September 21, 2016 to introduce the integrated spatial reference 2016 .
- Bernhard Heckmann: Introduction of the ETRS89 / UTM position reference system when switching to ALKIS . In: Mitteilungen des DVW Hessen-Thüringen, 1/2005, p. 17ff.
- Ralf Strehmel: Official reference system for the situation - ETRS89. Surveying Brandenburg, 1/1996 ( PDF ).
- Bernhard Heck: Calculation methods and evaluation models for national surveying. Karlsruhe 1987.
- Spatial Reference Systems for Europe (PDF; 14.4 MB) Joint Research Center - European Commission (Engl.)
- Questions and answers on ETRS89 (cadastral modernization North Rhine-Westphalia)