Description:
The Austrian Geoid 2008 is the official geoid model for Austria provided by the Austrian Federal Office for Metrology and Surveying (BEV). The two available versions describe the transformation between ellipsoidal heights w.r.t. the GRS80 (datum ETRS89, EPSG:4937) or w.r.t. the Bessel ellipsoid (datum MGI, EPSG:9267) and orthometric heights (EVRF2000 Austrian, EPSG:9274). The grid is consequently defined in ETRS89 (EPSG:4258) or in MGI (EPSG:4312), covering the area within 46.3° < latitude < 49.1° and 9.5° < longitude < 17.3°, with a spacing of 1.5' in latitude and 2.5' in longitude. in longitude. The model is based on 14001 gravity anomaly values, 672 deflections of the vertical and 170 GPS/levelling observations. The computation was performed in the framework of a remove-restore procedure, modelling the long wavelengths of the gravity field by the EIGEN-GL04S global model, and the short wavelengths by the Airy-Heiskanen model with a standard density of 2670 kg/m3. A digital terrain model with a resolution of 44 x 49 m was assembled as a combination of regional Austrian and Swiss models, as well as SRTM for the neighboring countries. The Least Squares Collocation (LSC) technique was used for the geoid computation, interpolating the empirical covariance of the residual quantities by the Tscherning-Rapp analytic covariance model. Special care was devoted to the optimal relative weighting of the input data, namely to the noise covariance models, especially concerning the GPS/levelling observations. The resulting hybrid geoid model was assessed by comparing it with independent GPS/levelling information, leading to an estimated accuracy of the order of 2-3 cm over the whole Austrian territory.
The model is also available at the BEV open data portal, and more information about it can be found on the BEV website.
Both versions of the geoid model are listed as transformation surfaces in the EPSG repository:
• EPSG:9276 – Austrian Geoid 2008 (GRS80)
• EPSG:9277 – Austrian Geoid 2008 (Bessel)
Model Citations:
R. Pail, N. Kühtreiber, B. Wiesenhofer, B. Hofmann-Wellenhof, G. Of, O. Steinbach, N. Höggerl, E. Imrek, D. Ruess, C. Ullrich (2008). The Austrian hybrid geoid in the ETRS89 system: Austrian Geoid 2008 (GRS80). V. 1.0. GFZ Data Services. DOI: 10.5880/isg.2008.001
R. Pail, N. Kühtreiber, B. Wiesenhofer, B. Hofmann-Wellenhof, G. Of, O. Steinbach, N. Höggerl, E. Imrek, D. Ruess, C. Ullrich (2008). The Austrian hybrid geoid in the MDI system: Austrian Geoid 2008 (Bessel). V. 1.0. GFZ Data Services. DOI: 10.5880/isg.2008.002
References:
R. Pail, N. Kühtreiber, B. Wiesenhofer, B. Hofmann-Wellenhof, C. Ullrich, N. Höggerl, D. Ruess, E. Imrek (2009).
The official Austrian geoid solution 2008: Data, Method and Results. Poster presentation at EGU General Assembly 2009, 19-24 April 2009, Vienna, Austria.
N. Höggerl, C. Ullrich, R. Pail (2009). The Austrian Geoid 2008. Poster presentation at EUREF Symposium 2009, 27-30 May 2009, Florence, Italy.
R. Pail, N. Kühtreiber, B. Wiesenhofer, B. Hofmann-Wellenhof, G. Of, O. Steinbach, N. Höggerl, E. Imrek, D. Ruess, C. Ullrich (2008). The Austrian Geoid 2007. VGI - Österreichische Zeitschrift für Vermessung & Geoinformation, 96(1/2008), pp. 3-14.
Web of Science ID:
DRCI:DATA2023050026130109
Digital object identifier:
DOI: 10.5880/isg.2008.001 (GRS80 geoid in ISG format)
DOI: 10.5880/isg.2008.002 (Bessel geoid in ISG format)
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