[G02-P] Poster

[G02-P-20] Local vertical datum validation through the incorporation of GOCE variance and covariance information

Vassilios D. Andritsanos¹, Vassilios N. Grigoriadis², ^○Georgios S. Vergos², Thomas Gruber³, Thomas Fecher³ (1.Geospatial Technology Research Lab, Department of Civil Engineering and Surveying & Geoinformatics Engineering, Technological and Educational Institute of Athens, 12210 Athens, Greece, 2.GravLab, Department of Geodesy and Surveying, Aristotle University of Thessaloniki, University Box 440, GR 54-124 Thessaloniki, Greece, 3.Institute for Astronomical and Physical Geodesy, Technical University of Munich, Arcisstrasse 21, 80333 Munich, Germany)

After the completion of the GOCE mission, the information on height system validation and unification has been enriched, especially in the low to medium frequency of the gravity field spectrum. GOCE information is used for estimating height and/or geopotential offsets with respect to a conventional reference geopotential value, employing available GNSS/Leveling observations on trigonometric BMs and a GOCE-based geoid model. The scope of this work is to investigate the influence of GOCE errors in the determination of the Hellenic LVD. This is facilitated through a least-squares (LS) based adjustment of collocated GNSS/Leveling and GOCE geoid heights over a network of 1542 BMs in mainland Greece. The latest TIM-R5 and GOCO05s GOCE and GOCE/GRACE global geopotential models are used to represent the contribution of GOCE and GRACE to the Earth's gravity field. Four different weighting scenarios are used including standard a-priori error for the BMs heights, the GNSS heights and the geoid undulations, cumulative errors for the geoid heights and variance/covariance information from GOCE geoid models. The local geopotential offset Wo(LVD) is also calculated utilizing the weighting scenarios. Finally, variance component estimation is performed to evaluate the height (h, H, N) variance/covariance matrices using the GPS/leveling errors from the above weighting schemes.