Detailed gravimetric quasigeoid QGZÚ-2013

Detailed gravimetric quasigeoid QGZÚ-2013 represents a transformation surface enabling transformation between altitudes H in the Baltic Vertical Datum – After Adjustment (Bpv) and ellipsoidal heights h in the European Terrestrial Reference System 1989 (ETRS89) /realization ETRF2000/ above the rotating ellipsoid Geodetic Reference System 1980 (GRS80). Data content creates height anomaly zeta expressed in the nodal points of regular grid (3'' x 3'') of geographical coordinates ETRS89. Height anomalies implements own transformation relationship that has the form h = H + zeta. Total mean square error of height anomaly is on the territory of the Czech Republic 1 cm, in the mountainous terrain and in border areas (up to 10 km from the border) can reach higher values, but not more than 3 cm. Quasigeoid model was computed using combined regional solution of linear gravimetric boundary value task for the correcting gravitational potential of the Earth, with the significant contribution of complete revised dataset of detailed points of gravimetric mapping of the Czech Republic performed in the frame of geophysical mapping between 1950 – 2010, and with the other data. Model can be applied especially in a special geodetic applications, in which a detailed knowledge of the course of the height anomaly is required in the given locality. In these applications, the model enables the calculation of local transformation parameters needed for the mutual transformation of heights in the Bpv and ETRS89 reference systems in a given locality. Please note that due to the different processing procedure, the results of the coordinate transformation between the Bpv and ETRS89 reference systems using this model may in the given locality differ from the results of the transformation performed using official transformation service or application Coordinate Transformation of the Geoportal ČÚZK. To guarantee a uniform process of transformations and to achieve homogeneous results, it is necessary to use the stated applications or processing software approved by ČÚZK.