TS 53 – Reference Frame Vertical

levelling using the motorised levelling technique. The system is defined to agree with the European Vertical Reference System (EVRS), implying for instance that normal heights are utilised. Due to the postglacial rebound, it is important that the observations are reduced to a common reference epoch. For this purpose, the new land uplift model NKG2005LU was constructed as a combination of the mathematical (empirical) model of Vestøl (2005) and the geophysical model of Lambeck, Smither and Ekman (1998). The reference epoch was chosen to 2000.0. The computation was made in collaboration with the other Nordic countries under the umbrella of the Nordic Geodetic Commission (NKG) and in co-operation with the IAG Reference Frame Sub Commission for Europe (EUREF). Data from the Netherlands