Practical aspects of the unification of height system realizations in Europe

Abstract

Three different approaches for the unification of height reference frames have been used to compute datum offsets between national vertical reference frames in Europe: the oceanographic approach, the spirit leveling approach and the gravity field approach. All three methods are discussed and advantages and drawbacks are evaluated. A set of tide gauge locations is used to compute height datum offsets between national height reference frames in Europe based on all three approaches. The results agree on a level of 5–10 cm. In summary, the gravity field approach is the most flexible approach. The ESA satellite gravity mission GOCE ensures a uniform global level in the range of 1–2 cm. Hence, the gravity field approach is a suitable approach for future realizations of the European Vertical Reference Frame as well as for the establishment of a World Height System.