ALBERT

Description: ETRS89 has become the common standard for harmonized horizontal coordinates in the European countries. In contrast, the national height networks are still determined by leveling with respect to different tide gauges and standards (height types, tide systems). The differences in the definitions cause height discrepancies up to a few decimeters along the borders. National geoid models are defined accordingly. Nowadays, GNSS-based height determination is widely used, which also increases the demand for geoid models as a height reference across borders. For large parts of the continent, the United European Leveling Network provides harmonized heights based on the standards of the EVRS. However, EUREF has yet to adopt a corresponding height reference surface officially. Thus, the EUREF Working Group “Unified European Height Reference” was formed by resolution in 2021 with the objective to enhance the usability of European heights for practical applications such as civil engineering, digital elevation models, etc. The main goal is to establish a European Height Reference Surface (EHRS) which is tailored to a consistent dataset of GNSS-leveling control points (EHRS_CP) referring to the latest ETRS89 and EVRS realizations. Furthermore, comprehensive information about the national integrated spatial reference systems, including heights and geoid models, shall be made available through the Information and Service System for European Coordinate Reference Systems (CRS-EU). The paper gives an overview of the rationale and current activities of the working group. Preliminary comparisons with selected gravimetric quasigeoid models provide an outlook on the increased accuracy of the new GNSS-leveling dataset.

Description: What do the transport sector, planning for the offshore industry, sea level rise monitoring, and environmental and coastal protection have in common? For all these fields, sustainability is nowadays a key aspect, and they all rely on accurate positioning and navigation across borders and between land and sea. Today, this is primarily done employing satellite techniques, but users are largely unaware that this requires a harmonized geodetic infrastructure, i.e., data and services, to determine accurate coordinates and heights relative to a common reference system. Until now, heights on land and charted depths in the Baltic Sea region were heterogeneous and not directly comparable. For example, paper charts of different harbors had different zero levels between countries or even within the same country. Working with this kind of information required expert knowledge. The Baltic Sea Hydrographic Commission has therefore laid the foundation for a unified chart datum in the Baltic Sea, the BSCD2000. A substantial part of the work could be realized with co-funding from the EU in the project “Finalizing Surveys for the Baltic Motorways of the Sea (FAMOS)”. In this paper, the concept of BSCD2000 and its implications for the users are briefly outlined, and applications given the UN sustainability goals are demonstrated. Based on BSCD2000, seamless and user-friendly navigation using satellites will become available for the first time in the Baltic Sea. BCSD2000 hence provides the foundation for novel applications like adaptive ship routing, which will promote the safety and efficiency of ship transport.