EUVN_DA: Establishment of a European continental GPS/leveling network

Abstract

EUREF, the Subcommission for the European Reference Frame within IAG Commission 1 in cooperation with the European Geoid and Gravity Project (EGGP) is developing a homogeneous continental GPS/leveling database. EUVN_DA, the Densification Action of the EUVN (European Unified Vertical Reference Network) project is designed to support the development of the new European geoid solutions and to contribute to the realization of an accurate continental height reference surface. The cm-accuracy GPS/leveling database could also be used for future realizations of the European Vertical Reference System (EVRS) and for the analysis of the national height networks. The establishment of the EUVN_DA network was started in 2003 and the first version of the database will be released in 2007. The database now consists of more than 1200 GPS/leveling points contributed from 20 countries. The GPS coordinates are referred to ETRS89 and the leveling data to EVRS2000. The EUVN_DA benchmarks are integrated into UELN (United European Leveling Network) to assure the long term homogeneity. Because of the large number of points, a continental coordinated GPS campaign could not be planned. The GPS database mostly relies on existing measurements, which should fulfill the quality requirements. This paper introduces the activities within the EUVN_DA project, gives an overview on the actual status and presents the first results on the analysis of the continental geoid solutions.