EUREF 2019 Symposium
The Estonian Land Board has a great pleasure to invite you to attend the EUREF 2019 Symposium, which will take place from Wednesday, May 22, 2019 to Friday, May 24, 2019 in Tallinn, Estonia. A half day tutorial will be held on 21st of May.
EUREF is the International Association of Geodesy (IAG) Reference Frame Sub-Commission for Europe. The Sub-Commission EUREF was founded in 1987 at the International Union of Geodesy and Geophysics (IUGG) General Assembly held in Vancouver.
The EUREF Symposium has been organized since 1990 and the scope of the symposium covers EUREF activities, such as the realisation, maintenance, and usage of ETRS89, EVRS and the EUREF Permanent Network.
Session 1 – Systems: ETRS89, EVRS
EUREF designed and established the European Geodetic Reference Systems. The European Terrestrial Reference System 89 (ETRS89) has a continent-wide significance. It is based on the International Terrestrial Reference System (ITRS), but tied to the stable part of Europe, so that the relationship between the two systems is entirely defined by a similarity transformation formula. ETRS89 unifies national reference systems for surveying, mapping, GIS and navigation in Europe. The benefit of ETRS89 is well demonstrated through its acceptance by several communities, e.g. EuroControl and the European Commission. The European Vertical Reference System (EVRS) is a kinematical height reference system. It is the basis for harmonisation of the vertical reference of spatial coordinates.
Presentations of the session report on legal acceptance, potential usage in geo-referencing applications and benefit for practice of the outlined geodetic reference systems and their practical realisations.
Session 2 – Networks: EPN, UELN, Densification
The reference networks through their observations are maintaining but also providing access to the reference system realisations. The EUREF Permanent Network (EPN) and the United European Levelling Network (UELN) are the core infrastructures of EUREF. The EPN is linked to the global network of the International GNSS Service (IGS) and contributes to the definition of the International Terrestrial Reference System (ITRS) realisations, but also serves as reference for the national permanent GNSS networks.
This hierarchy ensures the conformity and homogeneity of the geodetic reference system realisations from the global to national level.
The operation of a permanent GNSS network requires several well organized components: network coordination, data centres, analysis centres and product gateways. The routine cooperation with the station managers and the user community guarantees the appropriate implementation and usage of GNSS. The objective of the UELN is to establish a unified vertical datum for Europe at the one-decimetre level. Due to the different technology characteristics of GNSS and levelling, UELN is developing on a much longer time scale. However, the GNSS needs for interaction with the height reference systems and networks may leading to changes in the practical implementation. The session presents experiences and improvements of the provision and dissemination of data and results stemming from the geodetic reference networks. Improved analysis strategies and the latest results are expected to be presented.
Session 3 – Techniques: GNSS, Levelling, Combination
Geometry and gravity related measurement techniques allow for implementation of a European geodetic reference frame. Nowadays, applications of a Global Navigation Satellite Systems (GNSSs) are the dominant technique measure the geometry for continental regions. Direct measurements of the gravity or levelling are techniques related to the gravity field of the earth. All techniques need to take variation of system earth into account, if a longer time period or higher accuracy of site locations is in the focus.
Combination of different techniques is not only a validation of one technique against another one, but also opens new applications, e.g. levelling with GPS GNSS by using known geoids’ information. EUREF supports such practical aspects by the European Vertical Reference Network (EUVN) and EUVN-DA actions. GNSS and levelling measurements refer to discrete points. Developments of remote sensing methods extend the measurement of geodetic reference frame components from points to the surface, e.g. Synthetic Aperture Radar (SAR) measures height changes of the earth’s surface. The combination of SAR and GNSS is a challenge for the future. A couple of developments, which include to transport GNSS observations in real-time (data streaming) and even to calculate the receiver position in real-time are almost completed. The provision of geodetic reference frames in real-time has an important impact on current practise. The installation of new satellite navigation systems beside GPS and GLONASS, such as Galileo, BeiDou, and QZSS and NaviC, results in autonomous stand-alone solutions and combined multi-GNSS techniques. More satellites for the multi-GNSS scenario are going for deployment in the near future and investigations to understand improvements for geodetic aspects have already started.
This session presents developments, analysis and results of all techniques that are relevant for the establishment of reference frames. Real-time and multi-GNSS developments are of special interest.
Session 4 – Applications: Earth Sciences, Geo-Information
Geodetic techniques measure the situation on the earth’s surface. Modern space techniques extend observations to satellites orbiting the planet earth or even to extra-terrestrial targets. Today the position of particular sites on the earth’s surface and its variation is known to the sub-millimetre level for the period of decades. These techniques are also sensitive for many occurrences within the system earth, e.g. changes in the atmosphere, movement of tectonic plates and the state of solar radiation. The cross-linking of geodetic findings and knowledge from other geosciences is in the focus of research projects since long time. Geodesy contributes to understand the system earth. This session presents recent research projects of geosciences such as the European Plate Observing System (EPOS) and also updated results of ongoing projects. (Near) Real-time analysis of GNSS observations provides geophysical parameters in (near) real-time, e.g. information about the troposphere state. It contributes to online monitoring of the natural environment. Interdisciplinary cooperation for geo-monitoring and visualising in geo-information systems will also be addressed here.
Session 5 – National Reports
Representatives of European countries meet the challenge to report on national activities related to projects of geodetic reference systems. These are GNSS networks, height systems and geodetic methods based on the gravity field of the earth. New projects will be introduced, but also updated results of ongoing projects are of interest. Knowledge about progress in particular European countries provides valuable ideas for future planning in the home country and for a pan-European realisation of geodetic reference systems. The oral presentations should be concise, to allow plenty of nations to report.