The IAG Reference Frame Sub-Commission for Europe, EUREF, symposium was held in Amsterdam 30 May – 1 June, 2018. There were a total of 120 participants and a traditional program with five sessions, including the National reports. The science sessions included the reference frames, European geodetic networks, observational techniques, and applications. During recent years, topical tutorial lectures have been organized prior the Symposium. This year the topic of the full-day Tutorial was InSAR-geodesy and geodetic infrastructure. InSAR is an emerging technique in geodesy, and the interest on it and possible applications seems to be great. This was reflected also in the presentations in the Symposium.

Another actual topic in the Symposium was an issue with new GNSS satellite systems, foremost Galileo. Up to now, lack of proper software has retarded applications, but this seems to be mostly solved. However, there is another issue, affecting especially permanent reference stations and precise positioning, both using calibrated antennas. Antenna calibrations have been done mainly for two GPS frequencies and Glonass. 

Group photo of the EUREF symposium 2018 (photo: Lennard Huisman)

What has been missing is the possibility to make the calibration also for Galileo and BeiDou, and this concern both the robot calibration and calibration in an anechoic chamber. This was recognized in a resolution of the Symposium, where EUREF …asks the EUREF community, GSA, ESA and the GNSS industry to support the IGS antenna working group in order to overcome the missing receiver antenna calibrations for Galileo signals. This information has been forwarded also to those places who are doing the calibrations or owns equipment for it.

There was also a resolution related to InSAR. As adopted in the Plenary, the resolution states that EUREF …recognising the potential of collocating InSAR transponders or reflectors with continuous GNSS stations and geodetic benchmarks, encourages the EUREF community to start to consider the integration of InSAR technology into reference system activities.

Being in the home place of NAP, the Normaal Amsterdams Peil, height questions were also on the agenda of the Symposium. A height and gravity related resolution was adopted, where the IAG Reference Frame Sub-commission for Europe (EUREF), recognising that physical (gravity related) heights have many important uses, for example in European and national height systems and in studies of sea level rise and for flood protection, and noting that precise regional gravity data and geoid models are necessary for height determination using satellite-based techniques, encourages National Mapping Authorities, universities and research institutes to release their gravity and height data where this is legally possible, and requests the EUREF Governing Board form a working group to study the optimal application of height and gravity data. The purpose is encourage institutes to release gravity and height data which have been more difficult to obtain for research and practical purposes, contrary to the open databases of GNSS data. Unfortunately legislation or adopted practicalities restrict release of gravity and height data in many countries.

The three-day Symposium was very active, and well organized in an inspiring environment of Amsterdam Nemo Science Museum. The social event included a memorable canal cruise to the conference dinner. Many thanks to the local organisers for the excellent event and great atmosphere. We welcome everyone to the 2019 EUREF Symposium in Tallinn.

Markku Poutanen
Chair of EUREF