Multi-technique facilities as the key in modern geodesythe PASA case study
- J. Zurutuza
- M. J. Sevilla
- M. C. Ruiz
- J. Arnoso
- E. Vélez
- M. González
- P. Vaquero
- A. Aginaga
- M. Elorza
- F.G. Montesinos
ISSN: 0212-9280
Year of publication: 2022
Issue Title: XII Congreso Internacional de Geomática y Ciencias de la Tierra 2022.
Issue: 179
Pages: 121-128
Type: Article
More publications in: Topografía y cartografía: Revista del Ilustre Colegio Oficial de Ingenieros Técnicos en Topografía
Abstract
Multi-technique observations are the key to modern geodesy. In scenarios where sea level is monitored and linked to global/regional frames, this statement is even more relevant. Not only GNSS observations must be considered, but other techniques such as leveling and/or gravimetric measurements play a major role in the links to International frames that are necessary to unify geodetic measurements. We show the work being regularly done by the EUREF's ARA DAC&OC in the Pasaia harbor, where GNSS observations are combined together with leveling, both geometric and trigonometric, and gravity measurements: A) Daily/weekly GNSS measurements provide the vertical velocities, needed to be considered to properly remove local/regional crustal movements from sea level variations. B) Leveling is needed to detect deformations in the building and to link the heights to the National Spanish Leveling Network (REDNAP). Trigonometric leveling is used to transfer the tide gauge registered values to the GNSS antenna, located at the roof of the AZTI's facilities. C) Gravity will give us an additional source and access to the geopotential surface to which heights must be referred to. Regularly scheduled surveys provide both, the picture and the evolution of the links of the sea level measurements with respect to other independent techniques, very especially when the expected rates to be measured are within a few millimeters per year.