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GSAC Software Makes the Grand Tour In Europe

  • Project Manager:
    Fran Boler
  • Software Engineers: Stuart Wier, Jeff McWhirter (2010-2012)
  • Date: 2013 - 2014
  • Locations: Italy, Greece, Portugal, France, Belgium, Iceland
  • Funding Source: NASA ROSES ACCESS, NSF

Written by Fran Boler
20 March 2014


UNAVCO’s Geodesy Seamless Archive Centers (GSAC) software system enables efficient searches for geodesy data at any number of independent data centers. There are tens of thousands of GNSS sites gathering data around the globe and hundreds of data centers to manage that data. When each data center makes an independent web site to share their data, the customer has to learn each data center’s search and distribution mechanisms. GSAC provides a consistent user access capability at each GSAC-enabled data center.

NASA originally funded UNAVCO, SOPAC, and CDDIS to develop the GSAC software, and NSF has funded UNAVCO to make the installation very easy. The software, which can be installed with typically one to two days effort, allows groups that gather data to simplify the data access across a large user base. European GNSS data centers that are part of a network of geoscience data centers called EPOS are making GSAC the centerpiece of their GNSS data access technology.

Participating data centers include:

  • Space & Earth Geodetic Analysis Laboratory (SEGAL), Universidade da Beira Interior, Departamento de Informática, Covilhã, Portugal. (SEGAL network)
  • Istituto Nazionale di Geofisica e Vulcanologia (INGV), Grottaminarda, Italy. (RING network)
  • National Observatory of Athens (NOA), Greece. (NOANet network)
  • Iceland Meteorology Office (IMO), Rejkyavik, Iceland. (IsCGPS network)
  • Geoazur, Université de Nice - Sophia-Antipolis, France. (RENAG and RGP networks)
  • The European Permanent Network Central Bureau, Royal Observatory of Belgium, GNSS Research Group. (EPN network)
  • National Technical University of Athens (NTUA), Dionysos Satellite Observatory, Higher Geodesy Laboratory.
  • Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), near Triest Italy. (FReDNet network)


To install and operate the thousands of GNSS stations and other geodesy instrumentation globally is a huge investment (on the order of 100 million dollars) undertaken by government research and civil infrastructure agencies. In the case of GNSS, the stations are dependent on the foundational satellites that represent a multi-billion dollar investment. The data generated by this infrastructure are broadly useful for positioning, solid Earth science, meteorology, water cycle, … the list goes on. To make this data easily available is an obvious goal that enables the investment to reap its maximum benefit. UNAVCO’s efforts to develop the GSAC software are part of a broad movement toward open data and data accessibility fostered by the White House, NASA, the National Science Foundation, the European Commission, and policy makers just about everywhere.


A significant challenge for any piece of software is meeting competing needs and emerging visions of what the software should do now and in the future. The institutions that have already adopted GSAC in Europe and several others that are likely to do so are meeting in Covilha, Portugal in April 2014 to discuss how to develop/improve GSAC in order to satisfy the community needs.

Related Links

Map Center:
University of Beira, Interior, Covilha, Portugal is the site of the 2014 GSAC Workshop


Last modified: 2020-01-28  22:54:30  America/Denver