Last November (13th to 15th, 2017), Aline Déprez, from EPOS GNSS Data and Products and Ingénieure CNRS (ISTerre - Institut des Sciences de la Terre, Université Grenoble Alpes), attended the Colloque G2 2017 Géodésie – Rhéologie, an event hosted at Nice University.
GNSS Data & Products TCS provides data access and product access. The two portals each give access to data (products) through a distributed set of data (products) centres. EUREF Permanent GNSS Network (EPN) data and products are integrated as data nodes.
EPN is maintained by EUREF, one European level organization, and relies on 260+ GNSS stations, based on a partnership with site operators from about 30 countries.
The EPN is running in a well-organized environment and distributing GNSS data and products. EUREF is also providing products for 2000+ EPN densification stations. In addition, there are also several GNSS networks dedicated to solid earth studies at national level.
Virtual access to data/products/services
Relying on EUREF GNSS (Global Navigation Satellite System), geodetic observations (stored at RINEX) and derived products (site coordinate time-series and velocities, strain rate maps) and metadata (Level 0, 1, 2) will be accessible.
Virtual access to computational platforms
Using a software tools to facilitate the cross-disciplinary use of geodetic data and the interoperability with adjacent disciplines.
Access to validated data from EPOS stations through EPOS GNSS Data gateway:
► RINEX data
► Station metadata
Monitoring of the GNSS data quality.
Centralised facility to submit/validate EPOS station site logs.
Access to validated EPOS products through EPOS GNSS Product gateway:
► Positions and time series
► Strain rate fields
Generation of dedicated products:
► GNSS data analysis generating daily solutions, position time series and velocities (using Precise Point Positioning approach and Double Difference approach).
► Dense European Velocity including EPOS stations as well as EUREF densifation network.
► Strain rate fields.
► Distribution and maintenance of software package GLASS to provide access to GNSS data.
► GLASS (Geodetic Linking Advanced Software System) is an integrated software package deployed in a GNSS infrastructure to manage data and metadata
► Developed from the original Geodetic Seamless Archive Centers (GSAC) concept, GLASS is an open source platform under Creative Commons licensing.
For guaranteeing data availability, GLASS counts on a default repository (primary) decided by the data provider, a repository acting as a mirror of another (mirror) and an alternative repository (secondary). All data sources are provided by GNSS data repositories from multiple agencies – regional, national, EUREF and others.
The infographic shows the flow within EPOS from submission of RINEX data (and control of metadata by the M3G Center) to the dedicated EPOS GNSS analysis centers that compute positions, velocities and strain. The long term monitoring of data in EPOS is carried out by the Quality Monitoring Center (not part of GLASS package). GNSS Data and Product gateways are the main point of access to the users – also the EPOS Integrated Core Services (ICS) will use these to get metadata from the GNSS Thematic Core Service.
Data/Products portal architecture with web interface.
► EPOS GNSS Data gateway also offers access to data from EUREF stations belonging to EPOS through interface with regional and historical EUREF data repositories.
► EPOS GNSS Product gateway also offers access to EUREF products: European reference frame, weekly station positions, and densified EUREF solution.