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  • The historical French heritage
    14 December 2010, by Frank

    France is very rich in systematic observations of coastal sea level over long time periods. The oldest (published) series of measurements were performed by the astronomers La Hire and Picard at Brest, France, in 1679, over about ten days. They repeated the experiment in 1692, over several months, again in Brest. Their aim was to study the tides and their results showed the fundamental importance of observation to understand and determine the characteristics of tides in a given place for the (…)

  • How to access the tide gauge observations
    20 February 2011, by Guy Woppelmann

    The files of average values
    Only the daily, monthly and annual averages calculated from quality controlled (QC’ed) data are provided in the data files. However, the graphs show the averages calculated from QC’ed observations (in blue) and non-QC’ed observations (in red). The averages are calculated from the Demerliac filter and the Doodson filter, with the possibility of a choice for the user. An example is given on the image below, which is taken from the web page of the La Rochelle (…)

  • Download
    8 January 2020, by Médéric Gravelle

    – Vertical velocities table
    The NGL14_Vertical-Velocities_Table provides the vertical GPS velocities and uncertainties from the 1069 stations fulfilling the criteria of 3 years of minimum length and data gaps not exceeding 30%, estimated by the NGL group using MIDAS (Blewitt et al. 2016). Daily time series
    The NGL14.zip file contains individual station data files of daily position time series in ITRF2014 with respect to the position at the mid time series epoch. These positions are (…)

  • About
    8 January 2020, by Médéric Gravelle

    The GNSS solution named ’NGL14’ is produced by the Nevada Geodetic Laboratory (NGL) using a Precise Point Positioning (PPP) data analysis strategy. The GipsyX software (version 1.0) from the Jet Propulsion Laboratory (JPL) is employed to produce daily position time series for over 17,000 globally distributed stations using JPL satellite orbits and clock products expressed in the IGS14 reference frame (Blewitt et al. 2018). The data set covers the period January 1996 to March 2022.
    This (…)

  • Le patrimoine historique
    28 mars 2008, par Guy Woppelmann

    La France est très riche en observations systématiques de hauteur d’eau le long des côtes sur de longues périodes de temps. Les plus anciennes séries de mesures (publiées) furent réalisées par les astronomes La Hire et Picard à Brest, en France, en 1679 pendant une dizaine de jours. Ils renouvelleront leur expérience en 1692, pendant plusieurs mois, toujours à Brest. Leur objectif : l’étude de la marée. Leurs résultats montreront l’intérêt fondamental de l’observation pour connaître et (…)

  • DOI ULR-repro3 solution
    27 May 2022, by Médéric Gravelle

    – General information Access the data by clicking on the Download tab
    Title: GPS Solution ULR7a DOI identifier: 10.26166/sonel_ulr7a Publisher: SONEL Data Assembly Centre Publication year: 2022 Version: a Temporal coverage: 2000-01-01 / 2020-12-31 Tile: The ULR-repro3 GPS data reanalysis solution (aka ULR7a) Language: English Authors
    Médéric Gravelle [1], Kevin Gobron [2], Guy Wöppelmann [1] Affiliation: [1]: UMR 7266 LIENSs, CNRS/LRU, La Rochelle, (…)

  • Statistics
    8 January 2020, by Médéric Gravelle

    Vertical velocity field Estimated (robust) velocities: 1069 CGPS@TG 872 Average of formal errors: 0.83 mm/yr Median of formal errors: 0.67 mm/yr

  • Download
    17 January 2020, by Médéric Gravelle

    – Vertical velocities table
    The JPL14_Vertical-Velocities_Table provides the vertical GPS velocities and uncertainties from the 436 stations fulfilling the criteria of 3 years of minimum length and data gaps not exceeding 30%, estimated by the JPL group.
    – Daily time series
    The JPL14.zip file contains individual station data files of daily position time series in ITRF2014 with respect to the position at the epoch 2023-01-01. These positions are expressed in meters in the local frame (…)

  • À-propos
    3 novembre 2020, par Guy Woppelmann

    La solution GPS ULR6b est une version actualisée de ULR6a, alignée dans le repère de référence terrestre ITRF2014, alors que ULR6a est dans l’ITRF2008. Les deux solutions ULR6 résultent de la réanalyse de 19 ans de données GPS allant de 1995 à 2014, réalisées dans le cadre de la seconde campagne de réanalyse de l’International GNSS Service (IGS, plus d’infos ici).
    Les observations de phase de l’onde porteuse GPS ont été analysées en double-différence, sans ionosphère, sur un réseau de 756 (…)

  • About
    17 January 2020, by Médéric Gravelle

    The GNSS solution named ’JPL14’ is produced by the Jet Propulsion Laboratory (JPL) group using a Precise Point Positioning (PPP) data analysis strategy. JPL’s GipsyX software is employed to produce daily position time series for over 2,000 globally distributed stations using JPL satellite orbits and clock products expressed in the IGS14 reference frame. The data set covers the period January 1994 to April 2022. This GNSS data analysis strategy complies with the standards (models, (…)