Conference PaperPDF Available

GNSS observation of semi-diurnal and quarter diurnal ocean tidal loading waves

June 2015

Conference: 26th IUGG General Assembly 2015

Authors:

Christine Heimlich

CNRS

University of Strasbourg

Frédéric Masson

University of Strasbourg

The ability of the Global Navigation Satellite System (GNSS) to produce precise positioning at the Earth's surface makes it a suitable tool to estimate crustal displacements due to Ocean Tidal Loading (OTL). We estimate horizontal and vertical displacements from 89 permanent stations located in Western Europe, for about a 2 year period (January 2009 to January 2011). The variation of position is estimated by double difference processing with GAMIT/GLOBK (Herring et al., 2010). We optimize our processing strategy, by choosing 2 hour session, shifted by 1 hour. We show that precise GNSS positioning allows to retrieve with a high accuracy the OTL signal not-only for the semi-diurnal tides, but also for the non-linear quarter-diurnal M4 wave.

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