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Assessing the accuracy of predicted ocean tide loading displacement values / Nigel Penna in Journal of geodesy, vol 82 n° 12 (December 2008)  

Public [article]  inJournal of geodesy > vol 82 n° 12 (December 2008) . - pp 893 - 907 Titre : Assessing the accuracy of predicted ocean tide loading displacement values Type de document : Article/Communication Auteurs : Nigel Penna, Auteur ; M. Bos, Auteur ; Trevor Baker, Auteur ; H. Scherneck, Auteur Année de publication : 2008 Article en page(s) : pp 893 - 907 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique [Termes IGN] interpolation bilinéaire [Termes IGN] marée océanique [Termes IGN] positionnement par GPS [Termes IGN] surcharge océanique Résumé : (Auteur) The accuracy of ocean tide loading (OTL) displacement values has long been assumed to be dominated by errors in the ocean tide models used, with errors due to the convolution scheme used considered very small (2–5%). However, this paper shows that much larger convolution errors can arise at sites within approximately 150 km of the coastline, depending on the method used to refine the discrete regularly spaced grid cells of the ocean tide model to better fit the coastline closest to the site of interest. If the local water mass redistribution approach is implemented, as used in the OLFG/OLMPP software recommended in the IERS 2003 conventions, OTL height displacement errors of up to around 20% can arise, depending on the ocean tide model used. Bilinear interpolation only, as used in the SPOTL and CARGA softwares for example, is shown from extensive global and regional comparisons of OTL displacement values derived from the different methods and softwares to be more appropriate. This is verified using GPS observations. The coastal refinement approach used in the OLFG/OLMPP software was therefore changed in August 2007 to use bilinear interpolation only. It is shown that with this change, OTL displacement values computed using OLFG/OLMPP, SPOTL and CARGA invariably agree to the millimetre level for coastal sites, and better than 0.2 mm for sites more than about 150 km inland. Copyright Springer Numéro de notice : A2008-472 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0220-2 En ligne : https://doi.org/10.1007/s00190-008-0220-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29541 [article]

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
266-08111	RAB	Revue	Centre de documentation	En réserve L003	Disponible
266-08112	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Sea surface topography and the geoid, IAG symposium, Edinburgh, 1989 / Hans Sunkel (1990)  

Public Titre : Sea surface topography and the geoid, IAG symposium, Edinburgh, 1989 Type de document : Actes de congrès Auteurs : Hans Sunkel, Éditeur scientifique ; Trevor Baker, Éditeur scientifique Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 1990 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 104 Conférence : IAG 1989, 125th general meeting & IAG symposia 03/08/1989 12/08/1989 Edimbourg Royaume-Uni Importance : 187 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-0-387-97268-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique [Termes IGN] altimétrie [Termes IGN] géoïde [Termes IGN] Global Positioning System [Termes IGN] niveau moyen des mers [Termes IGN] surface de la mer Index. décimale : CG1989 Actes de congrès en 1989 Numéro de notice : 67632 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Actes DOI : 10.1007/978-1-4684-7098-7 En ligne : https://doi.org/10.1007/978-1-4684-7098-7 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=37128

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
67632-01	CG.89	Livre	Centre de documentation	En réserve M-103	Disponible

Methods of tidal loading computation / Trevor Baker in Bulletin international des marées terrestres, n° 94 (juin 1985)

Public [article]  inBulletin international des marées terrestres > n° 94 (juin 1985) . - pp 6365 - 6373 Titre : Methods of tidal loading computation Type de document : Article/Communication Auteurs : Trevor Baker, Auteur Année de publication : 1985 Article en page(s) : pp 6365 - 6373 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique [Termes IGN] marée océanique [Termes IGN] marégraphie [Termes IGN] masse de la Terre [Termes IGN] perturbation [Termes IGN] surcharge océanique Résumé : (Auteur) A general review is given of the various methods that have been used for tidal loading computations. An expansion of the ocean tide distribution into surface spherical harmonics and then a summation with an appropriate combination of load Love numbers is useful when only the lowest degree terms are involved, as for example in calculating the tidal perturbations of artificial satellites or the loading response due to the oceans at distances greater than about 1500 km. For load calculations at any distance from the coast, methods have been developed which involve calculating the response of the Earth to loads that are uniform over a limited area or cell. These cells can be either polygons, templates or discs. These should all give equivalent results provided that care is taken in choosing the size of the cells, particularly for the nearest sea area where the Earth's response, the marine tide (and the coastal geometry) are all varying rapidly with distance. If a cell has dimensions of order 2°C. , then the load response of the Earth at distances greater than 10°C from the cell becomes the same as the response due to an equivalent point mass load acting at the centre of the cell. Thus, if the cell size relative to the distance from the observation site is suitably chosen, then the computation reduces to the summation of the effects due to a set of point mass loads. The overall accuracy of a tidal loading computation is mainly determined by the uncertainties in the shelf and ocean tide models used (including that arising from the mass conservation problem) Numéro de notice : A1985-120 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33416 [article]