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Isostatic stability of the East Antarctic station Dumont d'Urville from long-term geodetic observations and geophysical models / Martine Amalvict in Polar research, vol 28 n° 2 (August 2009)
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Titre : Isostatic stability of the East Antarctic station Dumont d'Urville from long-term geodetic observations and geophysical models Type de document : Article/Communication Auteurs : Martine Amalvict, Auteur ; Pascal Willis , Auteur ; Guy Wöppelmann
, Auteur ; Eric Ivins, Auteur ; Marie-Noëlle Bouin
, Auteur ; Laurent Testut, Auteur ; Jacques Hinderer, Auteur
Année de publication : 2009 Article en page(s) : pp 193 - 202 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Antarctique
[Termes IGN] coordonnées GPS
[Termes IGN] déformation verticale de la croute terrestre
[Termes IGN] données géophysiques
[Termes IGN] rebond post-glaciaireRésumé : (auteur) Geodetic measurements of the vertical crustal displacement collocated with absolute gravity changes provide a discriminatory measurement of present-day glacial changes, versus more deeply seated rock motions caused by glacial isostatic adjustment (GIA). At the East Antarctic station of Dumont d'Urville, we compare the displacements derived from continuous DORIS (1993.0–2006.0) and Global Positioning System (GPS) (1999.0–2005.7) data, and observed changes in absolute gravity (2000–2006), with the predicted vertical displacement and change in gravity from GIA modelling. The geodetic results have mutual self-consistency, suggest station stability and provide upper bounds on both GIA and secular ice mass changes. The GIA models tend to predict amplitudes of rock motion larger than those observed, and we conclude that this part of Antarctica is probably experiencing a slight gain in ice mass, in contrast to West Antarctica. Numéro de notice : A2009-579 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article DOI : 10.1111/j.1751-8369.2008.00091.x En ligne : http://doi.org/10.1111/j.1751-8369.2008.00091.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88648
in Polar research > vol 28 n° 2 (August 2009) . - pp 193 - 202[article]Triangulated spherical splines for geopotential reconstruction / M.J. Lai in Journal of geodesy, vol 83 n° 8 (August 2009)
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Titre : Triangulated spherical splines for geopotential reconstruction Type de document : Article/Communication Auteurs : M.J. Lai, Auteur ; C.K. Shum, Auteur ; V. Baramidze, Auteur ; P. Wenston, Auteur Année de publication : 2009 Article en page(s) : pp 695 - 708 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur local
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] Earth Gravity Model 1996
[Termes IGN] équation de Laplace
[Termes IGN] fonction spline
[Termes IGN] fonction spline d'interpolation
[Termes IGN] modèle de géopotentiel
[Termes IGN] potentiel de pesanteur terrestreRésumé : (Auteur) We present an alternate mathematical technique than contemporary spherical harmonics to approximate the geopotential based on triangulated spherical spline functions, which are smooth piecewise spherical harmonic polynomials over spherical triangulations. The new method is capable of multi-spatial resolution modeling and could thus enhance spatial resolutions for regional gravity field inversion using data from space gravimetry missions such as CHAMP, GRACE or GOCE. First, we propose to use the minimal energy spherical spline interpolation to find a good approximation of the geopotential at the orbital altitude of the satellite. Then we explain how to solve Laplace’s equation on the Earth’s exterior to compute a spherical spline to approximate the geopotential at the Earth’s surface. We propose a domain decomposition technique, which can compute an approximation of the minimal energy spherical spline interpolation on the orbital altitude and a multiple star technique to compute the spherical spline approximation by the collocation method. We prove that the spherical spline constructed by means of the domain decomposition technique converges to the minimal energy spline interpolation. We also prove that the modeled spline geopotential is continuous from the satellite altitude down to the Earth’s surface. We have implemented the two computational algorithms and applied them in a numerical experiment using simulated CHAMP geopotential observations computed at satellite altitude (450 km) assuming EGM96 (n max = 90) is the truth model. We then validate our approach by comparing the computed geopotential values using the resulting spherical spline model down to the Earth’s surface, with the truth EGM96 values over several study regions. Our numerical evidence demonstrates that the algorithms produce a viable alternative of regional gravity field solution potentially exploiting the full accuracy of data from space gravimetry missions. The major advantage of our method is that it allows us to compute the geopotential over the regions of interest as well as enhancing the spatial resolution commensurable with the characteristics of satellite coverage, which could not be done using a global spherical harmonic representation. Copyright Springer Numéro de notice : A2009-323 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0283-0 En ligne : https://doi.org/10.1007/s00190-008-0283-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29953
in Journal of geodesy > vol 83 n° 8 (August 2009) . - pp 695 - 708[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09071 SL Revue Centre de documentation Revues en salle Disponible An improved empirical model for the effect of long-period ocean tides on polar motion / Richard S. Gross in Journal of geodesy, vol 83 n° 7 (July 2009)
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Titre : An improved empirical model for the effect of long-period ocean tides on polar motion Type de document : Article/Communication Auteurs : Richard S. Gross, Auteur Année de publication : 2009 Article en page(s) : pp 635 - 644 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] axe de rotation de la Terre
[Termes IGN] marée océanique
[Termes IGN] modèle dynamique
[Termes IGN] moment cinétique atmosphérique
[Termes IGN] moment cinétique océanique
[Termes IGN] mouvement du pôleRésumé : (Auteur) Because the tide-raising potential is symmetric about the Earth’s polar axis it can excite polar motion only by acting upon non-axisymmetric features of the Earth like the oceans. In fact, after removing atmospheric and non-tidal oceanic effects, polar motion excitation observations show a strong fortnightly tidal signal that is not completely explained by existing dynamical and empirical ocean tide models. So a new empirical model for the effect of the termensual (Mtm and mtm), fortnightly (Mf and mf), and monthly (Mm) tides on polar motion is derived here by fitting periodic terms at these tidal frequencies to polar motion excitation observations that span 2 January 1980 to 8 September 2006 and from which atmospheric and non-tidal oceanic effects have been removed. While this new empirical tide model can fully explain the observed fortnightly polar motion excitation signal during this time interval it would still be desirable to have a model for the effect of long-period ocean tides on polar motion that is determined from a dynamical ocean tide model and that is therefore independent of polar motion observations. Copyright Springer Numéro de notice : A2009-303 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0277-y Date de publication en ligne : 28/10/2008 En ligne : https://doi.org/10.1007/s00190-008-0277-y Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29933
in Journal of geodesy > vol 83 n° 7 (July 2009) . - pp 635 - 644[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09061 SL Revue Centre de documentation Revues en salle Disponible Singularity free formulations of the geodetic boundary value problem in gravity-space / G. Austen in Journal of geodesy, vol 83 n° 7 (July 2009)
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Titre : Singularity free formulations of the geodetic boundary value problem in gravity-space Type de document : Article/Communication Auteurs : G. Austen, Auteur ; W. Keller, Auteur Année de publication : 2009 Article en page(s) : pp 645 - 657 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] équation différentielle
[Termes IGN] équation non linéaire
[Termes IGN] force de gravitation
[Termes IGN] problème des valeurs limites
[Termes IGN] simulation numérique
[Termes IGN] valeur limiteRésumé : (Auteur) The idea of transforming the geodetic boundary value problem into a boundary value problem with a fixed boundary dates back to the 1970s of the last century. This transformation was found by F. Sanso and was named as gravity-space transformation. Unfortunately, the advantage of having a fixed boundary for the transformed problem was counterbalanced by the theoretical as well as practical disadvantage of a singularity at the origin. In the present paper two more versions of a gravity-space transformation are investigated, where none of them has a singularity. In both cases the transformed differential equations are nonlinear. Therefore, a special emphasis is laid on the linearized problems and their relationships to the simple Hotine-problem and to the symmetries between both formulations. Finally, in numerical simulation study the accuracy of the solutions of both linearized problems is studied and factors limiting this accuracy are identified. Copyright Springer Numéro de notice : A2009-304 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0278-x En ligne : https://doi.org/10.1007/s00190-008-0278-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29934
in Journal of geodesy > vol 83 n° 7 (July 2009) . - pp 645 - 657[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09061 SL Revue Centre de documentation Revues en salle Disponible Fitting gravimetric geoid models to vertical deflections / Will E. Featherstone in Journal of geodesy, vol 83 n° 6 (June 2009)
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Titre : Fitting gravimetric geoid models to vertical deflections Type de document : Article/Communication Auteurs : Will E. Featherstone, Auteur Année de publication : 2009 Article en page(s) : pp 583 - 589 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Australie
[Termes IGN] déviation de la verticale
[Termes IGN] géoïde gravimétrique
[Termes IGN] géoïde local
[Termes IGN] penteRésumé : (Auteur) Regional gravimetric geoid and quasigeoid models are now commonly fitted to GPS-levelling data, which simultaneously absorbs levelling, GPS and quasi/geoid errors due to their inseparability. We propose that independent vertical deflections are used instead, which are not affected by this inseparability problem. The formulation is set out for geoid slopes and changes in slopes. Application to 1,080 astrogeodetic deflections over Australia for the AUSGeoid98 model shows that it is feasible, but the poor quality of the historical astrogeodetic deflections led to some unrealistic values. Copyright Springer Numéro de notice : A2009-286 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0263-4 En ligne : https://doi.org/10.1007/s00190-008-0263-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29916
in Journal of geodesy > vol 83 n° 6 (June 2009) . - pp 583 - 589[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09051 SL Revue Centre de documentation Revues en salle Disponible Gravity gradient modeling using gravity and DEM / L. Zhu in Journal of geodesy, vol 83 n° 6 (June 2009)
PermalinkRelative gravity measurement campaign during the 7th international comparison of absolute gravimeters (2005) / Z. Jiang in Metrologia, vol 46 n° 3 (June 2009)
PermalinkThe determination of potential difference by the joint application of measured and synthetical gravity data: a case study in Hungary / G. Papp in Journal of geodesy, vol 83 n° 6 (June 2009)
PermalinkPermalinkEffect of the satellite laser ranging network distribution on geocenter motion estimation / Xavier Collilieux in Journal of geophysical research : Solid Earth, Vol 114 n° B4 (April 2009)
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PermalinkGlobal geodetic observing system for geohazards and global change / Hans-Peter Plag in Géosciences, n° 9 (avril 2009)
PermalinkPermalinkPermalinkObservation des eaux continentales depuis l'espace / Anny Cazenave in Géosciences, n° 9 (avril 2009)
PermalinkLes marées terrestres, la dynamique du manteau et la sismicité / Laurent Métivier in Géomatique expert, n° 67 (01/02/2009)
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