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Triangulated spherical splines for geopotential reconstruction / M.J. Lai in Journal of geodesy, vol 83 n° 8 (August 2009)
[article]
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)
[article]
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)
[article]
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)
[article]
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)
[article]
Titre : Gravity gradient modeling using gravity and DEM Type de document : Article/Communication Auteurs : L. Zhu, Auteur ; Christopher Jekeli, Auteur Année de publication : 2009 Article en page(s) : pp 557 - 567 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] anomalie de pesanteur
[Termes IGN] collocation par moindres carrés
[Termes IGN] gradient de gravitation
[Termes IGN] gravimétrie aérienne
[Termes IGN] levé gravimétrique
[Termes IGN] modèle de géopotentiel local
[Termes IGN] modèle numérique de terrain
[Termes IGN] problème des valeurs limitesRésumé : (Auteur) A model of the gravity gradient tensor at aircraft altitude is developed from the combination of ground gravity anomaly data and a digital elevation model. The gravity data are processed according to various operational solutions to the boundary-value problem (numerical integration of Stokes’ integral, radial-basis splines, and least-squares collocation). The terrain elevation data are used to reduce free-air anomalies to the geoid and to compute a corresponding indirect effect on the gradients at altitude. We compare the various modeled gradients to airborne gradiometric data and find differences of the order of 10–20 E (SD) for all gradient tensor elements. Our analysis of these differences leads to a conclusion that their source may be primarily measurement error in these particular gradient data. We have thus demonstrated the procedures and the utility of combining ground gravity and elevation data to validate airborne gradiometer systems. Copyright Springer Numéro de notice : A2009-285 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-008-0273-2 En ligne : https://doi.org/10.1007/s00190-008-0273-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29915
in Journal of geodesy > vol 83 n° 6 (June 2009) . - pp 557 - 567[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09051 SL Revue Centre de documentation Revues en salle Disponible Relative 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)PermalinkLes marées terrestres, la dynamique du manteau et la sismicité / Laurent Métivier in Géomatique expert, n° 67 (01/02/2009)PermalinkCalibrage de quelques modèles de géoide dans la zone des collines Albanes (Rome) / Valerio Baiocchi in Géomatique expert, n° 66 (01/01/2009)PermalinkOptima multi-step collocation: application to the space-wise approach for GOCE data analysis / M. Reguzzoni in Journal of geodesy, vol 83 n° 1 (January 2009)PermalinkPhysically consistent system model for the study of the Earth's rotation, surface deformation and gravity field parameters / A. Hense (2009)PermalinkPermalinkPermalinkA study reference frame consistency in recent Earth gravitational models / Christopher Kotsakis in Journal of geodesy, vol 83 n° 1 (January 2009)PermalinkAssessing the accuracy of predicted ocean tide loading displacement values / Nigel Penna in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkOn the explicit determination of stability constants for linearized geodetic boundary value problems / Fernando Sanso in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkPolar motion modeling, analysis, and prediction with time dependent harmonic coefficients / Huseyin Baki Iz in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkThe impact of errors in polar motion and nutation on UT1 determinations from VLBI Intensive observations / Axel Nothnagel in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkVariations in the accuracy of gravity recovery due to ground track variability: GRACE, CHAMP, and GOCE / J. Klokocnik in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkThe gravitational effect of ocean tide loading at high latitude coastal stations in Norway / D.I. Lysaker in Journal of geodesy, vol 82 n° 9 (September 2008)PermalinkA data-driven approach to local gravity field modelling using spherical radial basis functions / R. Klees in Journal of geodesy, vol 82 n° 8 (August 2008)PermalinkRetrieving earthquake signature in GRACE gravity solutions / Olivier de Viron in Geophysical journal international, vol 174 n° 1 (July 2008)PermalinkCorsica SLR positioning campaigns (2002 and 2005) for satellite altimeter calibration missions / Bachir Gourine in Marine geodesy, vol 31 n° 2 (June - September 2008)PermalinkGeoid, sea level and vertical datum of the Arctic improved by ICESAT and GRACE / Henriette Skourup in Geomatica, vol 62 n° 2 (June 2008)PermalinkInteractions terre-atmosphère et rotation de la terre / Olivier de Viron in Géomatique expert, n° 63 (01/06/2008)PermalinkMulti-technique monitoring of ocean tide loading in Northern France / Muriel Llubes in Comptes rendus : Géoscience, vol 340 n° 6 (June 2010)PermalinkGPS estimates of ocean tide loading in NW-France: Determination of ocean tide loading constituents and comparison with a recent ocean tide model / Mathilde Vergnolle in Geophysical journal international, vol 173 n° 2 (May 2008)PermalinkLength-of-day and space-geodetic determination of the Earth's variable gravity field / G. Bourda in Journal of geodesy, vol 82 n° 4-5 (April - May 2008)PermalinkOn the non-uniqueness of local quasi-geoids computed from terrestrial gravity anomalies / I. Prutkin in Journal of geodesy, vol 82 n° 3 (March 2008)PermalinkEffects of topographic-isostatic masses on gravitational functionals at the Earth's surface and at airborne and satellite altitudes / A. Makhloof in Journal of geodesy, vol 82 n° 2 (February 2008)PermalinkPermalinkLe Quasi-géoïde libanais (QGL06) et la référence d'altitude du NGL (RAL 06) / Mohamed Allouche in XYZ, n° 113 (décembre 2007 - février 2008)PermalinkQuasigeoid evaluation with improved levelled height data for Norway / D.I. Lysaker in Journal of geodesy, vol 81 n° 9 (September 2007)PermalinkGeocentric sea-level trend estimates from GPS analyses at relevant tide gauges world-wide / Guy Wöppelmann in Global and Planetary Change, vol 57 n° 3-4 (June 2007)PermalinkPractical geodesy: part 3 The geoid / Huibert-Jan Lekkerkerk in Geoinformatics, vol 10 n° 4 (01/06/2007)PermalinkThe topographic bias by analytical continuation in physical geodesy / Lard Erik Sjöberg in Journal of geodesy, vol 81 n° 5 (May 2007)PermalinkAirborne LaCoste & Romberg gravimetry: a space domain approach / M. Abbasi in Journal of geodesy, vol 81 n° 4 (April 2007)Permalinkn° 143 - 2007 (Bulletin de Bulletin international des marées terrestres) / Association internationale de géodésiePermalinkDetermination of the free core nutation period from tidal gravity observations of the GGP superconducting gravimeter network / B. Ducarme in Journal of geodesy, vol 81 n° 3 (March 2007)PermalinkOfficial geoid undulations model: substitute for nationwide orthometric control network / G. Steinberg in GIM international, vol 21 n° 2 (February 2007)PermalinkThe geopotential value W 0 for specifying the relativistic atomic time scale and a global vertical reference system / M. Bursa in Journal of geodesy, vol 81 n° 2 (February 2007)PermalinkCompensation d'un réseau de gravimétrie mesuré par le Service de Géodésie et de Nivellement de l'Institut Géographique National / J. Vienne (2007)PermalinkPermalinkA data set to test geoid computation methods / Henri Duquenne (01/01/2007)PermalinkEtude des ondelettes multipôles de Poisson / Lâmân Lelégard (2007)PermalinkPermalinkLocal solutions to inverse problems in geodesy: The impact of the noise covariance structure upon the accuracy of estimation / F. Bauer in Journal of geodesy, vol 81 n° 1 (January 2007)PermalinkPermalinkPseudo-stochastic orbit modeling of low earth satellites using the Global Positioning System / Adrian Jäggi (2007)PermalinkRelative campaign during the International Comparison of Absolute Gravimeters ICAG-2005 and the strategy of data treatment combined with the absolute results / Zhiheng Jiang (2007)Permalink