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Ocean loading effects on the prediction of Antarctic glacial isostatic uplift and gravity rates / K. Simon in Journal of geodesy, vol 84 n° 5 (May 2010)
[article]
Titre : Ocean loading effects on the prediction of Antarctic glacial isostatic uplift and gravity rates Type de document : Article/Communication Auteurs : K. Simon, Auteur ; T. James, Auteur ; Eric Ivins, Auteur Année de publication : 2010 Article en page(s) : pp 305 - 317 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Antarctique
[Termes IGN] champ de pesanteur local
[Termes IGN] déformation de la croute terrestre
[Termes IGN] données GRACE
[Termes IGN] isostasie
[Termes IGN] positionnement par GPS
[Termes IGN] surcharge océaniqueRésumé : (Auteur) The effect of regional ocean loading on predicted rates of crustal uplift and gravitational change due to glacial isostatic adjustment (GIA) is determined for Antarctica. The effect is found to be significant for the ICE-3G and ICE-5G loading histories (up to -8 mm/year and -3 mm/year change in uplift rate and -3 cm/year and -1 cm/year equivalent water height change (EWHC) of surface mass, respectively). The effect is smaller (+1 mm/year; +0.25 cm/year) for the IJ05 loading history. The impact of ocean loading on the rate of change of the long-wavelength zonal harmonics of the Earth’s gravitational field is also significantly smaller for IJ05 than ICE-3G. A simple analytical formula is derived that is accurate to about 3% in a root-mean-square sense that relates predicted or observed gravitational change at the surface of the Earth (r = a) to the EWHC. A fundamental difference in the definition of the load histories accounts for the differing sensitivities to ocean loading. IJ05 defines its surface load history relative to the present-day surface load, rather than specifying an absolute loading history, and thus implicitly approximates the temporal and spatial mass exchange between grounded ice and open ocean. In contrast, ICE-3G and ICE-5G specify an absolute load history and explicit regional ocean loading substantially perturbs predicted GIA rates. Conclusions of previous studies that used IJ05 predictions without ocean loading are relatively robust. Numéro de notice : A2010-183 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-010-0368-4 Date de publication en ligne : 12/02/2010 En ligne : https://doi.org/10.1007/s00190-010-0368-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30378
in Journal of geodesy > vol 84 n° 5 (May 2010) . - pp 305 - 317[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2010051 SL Revue Centre de documentation Revues en salle Disponible Mantle dynamics, geoid, inertia and TPW since 120 Myr / Hélène Rouby in Earth and planetary science letters, vol 292 n° 3-4 (April 2010)
[article]
Titre : Mantle dynamics, geoid, inertia and TPW since 120 Myr Type de document : Article/Communication Auteurs : Hélène Rouby , Auteur Année de publication : 2010 Article en page(s) : pp 301 - 311 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] géoïde terrestre
[Termes IGN] manteau terrestre
[Termes IGN] moment d'inertie
[Termes IGN] oscillation
[Termes IGN] rotation de la TerreRésumé : (auteur) We investigate the effect of internal masses redistributions on the position of the Earth rotational pole for the last 120 Myr. We use a geodynamic model based on plate reconstructions that estimates the location and rate of subducted slabs under the assumption that they sink vertically into the mantle (Ricard et al., 1993b). Our model also takes into account the effect of large-scale upwellings (domes) derived from an analysis of seismic tomography. Their location is assumed to remain stable with time. We then compute the geoid associated with the time-dependent mantle density heterogeneities. In order to reconcile the computed and observed geoids, we investigate the influence of the depth down to which the subducted Pacific plates beneath the Americas present a significant density contrast with respect to the surrounding mantle on the present-day geoid, and propose a plate model in which we obtain a variance reduction greater than 0.9 for the degree 2. We show that the vertical oscillation of domes within mantle only modulates the amplitude of the associated geoid. The temporal variation of the mantle density heterogeneities is consequently essentially due to changes in the subduction history. The temporal evolution of the Principal Inertia Axis (PIA) of the Earth derived from our model (the rotational axis is aligned to the maximum PIA) is then investigated, and finally compared to estimations of TPW. Both the maximum and intermediate PIAs have moved in a plane perpendicular to Africa, along a circle corresponding to the low of geoid induced by subduction around the Pacific. The minimum PIA seems to be relatively stable since 120 Myr, and close to the maximum degree 2 geoid high under Africa. This can account for observed TPW or African APW in the last 200 Myr. Numéro de notice : A2010-697 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.epsl.2010.01.033 En ligne : https://doi.org/10.1016/j.epsl.2010.01.033 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102049
in Earth and planetary science letters > vol 292 n° 3-4 (April 2010) . - pp 301 - 311[article]Construction of spherical harmonic series for the potential derivatives of arbitrary orders in the geocentric Earth-fixed reference frame / M. Petrovskaya in Journal of geodesy, vol 84 n° 3 (March 2010)
[article]
Titre : Construction of spherical harmonic series for the potential derivatives of arbitrary orders in the geocentric Earth-fixed reference frame Type de document : Article/Communication Auteurs : M. Petrovskaya, Auteur ; A. Vershkov, Auteur Année de publication : 2010 Article en page(s) : pp 165 - 178 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur local
[Termes IGN] coordonnées cartésiennes géocentriques
[Termes IGN] déviation de la verticale
[Termes IGN] Earth Gravity Model 2008
[Termes IGN] harmonique sphérique
[Termes IGN] repère de référence
[Termes IGN] trièdre local
[Termes IGN] varianceRésumé : (Auteur) The derivatives of the Earth gravitational potential are considered in the global Cartesian Earth-fixed reference frame. Spherical harmonic series are constructed for the potential derivatives of the first and second orders on the basis of a general expression of Cunningham (Celest Mech 2:207–216, 1970) for arbitrary order derivatives of a spherical harmonic. A common structure of the series for the potential and its first- and second-order derivatives allows to develop a general procedure for constructing similar series for the potential derivatives of arbitrary orders. The coefficients of the derivatives are defined by means of recurrence relations in which a coefficient of a certain order derivative is a linear function of two coefficients of a preceding order derivative. The coefficients of the second-order derivatives are also presented as explicit functions of three coefficients of the potential. On the basis of the geopotential model EGM2008, the spherical harmonic coefficients are calculated for the first-, second-, and some third-order derivatives of the disturbing potential T, representing the full potential V, after eliminating from it the zero- and first-degree harmonics. The coefficients of two lowest degrees in the series for the derivatives of T are presented. The corresponding degree variances are estimated. The obtained results can be applied for solving various problems of satellite geodesy and celestial mechanics. Copyright Springer Numéro de notice : A2010-155 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0353-y Date de publication en ligne : 10/11/2009 En ligne : https://doi.org/10.1007/s00190-009-0353-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30350
in Journal of geodesy > vol 84 n° 3 (March 2010) . - pp 165 - 178[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2010031 SL Revue Centre de documentation Revues en salle Disponible Establishment of an empirical Geoid Model for a small geographic area: a case study of Port Harcourt, Nigeria / J. Olaleye in SaLIS Surveying and land information science, vol 70 n° 1 (Spring 2010)
[article]
Titre : Establishment of an empirical Geoid Model for a small geographic area: a case study of Port Harcourt, Nigeria Type de document : Article/Communication Auteurs : J. Olaleye, Auteur ; K. Aleem, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : pp 39 - 48 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] altitude orthométrique
[Termes IGN] géoïde local
[Termes IGN] Nigéria
[Termes IGN] port
[Termes IGN] système de référence localRésumé : (Auteur) It is well known that the determination of the geoid model especially by the classical gravimetric approach is not a simple task. Consequently, an empirical method is often adopted for a small geographic area. This approach is especially useful because of its simplicity, accessibility to local surveyors, and its adequacy for many applications involving the conversion of World Geodetic System 1984 (WGS 84) GPS heights to a local height reference system based on the Mean Sea Level (MSL). This paper details the procedures and processes used to establish, validate, and consider the statistical significance of a predictive geoid model for a small geographic area. The model is based on data acquired within the central areas of the Port Harcourt metropolis in southern Nigeria. The MSL benchmark of the Nigerian Ports Authority (NPA) in Port Harcourt, which was established during the colonial administration, served as the reference datum. Copyright SaLIS Numéro de notice : A2010-160 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83713
in SaLIS Surveying and land information science > vol 70 n° 1 (Spring 2010) . - pp 39 - 48[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 121-2010011 RAB Revue Centre de documentation En réserve L003 Disponible Prediction of vertical deflections from high-degree spherical harmonic synthesis and residual terrain model data / C. Hirt in Journal of geodesy, vol 84 n° 3 (March 2010)
[article]
Titre : Prediction of vertical deflections from high-degree spherical harmonic synthesis and residual terrain model data Type de document : Article/Communication Auteurs : C. Hirt, Auteur Année de publication : 2010 Article en page(s) : pp 179 - 190 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Allemagne
[Termes IGN] Alpes centrales
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] déviation de la verticale
[Termes IGN] Earth Gravity Model 2008
[Termes IGN] harmonique sphérique
[Termes IGN] MNS SRTM
[Termes IGN] modèle de géopotentiel
[Termes IGN] modèle de géopotentiel local
[Termes IGN] modèle numérique de terrain
[Termes IGN] Suisse
[Termes IGN] valeur efficaceRésumé : (Auteur) This study demonstrates that in mountainous areas the use of residual terrain model (RTM) data significantly improves the accuracy of vertical deflections obtained from high-degree spherical harmonic synthesis. The new Earth gravitational model EGM2008 is used to compute vertical deflections up to a spherical harmonic degree of 2,160. RTM data can be constructed as difference between high-resolution Shuttle Radar Topography Mission (SRTM) elevation data and the terrain model DTM2006.0 (a spherical harmonic terrain model that complements EGM2008) providing the long-wavelength reference surface. Because these RTM elevations imply most of the gravity field signal beyond spherical harmonic degree of 2,160, they can be used to augment EGM2008 vertical deflection predictions in the very high spherical harmonic degrees. In two mountainous test areas—the German and the Swiss Alps—the combined use of EGM2008 and RTM data was successfully tested at 223 stations with high-precision astrogeodetic vertical deflections from recent zenith camera observations (accuracy of about 0.1 arc seconds) available. The comparison of EGM2008 vertical deflections with the ground-truth astrogeodetic observations shows root mean square (RMS) values (from differences) of 3.5 arc seconds for È and 3.2 arc seconds for È , respectively. Using a combination of EGM2008 and RTM data for the prediction of vertical deflections considerably reduces the RMS values to the level of 0.8 arc seconds for both vertical deflection components, which is a significant improvement of about 75%. Density anomalies of the real topography with respect to the residual model topography are one factor limiting the accuracy of the approach. The proposed technique for vertical deflection predictions is based on three publicly available data sets: (1) EGM2008, (2) DTM2006.0 and (3) SRTM elevation data. This allows replication of the approach for improving the accuracy of EGM2008 vertical deflection predictions in regions with a rough topography or for improved validation of EGM2008 and future high-degree spherical harmonic models by means of independent ground truth data. Numéro de notice : A2010-156 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0354-x Date de publication en ligne : 12/11/2009 En ligne : https://doi.org/10.1007/s00190-009-0354-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30351
in Journal of geodesy > vol 84 n° 3 (March 2010) . - pp 179 - 190[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2010031 SL Revue Centre de documentation Revues en salle Disponible A bias-free geodetic boundary value problem approach to height datum unification / Alireza A. Ardalan in Journal of geodesy, vol 84 n° 2 (February 2010)PermalinkFinite element method for solving geodetic boundary value problems / Z. Faskova in Journal of geodesy, vol 84 n° 2 (February 2010)PermalinkEtude des erreurs systématiques liées à la détermination du géocentre par les mesures DORIS / Marie-Line Gobinddass (2010)PermalinkFundamental gravity network of the Republic Croatia in the function of control and improving of national and European geoid model / I. Grgic (01/01/2010)PermalinkGlobal gravity field determination using the GPS measurements made onboard the low Earth orbiting satellite CHAMP / Lars Prange (2010)PermalinkPreliminary works on creation of the new geoid model HRG2009 / I. Grgic (01/01/2010)PermalinkPermalinkRelevés de température au marégraphe de Marseille / Alain Coulomb in Comptes rendus : Géoscience, vol 342 n° 1 (janvier 2010)PermalinkTransformation of amplitudes and frequencies of precession and nutation of the earth’s rotation vector to amplitudes and frequencies of diurnal polar motion / Bernd Richter in Journal of geodesy, vol 84 n° 1 (January 2010)PermalinkClassical globally reflected gravity field determination in modern locally oriented multiscale framework / W. Freeden in Journal of geodesy, vol 83 n° 12 (December 2009)PermalinkEl nuevo modelo de Geoide para España EGM08-REDNAP / José Antonio Sanchez Sobrino in Topografia y cartografia, vol 26 n° 155 (01/12/2009)PermalinkUsing gravity and topography-implied anomalies to assess data requirements for precise geoid computation / Christopher Jekeli in Journal of geodesy, vol 83 n° 12 (December 2009)PermalinkWavelet modeling of the gravity field over Japan / Isabelle Panet in Bulletin of the Geographical survey institute, vol 57 (December 2009)PermalinkEfficient propagation of error covariance matrices of gravitational models: application to GRACE and GOCE / Georges Balmino in Journal of geodesy, vol 83 n° 10 (October 2009)PermalinkGeocenter variations derived from GPS tracking of the GRACE satellites / Z. Kang in Journal of geodesy, vol 83 n° 10 (October 2009)PermalinkLocal multi-polar expansions in potential field modeling / B. Minchev in Earth, Planets and Space, vol 61 n° 10 (October 2009)PermalinkOn the topographic bias in geoid determination by the external gravity field / Lard Erik Sjöberg in Journal of geodesy, vol 83 n° 10 (October 2009)PermalinkRecursive algorithms for the computation of the potential harmonic coefficients of a constant density polyhedron / Dimitrios Tsoulis in Journal of geodesy, vol 83 n° 10 (October 2009)PermalinkDétermination du géoïde gravimétrique au nord de l'Algérie : méthodes de Stokes-Helmert / N. Zekkour in Bulletin des sciences géographiques, n° 24 (Septembre 2009)PermalinkGeoid and high resolution sea surface topography modelling in the mediterranean from gravimetry, altimetry and GOCE data: evaluation by simulation / R. Barzaghi in Journal of geodesy, vol 83 n° 8 (August 2009)Permalink