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Iterative data assimilation approach for the refinement of marine geoid models using sea surface height and dynamic topography datasets / Sander Varbla in Journal of geodesy, vol 97 n° 3 (March 2023)
[article]
Titre : Iterative data assimilation approach for the refinement of marine geoid models using sea surface height and dynamic topography datasets Type de document : Article/Communication Auteurs : Sander Varbla, Auteur ; Artu Ellmann, Auteur Année de publication : 2023 Article en page(s) : n° 24 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] collocation par moindres carrés
[Termes IGN] données altimétriques
[Termes IGN] geoïde marin
[Termes IGN] hauteurs de mer
[Termes IGN] itération
[Termes IGN] levé gravimétrique
[Termes IGN] simulation hydrodynamiqueRésumé : (auteur) The modelling errors of marine geoid models may reach up to a few decimetres in the shorter wavelength spectrum due to gravity data void areas and/or inaccurate data. Various data acquisition methods can provide sea surface heights more accurately. Similarly, hydrodynamic model data in conjunction with tide gauge readings allow the derivation of reliable dynamic topography. Geometrical marine geoid heights, independent of the usual gravity-based marine geoid models, can be obtained by removing the estimated dynamic topography from sea surface height measurements. This study exploits such geometry information to refine marine geoid models. A data assimilation approach was developed that iteratively combines sea surface height and dynamic topography datasets with an initial gravimetric geoid model. A case study is presented using sea surface heights from shipborne GNSS campaigns and an airborne laser scanning survey for refining the EIGEN-6C4 global geopotential model. Comparisons with a high-resolution regional marine geoid model reveal that the initial discrepancies of up to around two decimetres reduce to sub-decimetre within the study area. It is concluded that the developed iterative data assimilation approach can significantly improve the accuracy of marine geoid models, especially in regions where gravity data are of poor quality or unavailable. Numéro de notice : A2023-157 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-023-01711-7 Date de publication en ligne : 15/03/2023 En ligne : https://doi.org/10.1007/s00190-023-01711-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102846
in Journal of geodesy > vol 97 n° 3 (March 2023) . - n° 24[article]The use of gravity data to determine orthometric heights at the Hong Kong territories / Albertini Nsiah Ababio in Journal of applied geodesy, vol 16 n° 4 (October 2022)
[article]
Titre : The use of gravity data to determine orthometric heights at the Hong Kong territories Type de document : Article/Communication Auteurs : Albertini Nsiah Ababio, Auteur ; Robert Tenzer, Auteur Année de publication : 2022 Article en page(s) : pp 401 - 416 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] altitude orthométrique
[Termes IGN] correction orthométrique
[Termes IGN] Hong-Kong
[Termes IGN] interpolation
[Termes IGN] levé gravimétrique
[Termes IGN] montagne
[Termes IGN] système de référence local
[Vedettes matières IGN] AltimétrieRésumé : (auteur) The Hong Kong Principal Datum (HKPD) is the currently adopted official geodetic vertical datum at the Hong Kong territories. The HKPD is practically realized by heights of levelling benchmarks. The HKPD heights are, however, neither normal nor orthometric. The reason is that heights of levelling benchmarks were determined from precise levelling measurements, but without involving gravity observations along levelling lines. To reduce systematic errors due to disregarding the gravity information along levelling lines, we used terrestrial and marine gravity data to interpolate gravity values at levelling benchmarks in order to compute and apply the orthometric correction to measured levelling height differences. Our results demonstrate the importance of incorporating the gravity information even for a relatively small region but characterized by a rough topography with heights of levelling benchmarks exceeding several hundreds of meters. According to our estimates, the orthometric correction reaches (and even slightly exceeds) ±2 cm, with maxima along levelling lines crossing mountain chains. Numéro de notice : A2022-742 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2022-0012 Date de publication en ligne : 04/08/2022 En ligne : https://doi.org/10.1515/jag-2022-0012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101724
in Journal of applied geodesy > vol 16 n° 4 (October 2022) . - pp 401 - 416[article]Modeling gravimetric signatures of third-degree ocean tides and their detection in superconducting gravimeter records / Roman Sulzbach in Journal of geodesy, vol 96 n° 5 (May 2022)
[article]
Titre : Modeling gravimetric signatures of third-degree ocean tides and their detection in superconducting gravimeter records Type de document : Article/Communication Auteurs : Roman Sulzbach, Auteur ; Hartmut Wziontek, Auteur ; Michael Hart-Davis, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 35 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] données marégraphiques
[Termes IGN] gravimètre supraconducteur
[Termes IGN] levé gravimétrique
[Termes IGN] marée océanique
[Termes IGN] montée du niveau de la mer
[Termes IGN] simulation hydrodynamique
[Termes IGN] surcharge océaniqueRésumé : (auteur) We employ the barotropic, data-unconstrained ocean tide model TiME to derive an atlas for degree-3 tidal constituents including monthly to terdiurnal tidal species. The model is optimized with respect to the tide gauge data set TICON-td that is extended to include the respective tidal constituents of diurnal and higher frequencies. The tide gauge validation shows a root-mean-square (RMS) deviation of 0.9–1.3 mm for the individual species. We further model the load tide-induced gravimetric signals by two means (1) a global load Love number approach and (2) evaluating Greens-integrals at 16 selected locations of superconducting gravimeters. The RMS deviation between the amplitudes derived using both methods is below 0.5 nGal (1 nGal =0.01nms2) when excluding near-coastal gravimeters. Utilizing ETERNA-x, a recently upgraded and reworked tidal analysis software, we additionally derive degree-3 gravimetric tidal constituents for these stations, based on a hypothesis-free wave grouping approach. We demonstrate that this analysis is feasible, yielding amplitude predictions of only a few 10 nGal, and that it agrees with the modeled constituents on a level of 63–80% of the mean signal amplitude. Larger deviations are only found for lowest amplitude signals, near-coastal stations, or shorter and noisier data sets. Numéro de notice : A2022-299 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01609-w Date de publication en ligne : 30/04/2022 En ligne : https://doi.org/10.1007/s00190-022-01609-w Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100511
in Journal of geodesy > vol 96 n° 5 (May 2022) . - n° 35[article]Deep mass redistribution prior to the 2010 Mw 8.8 Maule (Chile) Earthquake revealed by GRACE satellite gravity / Marie Bouih in Earth and planetary science letters, vol 584 (15 April 2022)
[article]
Titre : Deep mass redistribution prior to the 2010 Mw 8.8 Maule (Chile) Earthquake revealed by GRACE satellite gravity Type de document : Article/Communication Auteurs : Marie Bouih , Auteur ; Isabelle Panet , Auteur ; Dominique Remy, Auteur ; Laurent Longuevergne, Auteur ; Sylvain Bonvalot, Auteur Année de publication : 2022 Projets : Université de Paris / Clerici, Christine Conférence : EGU 2022, General Assembly 23/05/2022 27/05/2022 Vienne Autriche OA Abstracts only Article en page(s) : n° 117465 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] Chili
[Termes IGN] déformation de la croute terrestre
[Termes IGN] données GRACE
[Termes IGN] gradient de gravitation
[Termes IGN] jeu de données
[Termes IGN] levé gravimétrique
[Termes IGN] prévention des risques
[Termes IGN] risque naturel
[Termes IGN] séisme
[Termes IGN] signal
[Termes IGN] subduction
[Termes IGN] tectonique des plaquesRésumé : (auteur) Subduction zones megathrust faults constitute a considerable hazard as they produce most of the world's largest earthquakes. However, the role in megathrust earthquake generation exerted by deeper subduction processes remains poorly understood. Here, we analyze the 2003 – 2014 space-time variations of the Earth's gravity gradients derived from three datasets of GRACE geoid models over a large region surrounding the rupture zone of the Mw 8.8 Maule earthquake. In all these datasets, our analysis reveals a large-amplitude gravity gradient signal, progressively increasing in the three months before the earthquake, North of the epicentral area. We show that such signals are equivalent to a water storage decrease over 2 months and cannot be explained by hydrological sources nor artefacts, but rather find origin from mass redistributions within the solid Earth on the continental side of the subduction zone. These gravity gradient variations could be explained by an extensional deformation of the slab around 150-km depth along the Nazca Plate subduction direction, associated with large-scale fluid release. Furthermore, the lateral migration of the gravity signal towards the surface from a low coupling segment around North to the high coupling one in the South suggests that the Mw 8.8 earthquake may have originated from the propagation up to the trench of this deeper slab deformation. Our results highlight the importance of observations of the Earth's time-varying gravity field from satellites in order to probe slow mass redistributions in-depth major plate boundaries and provide new information on dynamic processes in the subduction system, essential to better understand the seismic cycle as a whole. Numéro de notice : A2022-280 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.epsl.2022.117465 En ligne : https://doi.org/10.1016/j.epsl.2022.117465 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100288
in Earth and planetary science letters > vol 584 (15 April 2022) . - n° 117465[article]Applications and challenges of GRACE and GRACE follow-on satellite gravimetry / Jianli Chen in Surveys in Geophysics, vol 43 n° 1 (February 2022)
[article]
Titre : Applications and challenges of GRACE and GRACE follow-on satellite gravimetry Type de document : Article/Communication Auteurs : Jianli Chen, Auteur ; Anny Cazenave, Auteur ; Christoph Dahle, Auteur ; William Llovel, Auteur ; Isabelle Panet , Auteur ; Julia Pfeffer, Auteur ; Lorena Moreira, Auteur Année de publication : 2022 Projets : 3-projet - voir note / Clerici, Christine Article en page(s) : pp 305 - 345 Note générale : bibliographie
This project received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (GRACEFUL Synergy Grant agreement No 855677).Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] champ de gravitation
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] changement climatique
[Termes IGN] cryosphère
[Termes IGN] détection de changement
[Termes IGN] données GRACE
[Termes IGN] gravimétrie spatiale
[Termes IGN] hydrosphère
[Termes IGN] masse
[Termes IGN] niveau de la merRésumé : (auteur) Time-variable gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions have opened up a new avenue of opportunities for studying large-scale mass redistribution and transport in the Earth system. Over the past 19 years, GRACE/GRACE-FO time-variable gravity measurements have been widely used to study mass variations in diferent components of the Earth system, including the hydrosphere, ocean, cryosphere, and solid Earth, and signifcantly improved our understanding of long-term variability of the climate system. We carry out a comprehensive review of GRACE/GRACE-FO satellite gravimetry, time-variable gravity felds, data processing methods, and major applications in several diferent felds, includingterrestrial water storage change, global ocean mass variation, ice sheets and glaciers mass balance, and deformation of the solid Earth. We discuss in detail several major challenges we need to face when using GRACE/GRACE-FO time-variable gravity measurements to study mass changes, and how we should address them. We also discuss the potential of satellite gravimetry in detecting gravitational changes that are believed to originate from the deep Earth. The extended record of GRACE/GRACE-FO gravity series, with expected continuous improvements in the coming years, will lead to a broader range of applications and improve our understanding of both climate change and the Earth system. Numéro de notice : A2022-113 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10712-021-09685-x Date de publication en ligne : 10/01/2022 En ligne : https://doi.org/10.1007/s10712-021-09685-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99631
in Surveys in Geophysics > vol 43 n° 1 (February 2022) . - pp 305 - 345[article]Géophysique / Jacques Dubois (2022)PermalinkGeoid determination through the combined least-squares adjustment of GNSS/levelling/gravity networks – a case study in Linyi, China / Dongmei Guo in Survey review, Vol 53 n° 381 (November 2021)PermalinkJoint inversion of ground gravity data and satellite gravity gradients between Nepal and Bhutan: New insights on structural and seismic segmentation of the Himalayan arc / Rodolphe Cattin in Physics and chemistry of the Earth (A/B/C), vol 123 (October 2021)PermalinkComparison and evaluation of high-resolution marine gravity recovery via sea surface heights or sea surface slopes / Shengjun Zhang in Journal of geodesy, vol 95 n° 6 (June 2021)PermalinkHigh-resolution geoid modeling using least squares modification of Stokes and Hotine formulas in Colorado / Mustafa Serkan Işık in Journal of geodesy, vol 95 n° 5 (May 2021)PermalinkUne nouvelle détermination de l'altitude de l'Everest par le Népal et la Chine / Gavin Schrock in XYZ, n° 166 (mars 2021)PermalinkWhat have we learnt from Icesat on Greenland ice sheet change and what to expect from Icesat 2 / Blaženka Bukač in Geodetski vestnik, vol 65 n° 1 (March - May 2021)PermalinkCharacterization of mass variations in Antarctica in response to climatic fluctuations from space-based gravimetry and radar altimetry data / Athul Kaitheri (2021)PermalinkDéveloppement d’une méthode innovante pour l’ajustement des paramètres internes du système de gravimétrie sous-marine GraviMob / Ossama Kharbou (2021)PermalinkPermalinkFrom space to lithosphere: inversion of the GOCE gravity gradients. Supply to the Earth’s interior study / Matthieu Plasman in Geophysical journal international, vol 223 n° 1 (October 2020)PermalinkIntegration of airborne gravimetry data filtering into residual least-squares collocation: example from the 1 cm geoid experiment / Martin Willberg in Journal of geodesy, vol 94 n° 8 (August 2020)PermalinkUsing quantum optical sensors for determining the Earth’s gravity field from space / Jurgen Müller in Journal of geodesy, vol 94 n° 8 (August 2020)PermalinkThe impact of terrestrial gravity data density on geoid accuracy: case study Bilogora in Croatia / Olga Bjelotomić Oršulić in Survey review, vol 52 n° 373 (July 2020)PermalinkImpact of temperature stabilization on the strapdown airborne gravimetry: a case study in Central Turkey / Mehmet Simav in Journal of geodesy, vol 94 n°4 (April 2020)Permalink40 ans de géodésie à l'IGN (Institut Géographique National rebaptisé en 2012 Institut national de l'information géographique et forestière) : 2ème partie, la géodésie physique / Françoise Duquenne in XYZ, n° 162 (mars 2020)PermalinkUsing real polar ground gravimetry data to solve the GOCE polar gap problem in satellite-only gravity field recovery / Biao Lu in Journal of geodesy, Vol 94 n°3 (March 2020)PermalinkValidation of marine geoid models by utilizing hydrodynamic model and shipborne GNSS profiles / Sander Varbla in Marine geodesy, Vol 43 n° 2 (March 2020)PermalinkApplying iterative method to solving high-order terms of seafloor topography / Diao Fan in Marine geodesy, Vol 43 n° 1 (January 2020)PermalinkEtablissement d’une mesure gravimétrique absolue et d’un gradient vertical d’accélération de pesanteur dans les locaux du Laboratoire national d’essais (LNE) à Paris 15ème / Renaud Degoy (2020)Permalink