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Analysis of star camera errors in GRACE data and their impact on monthly gravity field models / Pedro Inácio in Journal of geodesy, vol 89 n° 6 (June 2015)
[article]
Titre : Analysis of star camera errors in GRACE data and their impact on monthly gravity field models Type de document : Article/Communication Auteurs : Pedro Inácio, Auteur ; Pavel Ditmar, Auteur ; Roland Klees, Auteur ; Hassan Hashemi Farahani, Auteur Année de publication : 2015 Article en page(s) : pp 551 - 571 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] acquisition de données
[Termes IGN] analyse diachronique
[Termes IGN] anomalie de pesanteur
[Termes IGN] capteur spatial
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GRACE
[Termes IGN] erreur de mesure
[Termes IGN] impact sur les données
[Termes IGN] modèle d'erreur
[Termes IGN] orientation du capteur
[Termes IGN] propagation d'erreurRésumé : (auteur) Star cameras (SCs) on board the GRACE satellites provide information about the attitudes of the spacecrafts. This information is needed to reduce the K-band ranging data to the centre of mass of the satellites. In this paper, we analyse GRACE SC errors using two months of real data of the primary and secondary SCs. We show that the errors consist of a harmonic component, which is highly correlated with the satellite’s true anomaly, and a stochastic component. We built models of both error components, and use these models for error propagation studies. Firstly, we analyse the propagation of SC errors into inter-satellite accelerations. A spectral analysis reveals that the stochastic component exceeds the harmonic component, except in the 3–10 mHz frequency band. In this band, which contains most of the geophysically relevant signal, the harmonic error component is larger than the random component. Secondly, we propagate SC errors into optimally filtered monthly mass anomaly maps and compare them with the total error. We found that SC errors account for about 18 % of the total error. Moreover, gaps in the SC data series amplify the effect of SC errors by a factor of 5. Finally, an analysis of inter-satellite pointing angles for GRACE data between 2003 and 2010 reveals that inter-satellite ranging errors were exceptionally large during the period February 2003 till May 2003. During these months, SC noise is amplified by a factor of 3 and is a considerable source of errors in monthly GRACE mass anomaly maps. In the context of future satellite gravity missions, the noise models developed in this paper may be valuable for mission performance studies. Numéro de notice : A2015-350 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0797-1 Date de publication en ligne : 03/03/2015 En ligne : https://doi.org/10.1007/s00190-015-0797-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76724
in Journal of geodesy > vol 89 n° 6 (June 2015) . - pp 551 - 571[article]Separation of atmospheric, oceanic and hydrological polar motion excitation mechanisms based on a combination of geometric and gravimetric space observations / F. Göttl in Journal of geodesy, vol 89 n° 4 (April 2015)
[article]
Titre : Separation of atmospheric, oceanic and hydrological polar motion excitation mechanisms based on a combination of geometric and gravimetric space observations Type de document : Article/Communication Auteurs : F. Göttl, Auteur ; M. Schmidt, Auteur ; Florian Seitz, Auteur ; Mathis Blossfeld, Auteur Année de publication : 2015 Article en page(s) : pp 377 - 390 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] atmosphère terrestre
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] géodésie physique
[Termes IGN] masse d'eau
[Termes IGN] mouvement du pôle
[Termes IGN] océanographie spatiale
[Termes IGN] réseau de surveillance géophysique
[Termes IGN] rotation de la TerreRésumé : (auteur) The goal of our study is to determine accurate time series of geophysical Earth rotation excitations to learn more about global dynamic processes in the Earth system. For this purpose, we developed an adjustment model which allows to combine precise observations from space geodetic observation systems, such as Satellite Laser Ranging (SLR), Global Navigation Satellite Systems, Very Long Baseline Interferometry, Doppler Orbit determination and Radiopositioning Integrated on Satellite, satellite altimetry and satellite gravimetry in order to separate geophysical excitation mechanisms of Earth rotation. Three polar motion time series are applied to derive the polar motion excitation functions (integral effect). Furthermore we use five time variable gravity field solutions from Gravity Recovery and Climate Experiment to determine not only the integral mass effect but also the oceanic and hydrological mass effects by applying suitable filter techniques and a land–ocean mask. For comparison the integral mass effect is also derived from degree 2 potential coefficients that are estimated from SLR observations. The oceanic mass effect is also determined from sea level anomalies observed by satellite altimetry by reducing the steric sea level anomalies derived from temperature and salinity fields of the oceans. Due to the combination of all geodetic estimated excitations the weaknesses of the individual processing strategies can be reduced and the technique-specific strengths can be accounted for. The formal errors of the adjusted geodetic solutions are smaller than the RMS differences of the geophysical model solutions. The improved excitation time series can be used to improve the geophysical modeling. Numéro de notice : A2015-343 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0782-0 Date de publication en ligne : 18/12/2014 En ligne : https://doi.org/10.1007/s00190-014-0782-0 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76715
in Journal of geodesy > vol 89 n° 4 (April 2015) . - pp 377 - 390[article]Geological mapping of Jharia Coalfield, India using GRACE EGM2008 gravity data : a vertical derivative approach / Jitendra Vaish in Geocarto international, vol 30 n° 3 - 4 (March - April 2015)
[article]
Titre : Geological mapping of Jharia Coalfield, India using GRACE EGM2008 gravity data : a vertical derivative approach Type de document : Article/Communication Auteurs : Jitendra Vaish, Auteur ; S.K. Pal, Auteur Année de publication : 2015 Article en page(s) : pp 388 - 401 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] carte géologique
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GRACE
[Termes IGN] Earth Gravity Model 2008
[Termes IGN] Inde
[Termes IGN] mine de charbon
[Termes IGN] prospection minéraleRésumé : (Auteur) High-resolution satellite gravity data of gravity recovery and climate experiment (GRACE) generated by Earth Gravity Model-2008 (EGM2008) have been utilised for geological mapping of the Jharia coalfield. The generated GRACE EGM2008 classical gravity data have been processed for estimation of gravity anomaly map. The gravity anomaly map has been enhanced using the first and second Vertical Derivatives techniques. Geological and structural maps of the study area have been overlapped over different derivative maps to analyse the correlation with the subsurface geological structures of the study area. Major distinct geological signatures, on different derivative maps, are correlated well with the existing geological map. Moreover, vertical derivative maps of the gravity data generated from GRACE EGM2008 model provide better agreement and understanding for geological setting of the Jharia coalfield. Numéro de notice : A2015-303 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2014.905637 Date de publication en ligne : 12/05/2014 En ligne : https://doi.org/10.1080/10106049.2014.905637 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76521
in Geocarto international > vol 30 n° 3 - 4 (March - April 2015) . - pp 388 - 401[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Assimilation of GRACE-derived oceanic mass distributions with a global ocean circulation model / J. Saynisch in Journal of geodesy, vol 89 n° 2 (February 2015)
[article]
Titre : Assimilation of GRACE-derived oceanic mass distributions with a global ocean circulation model Type de document : Article/Communication Auteurs : J. Saynisch, Auteur ; I. Bergmann–Wolf, Auteur ; M. Thomas, Auteur Année de publication : 2015 Article en page(s) : pp 121 - 139 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] anomalie de pesanteur
[Termes IGN] assimilation des données
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] correction atmosphérique
[Termes IGN] données GRACE
[Termes IGN] filtre de Kalman
[Termes IGN] masse d'eau
[Termes IGN] océan
[Termes IGN] océanographie spatialeRésumé : (auteur) To study the sub-seasonal distribution and generation of ocean mass anomalies, Gravity Recovery and Climate Experiment (GRACE) observations of daily and monthly resolution are assimilated into a global ocean circulation model with an ensemble-based Kalman-Filter technique. The satellite gravimetry observations are processed to become time-variable fields of ocean mass distribution. Error budgets for the observations and the ocean model’s initial state are estimated which contain the full covariance information. The consistency of the presented approach is demonstrated by increased agreement between GRACE observations and the ocean model. Furthermore, the simulations are compared with independent observations from 54 bottom pressure recorders. The assimilation improves the agreement to high-latitude recorders by up to 2 hPa. The improvements are caused by assimilation-induced changes in the atmospheric wind forcing, i.e., quantities not directly observed by GRACE. Finally, the use of the developed Kalman-Filter approach as a destriping filter to remove artificial noise contaminating the GRACE observations is presented Numéro de notice : A2015-332 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0766-0 Date de publication en ligne : 11/10/2014 En ligne : https://doi.org/10.1007/s00190-014-0766-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76657
in Journal of geodesy > vol 89 n° 2 (February 2015) . - pp 121 - 139[article]Consistent estimates of the dynamic figure parameters of the Earth / Wei Chen in Journal of geodesy, vol 89 n° 2 (February 2015)
[article]
Titre : Consistent estimates of the dynamic figure parameters of the Earth Type de document : Article/Communication Auteurs : Wei Chen, Auteur ; Jiancheng Li, Auteur ; Jim Ray, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 179 - 188 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] ellipsoïde (géodésie)
[Termes IGN] figure de la Terre
[Termes IGN] masse de la Terre
[Termes IGN] moment d'inertieRésumé : (auteur) The Earth’s dynamic figure parameters, namely the principal moments of inertia and dynamic ellipticities of the whole Earth, the fluid outer core and the solid inner core, are fundamental parameters for geodetic, geophysical and astronomical studies. This study aims to re-estimate the mass and the dynamic figure parameters of the Earth on the basis of some global gravity models (EGM2008, EIGEN-6C and EIGEN-6C2) recently released with unprecedented accuracies, as well as an improved value of the gravitational constant G recommended by the Committee on Data for Science and Technology (CODATA). With the potential coefficients of EGM2008, EIGEN-6C and EIGEN-6C2 rescaled to be consistent with the IAU (International Astronomical Union) and IAG (International Association of Geodesy) numerical standards, and other values of relevant parameters also being consistent with those numerical standards, we have obtained consistent estimates of the dynamic figure parameters of the stratified Earth using the theory described in Chen and Shen (J Geophys Res 115:B12419 2010). Our preferred principal moments of inertia for the whole Earth are A=(80,085.1±9.6)×1033 kg m2,B=(80,086.8±9.6)×1033 kg m2, and C=(80,349.0±9.6)×1033 kg m2, respectively, the accuracies being limited by the uncertainties of G and e (dynamic ellipticity of the whole Earth). Numéro de notice : A2015-333 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0768-y Date de publication en ligne : 29/10/2014 En ligne : https://doi.org/10.1007/s00190-014-0768-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76658
in Journal of geodesy > vol 89 n° 2 (February 2015) . - pp 179 - 188[article]Gravity field processing with enhanced numerical precision for LL-SST missions / Ilias Daras in Journal of geodesy, vol 89 n° 2 (February 2015)PermalinkDetermination of precise gravity field for the CLIC feasibility studies / Sébastien Guillaume (2015)PermalinkEmpirical model of the gravitational field generated by the oceanic lithosphere / Robert Tenzer in Advances in space research, vol 55 n° 1 ([01/01/2015])PermalinkGOCE: assessment of GPS-only gravity field determination / Adrian Jäggi in Journal of geodesy, vol 89 n° 1 (January 2015)PermalinkGravité de la Terre : des mesures aux modèles, une image de la dynamique interne / Isabelle Panet (2015)PermalinkPermalinkPermalinkAnnual crop type classification of the US great plains for 2000 to 20011 / Daniel M. Howard in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 6 (June 2014)PermalinkPermalinkModélisation numérique du champ de gravité produit par une structure géologique arbitraire / Clément Roussel in XYZ, n° 139 (juin - août 2014)Permalink