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Levelling co-located GNSS and tide gauge stations using GNSS reflectometry / Alvaro Santamaria Gomez in Journal of geodesy, vol 89 n° 3 (March 2015)
[article]
Titre : Levelling co-located GNSS and tide gauge stations using GNSS reflectometry Type de document : Article/Communication Auteurs : Alvaro Santamaria Gomez, Auteur ; Christopher S. Watson, Auteur ; Médéric Gravelle, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 241 - 258 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse comparative
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] marée océanique
[Termes IGN] marégraphe
[Termes IGN] nivellement
[Termes IGN] point de liaison (géodésie)
[Termes IGN] propagation troposphérique
[Termes IGN] rapport signal sur bruit
[Termes IGN] réflectance de surface
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GPSRésumé : (auteur) The GNSS reflectometry technique provides geometric information on the environment surrounding the GNSS antenna including the vertical distance to a reflecting surface. We use sea-surface reflections of GPS signals, recorded as oscillations in signal-to-noise ratio (SNR), to estimate the GNSS to tide gauge (TG) levelling tie, and thus the ellipsoidal heights of the TG. We develop approaches to isolate SNR data dominated by sea-surface reflections and to remove SNR frequency changes caused by the dynamic sea surface. Comparison with in situ levelling at eight sites reveals mean differences at the centimetre level for satellites above 12∘ elevation, with four sites showing differences of 3 cm or smaller. These differences include errors in the in situ levelling, in the antenna calibration model and in the TG measurements, and so represent an upper bound on our technique’s error. Data sampling (1 or 30 s) does not significantly affect the results. We detect systematic errors at the decimetre level related to satellite elevations below 12∘ and to sea-surface height and also differences between results from the L1 and L2 GPS signals larger than 15 cm at two sites. These systematic errors remain unexplained; differences between GPS signals are attributed to receiver-dependent differences in the SNR measurements, while the elevation-dependent error is attributed to unmodelled phase effects such as those caused by tropospheric refraction and sea-surface roughness. Using our approach, we identify a levelling offset of 1.5 cm related to a TG sensor change, illustrating our technique’s value for TG reference monitoring. Numéro de notice : A2015-337 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0784-y Date de publication en ligne : 20/12/2014 En ligne : https://doi.org/10.1007/s00190-014-0784-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76705
in Journal of geodesy > vol 89 n° 3 (March 2015) . - pp 241 - 258[article]De la navigation "à vue" au calcul des longitudes / Jean-Yves Sarazin in Carto, le monde en cartes, n° 28 (mars - avril 2015)
[article]
Titre : De la navigation "à vue" au calcul des longitudes Type de document : Article/Communication Auteurs : Jean-Yves Sarazin, Auteur Année de publication : 2015 Article en page(s) : pp 66 - 71 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Cartographie ancienne
[Termes IGN] carte marine
[Termes IGN] coordonnées géodésiques
[Termes IGN] longitude
[Termes IGN] mer
[Termes IGN] navigation maritimeRésumé : (Auteur) Tous les plus anciens marins de la planète commencèrent leurs périples sans aucune représentation cartographique des distances et des surfaces à parcourir. Ils progressaient le long d'un littoral, en pratiquant par atavisme la navigation "à vue" des amers naturels ou artificiels, des rochers, collines, tours et fanaux. Il fallut attendre le 13ème siècle et la multiplication des relations commerciales entre l'Orient et l'Occident pour qu'apparaissent les premiers schémas des mers traversées. Numéro de notice : A2015-450 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77098
in Carto, le monde en cartes > n° 28 (mars - avril 2015) . - pp 66 - 71[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 154-2015021 SL Revue Centre de documentation Revues en salle Disponible Sequential estimation of surface water mass changes from daily satellite gravimetry data / Guillaume L. Ramilien in Journal of geodesy, vol 89 n° 3 (March 2015)
[article]
Titre : Sequential estimation of surface water mass changes from daily satellite gravimetry data Type de document : Article/Communication Auteurs : Guillaume L. Ramilien, Auteur ; Frédéric Frappart, Auteur ; S. Gratton, Auteur Année de publication : 2015 Article en page(s) : pp 259 - 282 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Amazone (fleuve)
[Termes IGN] Amérique du sud
[Termes IGN] analyse diachronique
[Termes IGN] bande K
[Termes IGN] carte thématique
[Termes IGN] données GRACE
[Termes IGN] estimation statistique
[Termes IGN] filtre de Kalman
[Termes IGN] levé gravimétrique
[Termes IGN] masse d'eau
[Termes IGN] océanographie spatiale
[Termes IGN] variation temporelleRésumé : (auteur) We propose a recursive Kalman filtering approach to map regional spatio-temporal variations of terrestrial water mass over large continental areas, such as South America. Instead of correcting hydrology model outputs by the GRACE observations using a Kalman filter estimation strategy, regional 2-by-2 degree water mass solutions are constructed by integration of daily potential differences deduced from GRACE K-band range rate (KBRR) measurements. Recovery of regional water mass anomaly averages obtained by accumulation of information of daily noise-free simulated GRACE data shows that convergence is relatively fast and yields accurate solutions. In the case of cumulating real GRACE KBRR data contaminated by observational noise, the sequential method of step-by-step integration provides estimates of water mass variation for the period 2004–2011 by considering a set of suitable a priori error uncertainty parameters to stabilize the inversion. Spatial and temporal averages of the Kalman filter solutions over river basin surfaces are consistent with the ones computed using global monthly/10-day GRACE solutions from official providers CSR, GFZ and JPL. They are also highly correlated to in situ records of river discharges (70–95 %), especially for the Obidos station where the total outflow of the Amazon River is measured. The sparse daily coverage of the GRACE satellite tracks limits the time resolution of the regional Kalman filter solutions, and thus the detection of short-term hydrological events. Numéro de notice : A2015-338 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0772-2 Date de publication en ligne : 05/11/2014 En ligne : https://doi.org/10.1007/s00190-014-0772-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76707
in Journal of geodesy > vol 89 n° 3 (March 2015) . - pp 259 - 282[article]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]Empirical model of the gravitational field generated by the oceanic lithosphere / Robert Tenzer in Advances in space research, vol 55 n° 1 ([01/01/2015])
[article]
Titre : Empirical model of the gravitational field generated by the oceanic lithosphere Type de document : Article/Communication Auteurs : Robert Tenzer, Auteur ; W. Chen, Auteur ; Zhourun Ye, Auteur Année de publication : 2015 Article en page(s) : pp 72 - 82 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de gravitation
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] harmonique sphérique
[Termes IGN] isostasie
[Termes IGN] lithosphère
[Termes IGN] modèle empirique
[Termes IGN] océanRésumé : (auteur) We present an empirical model of the gravitational field generated by the oceanic lithosphere computed over the world’s oceans with a spectral resolution complete to a spherical harmonic degree of 180. This gravity model is compiled based on applying methods for a spherical harmonic analysis and synthesis of the global gravity and crustal structure models. The in situ seawater densities and the density samples from ocean-floor drilling sites are utilized in the gravimetric forward modeling of bathymetry and marine sediments. The gravitational signal attributed to the oceanic lithosphere density structure is described empirically in terms of the ocean-floor age and depth. The former is explained by the increasing density with age due to conductive cooling of the oceanic lithosphere. The latter describes the gravitational signature of thermal lithospheric contraction, which is isostatically compensated by ocean deepening. The long-wavelength gravity spectrum reflects mainly the compositional and thermal structures within the sub-lithospheric mantle. We demonstrate that this empirical gravity model reproduces realistically most of the long-to-medium wavelength features of the actual gravity field, except for some systematic discrepancies, especially along continental slopes and large sedimentary accumulations, which cannot be described accurately by applied empirical models. Numéro de notice : A2015-296 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2014.09.023 En ligne : https://doi.org/10.1016/j.asr.2014.09.023 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76456
in Advances in space research > vol 55 n° 1 [01/01/2015] . - pp 72 - 82[article]Rapport Quadriennal 2011-2015 [du] CNFGG [à la] 26e assemblée générale de l'Union Géodésique et Géophysique Internationale / Pierre Hubert (2015)PermalinkVisualisation homogène du littoral à partir de données géographiques hétérogènes spatio-temporelles / Antoine Masse (2015)PermalinkTerrestrial laser scanning as a key element in the integrated monitoring of tidal influences on a twin-tube concrete tunnel / Timothy Nuttens in Photogrammetric record, vol 29 n° 148 (December 2014 - February 2015)PermalinkModelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network / Walaiporn Phonphan in Geocarto international, vol 29 n° 7 - 8 (November - December 2014)PermalinkExtracting tidal frequencies using multivariate harmonic analysis of sea level height time series / AliReza Amiri-Simkooei in Journal of geodesy, vol 88 n° 10 (October 2014)PermalinkCoastal and marine ecological changes and fish cage culture development in Phu Quoc, Vietnam (2001 to 2011) / Diep Thi Hong Nguyen in Geocarto international, vol 29 n° 5 - 6 (August - October 2014)PermalinkDomaine public à parcelliser / Pierre Clergeot in Géomètre, n° 2116 (juillet - août 2014)PermalinkBig scanning on a small scale / Stephen Richardson in GEO: Geoconnexion international, vol 13 n° 6 (june 2014)PermalinkEffect of the processing methodology on satellite altimetry-based global mean sea level rise over the Jason-1 operating period / Olivier Henry in Journal of geodesy, vol 88 n° 4 (April 2014)PermalinkLong-term vertical land motion from double-differenced tide gauge and satellite altimetry data / Alvaro Santamaria Gomez in Journal of geodesy, vol 88 n° 3 (March 2014)Permalink