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Influence of subdaily model for polar motion on the estimated GPS satellite orbits / Natalia Panafidina in Journal of geodesy, vol 93 n° 2 (February 2019)
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Titre : Influence of subdaily model for polar motion on the estimated GPS satellite orbits Type de document : Article/Communication Auteurs : Natalia Panafidina, Auteur ; Urs Hugentobler, Auteur ; Manuela Seitz, Auteur Année de publication : 2019 Article en page(s) : pp 229 - 240 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] élément orbital
[Termes IGN] erreur systématique
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] marée océanique
[Termes IGN] mouvement du géocentre
[Termes IGN] mouvement du pôle
[Termes IGN] orbite
[Termes IGN] positionnement par GPS
[Termes IGN] rotation de la Terre
[Termes IGN] satellite GPS
[Termes IGN] traitement du signalRésumé : (auteur) In this contribution, it is shown that GPS orbits are able to absorb some diurnal signals in polar motion. The arising implications for the influence of the subdaily pole model on GPS solutions are discussed. Two signals in polar motion can be absorbed by GPS orbits: a retrograde signal with a period of a sidereal day (23 h 56 min 4 s) and a prograde signal with a period matching the revolution period of the GPS satellites in the terrestrial reference frame (23 h 55 min 56 s). We show that the retrograde signal contributes to the absolute orientation of the orbital planes in space and the prograde signal, due to coincidence of its period with the period of revolution of the GPS satellites, contributes to the position of the geocenter for each individual satellite. It is known from previous studies that there are systematic differences between orbital parameters from GPS solutions computed with different subdaily pole models. We show in this paper that this behavior can be explained by the absorption effects in 1-day GPS orbits. Diurnal signals cannot be spectrally separated over a time interval of 1 day. Adjustment of any diurnal prograde or retrograde signal to a subdaily pole time series given by a subdaily model over 24 h will lead to an estimated signal with a nonzero amplitude. Thus, any subdaily pole model used in the processing of space geodetic observations contains a part which corresponds numerically to the discussed prograde signal and a part which corresponds to the retrograde diurnal signal. Different pole models show different amplitudes of the diurnal signals which will be absorbed by the orbits. As a result, GPS orbits computed with different subdaily pole models have systematically different orientation and position in space. Using 1-day GPS solutions over a time span of 13 years (1994–2007), we show that the systematic variations in orbit position and orientation caused by individual tidal terms in polar motion can be well predicted and explained by the suggested mechanism. Numéro de notice : A2019-080 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1153-z Date de publication en ligne : 24/05/2018 En ligne : https://doi.org/10.1007/s00190-018-1153-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92198
in Journal of geodesy > vol 93 n° 2 (February 2019) . - pp 229 - 240[article]Atmospheric angular momentum related to Earth rotation studies: history and modern developments / David A. Salstein (2019)
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Titre : Atmospheric angular momentum related to Earth rotation studies: history and modern developments Type de document : Article/Communication Auteurs : David A. Salstein, Auteur Editeur : Paris, Meudon et Nançay : Observatoire de Paris Année de publication : 2019 Conférence : JSRST 2019, Journées systèmes de référence spatio-temporels, Astrometry, Earth Rotation, and Reference Systems in the GAIA era 07/10/2019 09/10/2019 Paris France OA Proceedings Importance : pp 209 - 213 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] moment cinétique atmosphérique
[Termes IGN] rotation de la TerreRésumé : (auteur) It was noted some time ago that the angular momentum of the atmosphere varies, both regionally as well as in total. Given the conservation of angular momentum in the Earth system, except for known external torques, such variability implies transfer of the angular momentum across the atmosphere’s lower boundary. As nearly all is absorbed by the Earth below, the solid Earth changes its overall rotation from this impact. Due to the large difference between in the moments of inertia of the atmosphere and Earth, relatively big differences in the atmosphere are translated as relatively very small differences in the Earth, measurable as changes in Earth rotation rate, and polar motion. The atmospheric angular momentum (AAM) is that due to the motion of the winds and to the changes in mass distribution, closely related to the atmosphere pressure patterns; its variability in the atmosphere is mirrored in the Earth rotation rate and polar motion. This connection between the global solid Earth properties and the global and regional atmosphere on a number of time scales, especially seasonal and interannual, was much appreciated by Barbara Kolaczek, with Jolanta Nastula, at the Space Research Center in Warsaw, and this was a subject of our collaborative studies. Many calculations were made of atmospheric angular momentum, leading to a service under the Global Geophysical Fluids Center of the IERS based on calculations using both operational meteorological series, determined for weather forecasting purposes, and retrospective analyses of the atmosphere. Theoretical development of the connection between the AAM, Earth rotation/polar motion, and also the angular momentum of the other geophysical fluids occurred at the same time that space-based observations and enhanced computer power were allowing improved skills for both weather analysis and forecasting. Hence better determination of the AAM became possible, which could be used as a measure for forecasting Earth rotation. Today we are looking at the atmosphere in combination with the ocean and other fluids, and also assessing the implications of climate variability on Earth rotation through climate model research. According to models of the Earth system, significant changes in winds appear to be a possible result of climate change, with implications for the Earth rotation parameters. Numéro de notice : C2019-076 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100193 Documents numériques
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Atmospheric angular momentum ... - pdf éditeurAdobe Acrobat PDFCorrelated atom accelerometers for mapping the Earth gravity field from space / Thomas Lévèque (2019)
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Titre : Correlated atom accelerometers for mapping the Earth gravity field from space Type de document : Article/Communication Auteurs : Thomas Lévèque, Auteur ; C. Fallet, Auteur ; Mioara Mandea, Auteur ; Richard Biancale, Auteur ; Jean-Michel Lemoine, Auteur ; Simon Tardivel, Auteur ; Marc Delpech, Auteur ; Guillaume Ramillien, Auteur ; Isabelle Panet , Auteur ; S. Bourgogne, Auteur ; Franck Pereira dos Santos, Auteur ; Ph. Bouyer, Auteur
Editeur : Washington : Society of Photo-Optical Instrumentation Engineers SPIE Année de publication : 2019 Collection : SPIE Proceedings num. 11180 Projets : 1-Pas de projet / Conférence : ICSO 2018, International Conference on Space Optics 09/10/2018 12/10/2018 Chania Grèce Proceedings SPIE Importance : 9 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] accélération
[Termes IGN] accéléromètre
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] mission spatialeRésumé : (auteur) The emergence of quantum technologies, including cold atom based accelerometers, offers an opportunity to improve the performances of space geodesy missions. In this context, CNES initiated an assessment study called GRICE (GRadiométrie à Interféromètres quantiques Corrélés pour l’Espace) in order to evaluate the impact of cold atom technologies to space geodesy and to the end users of the geodetic data. In this paper, we present a specific mission scenario for gravity field mapping based on a twin satellite concept. The mission uses a constellation of two satellites each equipped with a cold atom accelerometer. A laser link measures the distance between the two satellites and couples these two instruments in order to produce a correlated differential acceleration measurement. The main parameters, determining the performances of the payload, have been investigated. In addition, a preliminary study of mass, consumption and volume has been conducted to ensure the onboard feasibility of these instruments. A general study of the satellite architecture, including all the subsystems, has also been realized and is presented here. Numéro de notice : C2018-126 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1117/12.2535951 En ligne : https://doi.org/10.1117/12.2535951 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100045 DPOD2014 : A new DORIS extension of ITRF2014 for precise orbit determination / Guilhem Moreaux in Advances in space research, vol 63 n° 1 (1 January 2019)
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Titre : DPOD2014 : A new DORIS extension of ITRF2014 for precise orbit determination Type de document : Article/Communication Auteurs : Guilhem Moreaux, Auteur ; Pascal Willis , Auteur ; Franck G. Lemoine, Auteur ; Nikita P. Zelensky, Auteur ; Alexandre Couhert, Auteur ; Hanane Ait Lakbir, Auteur ; Pascale Ferrage, Auteur
Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : pp 118 - 138 Note générale : Bibliographie
financement partiel par le CNESLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] combinaison au niveau des observations
[Termes IGN] déformation de la croute terrestre
[Termes IGN] données altimétriques
[Termes IGN] données DORIS
[Termes IGN] Groenland
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] orbitographie
[Termes IGN] rebond post-glaciaire
[Termes IGN] séisme
[Termes IGN] série temporelle
[Termes IGN] vitesseRésumé : (Auteur) To support precise orbit determination of the altimetry missions, the International DORIS Service (IDS) regularly estimates the DPOD (DORIS terrestrial reference frame for Precise Orbit Determination) solution which includes mean positions and velocities of all the DORIS stations. This solution is aligned to the current realization of the International Terrestrial Reference Frame (ITRF) and so, can be seen as a DORIS extension of the ITRF. In 2016, moving to the IDS Combination Center, the DPOD construction scheme changed. The new DPOD solution is produced from a DORIS cumulative position and velocity solution. We present the new methodology used to compute DPOD2014 and its validation procedure. In order to present geophysical applications and interpretations of these results, we show two examples: (1) the Gorkha earthquake (M7.8 – April 2015) generates a 3-D mis-positioning of nearly 55 mm of the EVEB DORIS station at the Everest base camp 90 km from the epicenter. (2) Applying the results the DPOD2014 realization, we show that the most recent vertical velocity of Thule, Greenland is similar to that observed between 2006 and 2010, indicating further ongoing ice mass loss in the Thule region of northwest Greenland. Numéro de notice : A2019-118 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2018.08.043 Date de publication en ligne : 03/09/2018 En ligne : https://doi.org/10.1016/j.asr.2018.08.043 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92643
in Advances in space research > vol 63 n° 1 (1 January 2019) . - pp 118 - 138[article]
Titre : Geospatial analyses of Earth observation (EO) data Type de document : Monographie Auteurs : Antonio Pepe, Éditeur scientifique ; Qing Zhao, Éditeur scientifique Editeur : London [UK] : IntechOpen Année de publication : 2019 Importance : 136 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-1-78984-584-6 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] aérosol
[Termes IGN] analyse spatiale
[Termes IGN] bassin hydrographique
[Termes IGN] bruit (théorie du signal)
[Termes IGN] cartographie géologique
[Termes IGN] changement climatique
[Termes IGN] couleur (variable spectrale)
[Termes IGN] détection de changement
[Termes IGN] données environnementales
[Termes IGN] image hyperspectrale
[Termes IGN] image optique
[Termes IGN] image Sentinel-MSI
[Termes IGN] Italie
[Termes IGN] lac
[Termes IGN] Malawi
[Termes IGN] minéral
[Termes IGN] observation de la Terre
[Termes IGN] risque naturel
[Termes IGN] télédétection spatiale
[Termes IGN] transformation de coordonnées
[Termes IGN] utilisation du solRésumé : (Editeur) Earth Observation and Geospatial Analysis presents current research related to the observation of Earth with sensors operating at various wavelengths. The book describes the use of remote sensing technologies for detecting and monitoring Earth's environmental changes (including surface and atmosphere) and its modifications over time. Chapters cover different research aspects in the framework of remote sensing with a particular emphasis on the use of hyperspectral and optical imageries. The presented experiments concern the study of soil properties, the analysis of land use/land changes, the analysis of bio-aerosols as well as the color of water, the investigation of the scar and samples of a cosmic meteoritic impact, and the theoretical treatment of the operation of spatial coordinate transformation in noisy environments. Overall, this book provides an overview of the adopted methodologies for the accomplishment of geospatial analyses to identify environmental changes due to climate change and natural phenomena. Note de contenu : 1. Application of Topographic Analyses for Mapping Spatial Patterns of Soil Properties
2. Clay Minerals Mapping from Imaging Spectroscopy
3. The Impact of Land Use and Land Cover Changes on the Nkula Dam in the Middle Shire River Catchment, Malawi
4. Advanced Methods for Spatial Analysis of Bioaerosol Long-Range Transport Processes
5. The Color of Water from Space: A Case Study for Italian Lakes from Sentinel-2
6. Bacubirito: An Outstanding Cosmic Sample on Earth
7. Spatial Coordinate Transformations with Noisy DataNuméro de notice : 26673 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Recueil / ouvrage collectif DOI : 10.5772/intechopen.74888 Date de publication en ligne : 27/11/2019 En ligne : https://www.intechopen.com/books/7304 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98967 Improving multi-GNSS ultra-rapid orbit determination for real-time precise point positioning / Xingxing Li in Journal of geodesy, vol 93 n° 1 (January 2019)
PermalinkLEO enhanced Global Navigation Satellite System (LeGNSS) for real-time precise positioning services / Bofeng Li in Advances in space research, vol 63 n° 1 (1 January 2019)
PermalinkPermalinkPermalinkPermalinkPermalinkA spatiotemporal calculus for reasoning about land-use trajectories / Adeline Marinho Maciel in International journal of geographical information science IJGIS, Vol 33 n° 1-2 (January - February 2019)
PermalinkPermalinkUnderstanding of atmospheric systems with efficient numerical methods for observation and prediction / Lei-Ming Ma (2019)
PermalinkGPS satellite clock determination in case of inter-frequency clock biases for triple-frequency precise point positioning / Jiang Guo in Journal of geodesy, vol 92 n° 10 (October 2018)
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