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Impact of the arc length on GNSS analysis results / Simon Lutz in Journal of geodesy, vol 90 n° 4 (April 2016)
[article]
Titre : Impact of the arc length on GNSS analysis results Type de document : Article/Communication Auteurs : Simon Lutz, Auteur ; Michael Meindl, Auteur ; Peter Steigenberger, Auteur ; Gerhard Beutler, Auteur ; Krzysztof Sosnica, Auteur ; Stefan Schaer, Auteur ; Rolf Dach, Auteur ; Daniel Arnold, Auteur ; Daniela Thaller, Auteur ; Adrian Jäggi, Auteur Année de publication : 2016 Article en page(s) : pp 365 - 378 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] géocentre
[Termes IGN] mouvement du pôle
[Termes IGN] orientation de la Terre
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) Homogeneously reprocessed combined GPS/GLONASS 1- and 3-day solutions from 1994 to 2013, generated by the Center for Orbit Determination in Europe (CODE) in the frame of the second reprocessing campaign REPRO-2 of the International GNSS Service, as well as GPS- and GLONASS-only 1- and 3-day solutions for the years 2009 to 2011 are analyzed to assess the impact of the arc length on the estimated Earth Orientation Parameters (EOP, namely polar motion and length of day), on the geocenter, and on the orbits. The conventional CODE 3-day solutions assume continuity of orbits, polar motion components, and of other parameters at the day boundaries. An experimental 3-day solution, which assumes continuity of the orbits, but independence from day to day for all other parameters, as well as a non-overlapping 3-day solution, is included into our analysis. The time series of EOPs, geocenter coordinates, and orbit misclosures, are analyzed. The long-arc solutions were found to be superior to the 1-day solutions: the RMS values of EOP and geocenter series are typically reduced between 10 and 40 %, except for the polar motion rates, where RMS reductions by factors of 2–3 with respect to the 1-day solutions are achieved for the overlapping and the non-overlapping 3-day solutions. In the low-frequency part of the spectrum, the reduction is even more important. The better performance of the orbits of 3-day solutions with respect to 1-day solutions is also confirmed by the validation with satellite laser ranging. Numéro de notice : A2016-250 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0878-1 Date de publication en ligne : 24/12/2015 En ligne : https://doi.org/10.1007/s00190-015-0878-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80758
in Journal of geodesy > vol 90 n° 4 (April 2016) . - pp 365 - 378[article]Elliptic polarisation of the polar motion excitation / Christian Bizouard in Journal of geodesy, vol 90 n° 2 (February 2016)
[article]
Titre : Elliptic polarisation of the polar motion excitation Type de document : Article/Communication Auteurs : Christian Bizouard, Auteur Année de publication : 2016 Article en page(s) : pp 179 - 188 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] mouvement du pôle
[Termes IGN] rotation de la TerreRésumé : (auteur) Because of its geophysical interpretation, Earth’s polar motion excitation is generally decomposed into prograde (counter-clockwise) and retrograde (clockwise) circular terms at fixed frequency. Yet, these later are commonly considered as specific to the frequency and to the underlying geophysical process, and no study has raised the possibility that they could share features independent from frequency. Complex Fourier Transform permits to determine retrograde and prograde circular terms of the observed excitation and of its atmospheric, oceanic and hydrological counterparts. The total prograde and retrograde parts of these excitations are reconstructed in time domain. Then, complex linear correlation between retrograde and conjugate prograde parts is observed for both the geodetic excitation and the matter term of the hydro-atmospheric excitation. In frequency domain, the ratio of the retrograde circular terms with their corresponding conjugate prograde terms favours specific values: the amplitude ratio follows a probabilistic gamma distribution centred around 1.5 (maximum for 1), and the argument ratio obeys a distribution close to a normal law centred around 2α=160∘. These frequency and time domain characteristics mean an elliptical polarisation towards α=∼80∘ East with an ellipticity of 0.8, mostly resulting from the matter term of the hydro-atmospheric excitation. Whatsoever the frequency band above 0.4 cpd, the hydro-atmospheric matter term tends to be maximal in the geographic areas surrounding the great meridian circle of longitude ∼80∘ or ∼260∘ East. The favoured retrograde/prograde amplitude ratio around 1.5 or equivalently the ellipticity of 0.8 can result from the amplification of pressure waves propagating towards the west by the normal atmospheric mode Ψ13 around 10 days. Numéro de notice : A2016-034 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0864-7 Date de publication en ligne : 12/11/2015 En ligne : https://doi.org/10.1007/s00190-015-0864-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79510
in Journal of geodesy > vol 90 n° 2 (February 2016) . - pp 179 - 188[article]The International DORIS Service (IDS) : Recent developments in preparation for ITRF2013 / Pascal Willis (2016)
Titre : The International DORIS Service (IDS) : Recent developments in preparation for ITRF2013 Type de document : Article/Communication Auteurs : Pascal Willis , Auteur ; Franck G. Lemoine, Auteur ; Guilhem Moreaux, Auteur ; Laurent Soudarin, Auteur ; Pascale Ferrage, Auteur ; J.C. Ries, Auteur ; Michiel Otten, Auteur ; Jérôme Saunier , Auteur ; Carey E. Noll, Auteur ; Richard Biancale, Auteur ; Brian Luzum, Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2016 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 143 Conférence : IAG 2013, Scientific assembly, IAG 150 Years Postdam Allemagne Proceedings Springer Importance : pp 631 - 640 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] données Jason
[Termes IGN] International DORIS Service
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] Jason
[Termes IGN] mouvement du pôleRésumé : (auteur) The International DORIS Service (IDS) was created in 2003 under the umbrella of the International Association of Geodesy (IAG) to foster scientific research related to the French DORIS tracking system and to deliver scientific products, mostly related to the International Earth rotation and Reference systems Service (IERS). We first present some general background related to the DORIS system (current and planned satellites, current tracking network and expected evolution) and to the general IDS organization (from Data Centers, Analysis Centers and Combination Center). Then, we discuss some of the steps recently taken to prepare the IDS submission to ITRF2013 (combined weekly time series based on individual solutions from several Analysis Centers). In particular, recent results obtained from the Analysis Centers and the Combination Center show that improvements can still be made when updating physical models of some DORIS satellites, such as Envisat, Cryosat-2 or Jason-2. The DORIS contribution to ITRF2013 should also benefit from the larger number of ground observations collected by the last generation of DGXX receivers (first instrument being onboard Jason-2 satellite). In particular for polar motion, sub-milliarcsecond accuracy seems now to be achievable. Weekly station positioning internal consistency also seems to be improved with a larger DORIS constellation. Numéro de notice : C2013-051 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1007/1345_2015_164 Date de publication en ligne : 13/08/2015 En ligne : http://dx.doi.org/10.1007/1345_2015_164 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78595 Revisiting the pole tide for and from satellite altimetry / Shailen Desai in Journal of geodesy, vol 89 n° 12 (december 2015)
[article]
Titre : Revisiting the pole tide for and from satellite altimetry Type de document : Article/Communication Auteurs : Shailen Desai, Auteur ; John Wahr, Auteur Année de publication : 2015 Article en page(s) : pp 1233 - 1243 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] altimètre
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] analyse diachronique
[Termes IGN] géocentre
[Termes IGN] marée terrestre
[Termes IGN] masse d'eau
[Termes IGN] masse de la Terre
[Termes IGN] mouvement du pôle
[Termes IGN] surcharge océaniqueRésumé : (auteur) Satellite altimeter sea surface height observations include the geocentric displacements caused by the pole tide, namely the response of the solid Earth and oceans to polar motion. Most users of these data remove these effects using a model that was developed more than 20 years ago. We describe two improvements to the pole tide model for satellite altimeter measurements. Firstly, we recommend an approach that improves the model for the response of the oceans by including the effects of self-gravitation, loading, and mass conservation. Our recommended approach also specifically includes the previously ignored displacement of the solid Earth due to the load of the ocean response, and includes the effects of geocenter motion. Altogether, this improvement amplifies the modeled geocentric pole tide by 15 %, or up to 2 mm of sea surface height displacement. We validate this improvement using two decades of satellite altimeter measurements. Secondly, we recommend that the altimetry pole tide model exclude geocentric sea surface displacements resulting from the long-term drift in polar motion. The response to this particular component of polar motion requires a more rigorous approach than is used by conventional models. We show that erroneously including the response to this component of polar motion in the pole tide model impacts interpretation of regional sea level rise by ±0.25 mm/year. Numéro de notice : A2015-888 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0848-7 Date de publication en ligne : 27/08/2020 En ligne : https://doi.org/10.1007/s00190-015-0848-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79436
in Journal of geodesy > vol 89 n° 12 (december 2015) . - pp 1233 - 1243[article]
[article]
Titre : Theoretical geodesy Type de document : Article/Communication Auteurs : Andrzej Borkowski, Auteur ; Wieslaw Kosek, Auteur Année de publication : 2015 Article en page(s) : pp 261 - 279 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] estimation statistique
[Termes IGN] fiabilité des données
[Termes IGN] mouvement du pôle
[Termes IGN] série temporelleRésumé : (auteur) The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+) that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis.
New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2nd, 3rd and 4th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands.Numéro de notice : A2015--019 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/geocart-2015-0015 En ligne : http://dx.doi.org/10.1515/geocart-2015-0015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80815
in Geodesy and cartography > vol 64 n° 2 (December 2015) . - pp 261 - 279[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)PermalinkIntroduction à l’astronomie de position / Jonathan Chenal (2012)PermalinkIntroduction à l’astronomie de position / Jonathan Chenal (2011)PermalinkRefining DORIS atmospheric drag estimation in preparation of ITRF2008 / Marie-Line Gobinddass in Advances in space research, vol 46 n° 12 (15/12/2010)PermalinkContributions of the French Institut Géographique National (IGN) to the International DORIS Service / Pascal Willis in Advances in space research, vol 45 n° 12 (15/06/2010)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)PermalinkAn improved empirical model for the effect of long-period ocean tides on polar motion / Richard S. Gross in Journal of geodesy, vol 83 n° 7 (July 2009)PermalinkPhysically consistent system model for the study of the Earth's rotation, surface deformation and gravity field parameters / A. Hense (2009)PermalinkPolar motion modeling, analysis, and prediction with time dependent harmonic coefficients / Huseyin Baki Iz in Journal of geodesy, vol 82 n° 12 (December 2008)PermalinkThe impact of errors in polar motion and nutation on UT1 determinations from VLBI Intensive observations / Axel Nothnagel in Journal of geodesy, vol 82 n° 12 (December 2008)Permalink