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Auteur C. Siemes |
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Estimation of mass change trends in the Earth’s system on the basis of GRACE satellite data, with application to Greenland / C. Siemes in Journal of geodesy, vol 87 n° 1 (January 2013)
[article]
Titre : Estimation of mass change trends in the Earth’s system on the basis of GRACE satellite data, with application to Greenland Type de document : Article/Communication Auteurs : C. Siemes, Auteur ; Pavel Ditmar, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 69 - 87 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] bilan de masse
[Termes IGN] calotte glaciaire
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GRACE
[Termes IGN] filtre de Wiener
[Termes IGN] gravimétrie spatiale
[Termes IGN] Groenland
[Termes IGN] harmonique sphérique
[Termes IGN] isostasie
[Termes IGN] levé gravimétrique
[Termes IGN] matrice de covarianceRésumé : (Auteur) The Gravity Recovery and Climate Experiment (GRACE) satellite mission measures the Earth’s gravity field since March 2002. We propose a new filtering procedure for post-processing GRACE-based monthly gravity field solutions provided in the form of spherical harmonic coefficients. The procedure is tuned for the optimal estimation of linear trends and other signal components that show a systematic behavior over long time intervals. The key element of the developed methodology is the statistically optimal Wiener-type filter which makes use of the full covariance matrices of noise and signal. The developed methodology is applied to determine the mass balance of the Greenland ice sheet, both per drainage system and integrated, as well as the mass balance of the ice caps on the islands surrounding Greenland. The estimations are performed for three 2-year time intervals (2003–2004, 2005–2006, and 2007–2008), as well as for the 6-year time interval (2003–2008). The study confirms a significant difference in the behavior of the drainage systems over time. The average 6-year rate of mass loss in Greenland is estimated as 165 + 15 Gt/year. The rate of mass loss of the ice caps on Ellesmere Island (together with Devon Island), Baffin Island, Iceland, and Svalbard is found to be 22 + 4, 21 + 6, 17 + 9, and 6 + 2 Gt/year, respectively. All these estimates are corrected for the effect of glacial isostatic adjustment. Numéro de notice : A2013-071 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-012-0580-5 Date de publication en ligne : 12/07/2012 En ligne : https://doi.org/10.1007/s00190-012-0580-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32209
in Journal of geodesy > vol 87 n° 1 (January 2013) . - pp 69 - 87[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2013011 SL Revue Centre de documentation Revues en salle Disponible Monitoring GOCE gradiometer calibration parameters using accelerometer and star sensor data: methodology and first results / C. Siemes in Journal of geodesy, vol 86 n° 8 (August 2012)
[article]
Titre : Monitoring GOCE gradiometer calibration parameters using accelerometer and star sensor data: methodology and first results Type de document : Article/Communication Auteurs : C. Siemes, Auteur ; Roger Haagmans, Auteur ; M. Kern, Auteur ; et al., Auteur Année de publication : 2012 Article en page(s) : pp 629 - 645 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GOCE
[Termes IGN] étalonnage d'instrument
[Termes IGN] GOCE
[Termes IGN] gradient de gravitation
[Termes IGN] gradiomètre
[Termes IGN] série temporelleRésumé : (Auteur) The Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite, launched on 17 March 2009, is designed to measure the Earth’s mean gravity field with unprecedented accuracy at spatial resolutions down to 100 km. The accurate calibration of the gravity gradiometer on-board GOCE is of utmost importance for achieving the mission goals. ESA’s baseline method for the calibration uses star sensor and accelerometer data of a dedicated calibration procedure, which is executed every 2 months. In this paper, we describe a method for monitoring the evolution of calibration parameter during that time. The method works with star sensor and accelerometer data and does not require gravity field models, which distinguishes it from other existing methods. We present time series of calibration parameters estimated from GOCE data from 1 November 2009 to 17 May 2010. The time series confirm drifts in the calibration parameters that are present in the results of other methods, including ESA’s baseline method. Although these drifts are very small, they degrade the gravity gradients, leading to the conclusion that the calibration parameters of the ESA’s baseline method need to be linearly interpolated. Further, we find a correction of -36 * 10-6 for one calibration parameter (in-line differential scale factor of the cross-track gradiometer arm), which improves the gravity gradient performance. The results are validated by investigating the trace of the calibrated gravity gradients and comparing calibrated gravity gradients with reference gradients computed along the GOCE orbit using the ITG-Grace-2010s gravity field model. Numéro de notice : A2012-376 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-012-0545-8 Date de publication en ligne : 22/02/2012 En ligne : https://doi.org/10.1007/s00190-012-0545-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31822
in Journal of geodesy > vol 86 n° 8 (August 2012) . - pp 629 - 645[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 266-2012081 RAB Revue Centre de documentation En réserve L003 Disponible