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Auteur Blaise Girard |
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Integration of corner reflectors for the monitoring of mountain glacier areas with Sentinel-1 time series / Matthias Jauvin in Remote sensing, vol 11 n° 8 (August 2019)
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Titre : Integration of corner reflectors for the monitoring of mountain glacier areas with Sentinel-1 time series Type de document : Article/Communication Auteurs : Matthias Jauvin, Auteur ; Yajing Yan, Auteur ; Emmanuel Trouvé, Auteur ; Bénédicte Fruneau , Auteur ; Michel Gay, Auteur ; Blaise Girard, Auteur
Année de publication : 2019 Projets : 3-projet - voir note / Article en page(s) : n° 988 Note générale : bibliographie
The authors would like to thank Antoine Rabatel (Univ. Grenoble Alpes, I.G.E.) for having provided DSM LiDAR-based, acquired as part of the project European Facility for Airborne Research Transnational Access (EUFAR TA, EU FP7 Integrating Activity)—project ISOTHERM (Ice, SnOw vegeTation HypERspectral Measurements) that he has led. The authors would also like to thank the French National Geographic Institute (IGN) for providing the DEM.Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Alpes
[Termes IGN] chambre anéchoïque
[Termes IGN] coin réflecteur
[Termes IGN] erreur de phase
[Termes IGN] faille géologique
[Termes IGN] glacier d'Argentière
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SAR
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] moraine
[Termes IGN] pente
[Termes IGN] prévention des risques
[Termes IGN] rétrodiffusion
[Termes IGN] surface équivalente radar
[Termes IGN] tectoniqueRésumé : (auteur) Glacier flow and slope instabilities in Alpine mountain areas represent a hazard issue. Sentinel-1 satellites provide regular Synthetic Aperture Radar (SAR) acquisitions that are potentially useful to monitor these areas, but they can be affected by temporal decorrelation due to rapid changes in the surface. The application of interferometric synthetic aperture radar (InSAR) therefore seems difficult due to loss of coherence. On the other hand, Corner Reflectors (CR) can be used as coherent targets in SAR images for accurate displacement measurement thanks to their strong backscattering property and temporal stability. The use of CRs in multi-temporal InSAR analysis in Alpine mountain areas can thus be beneficial. In this study, we present a comparison between triangular and rectangular CRs, based on Radar Cross Section (RCS) measurements in an anechoic chamber and on long-term experiments over the Argentière glacier and the surrounding slopes and moraine. The visibility in both summer and winter of 10 CRs installed on the test site was investigated. As this area is exposed to heavy precipitation including snow falls, two perforated CRs were tested. The amplitude stability and the phase error of each CR were estimated. A precise tracking of two CRs installed at the glacier surface was also able to measure the displacement of the Argentière glacier, giving results close to previous GPS measurements. Furthermore, a Persistent Scatterer Interferometry (PSI) study was conducted, using the most stable CR as reference point to estimate slope instabilities, which led to the identification of an area corresponding to a tectonic fault called “Faille de l’angle”. The precise absolute locations of the CRs were successfully estimated and PS heights were compared with a LiDAR-based (Light Detection And Ranging) digital elevation model (DEM) and GPS measurements. Numéro de notice : A2019-627 Affiliation des auteurs : UPEM-LASTIG+Ext (2016-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs11080988 Date de publication en ligne : 25/04/2019 En ligne : https://doi.org/10.3390/rs11080988 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95363
in Remote sensing > vol 11 n° 8 (August 2019) . - n° 988[article]