Monitoring ice-calving at the Astrolabe glacier (Antarctica) with seismological and Sentinel-2 satellite data

• Main Authors: Provost, Floriane, Malet, Jean-Philippe, Zigone, Dimitri, Le Meur, Emmanuel, Hibert, Clément
• Other Authors: Université Laval Québec (ULaval), Institut Terre Environnement Strasbourg (ITES), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Résif
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2021
• Subjects: RESIF; Seismology; Sismologie; [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; Antarctic; Dumont d'Urville; Dumont-d'Urville; Terre Adélie; Terre-Adélie; Astrolabe; Astrolabe Glacier; Antarc*; Antarctica; Ice Sheet; Ice Shelf; Sea ice; Tidewater
• Online Access: https://hal.archives-ouvertes.fr/hal-03442663; https://hal.archives-ouvertes.fr/hal-03442663/document; https://hal.archives-ouvertes.fr/hal-03442663/file/Resif2021_1Slide_Astrolabe_Provost.pdf

International audience Better understanding the global (e.g. ice mass balance, ice motion) and local (e.g. fissures and calving processes, basal melting, sea-ice interactions) dynamics of tidewater Antarctic outlet glaciers is of paramount importance to simulate the ice-sheet response to global warming. The Astrolable glacier is located in Terre Adélie (140°E, 67°S) near the Dumont d'Urville French research station. Recently, a large fissure of around 3km has been observed in the western shore of the glacier which could lead to a calving of ca. 28km2. We used two monitoring techniques: optical remote sensing and seismology to analyze changes in the activity of the glacier. We computed the surface velocity and strain rates from time series of multispectral Sentinel-2 imagery. The joint analysis of the seismological data and the velocity and strain maps are discussed with the recent evolution of the ice-shelf. The strain maps show complex patterns of extension and compression areas with a seasonal increase during the summer months. The number of calving events significantly increased during 2016-2021 in comparison with the period 2012-2016.