Solid Earth’s response to climate change in Svalbard monitored by space geodesy

• Main Authors: Tafflet, Alicia, Nicolas, Joëlle, Boy, Jean-Paul, Lemoine, Jean-Michel, Perosanz, Félix, Durand, Frédéric, Koulali, Achraf, Gourillon, Lissa, Baltzer, Agnès, Verdun, Jérôme
• Other Authors: Laboratoire Géomatique et foncier (GeF), Conservatoire National des Arts et Métiers CNAM (CNAM), 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), Centre National d'Études Spatiales Toulouse (CNES), School of Engineering Newcastle, Newcastle University Newcastle, Littoral, Environnement, Télédétection, Géomatique (LETG - Nantes), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDE]Environmental Sciences; Arctic; Svalbard; Svalbard Archipelago; Climate change
• Online Access: https://cnam.hal.science/hal-04681391; https://doi.org/10.5194/egusphere-egu24-11433

International audience The Svalbard archipelago in the Arctic is extremely sensitive to climate change. The resulting redistribution of mass, including recent and past ice melt, induces deformations of the Earth's surface and temporal variations in its gravity field, which can be detected by space geodesy. The cross-comparison of different techniques takes advantage of their complementary temporal and spatial resolutions, helping to distinguish between local, regional and global signals. We analyse more than 20 years of GNSS (Global Navigation Satellite System) satellite 3D positionning solutions at 17 permanent sites. The results are compared with deformations computed from time gravity field variations observed by the space gravimetry missions GRACE (Gravity Recovery and Climate Experiment) and GRACE Follow-On. The mean vertical motion is of about 9 mm/year and can reach 15 mm/year. We then compare these GNSS and GRACE datasets with Little Ice Age (LIA) and Global Isostatic Adjustment (GIA) models as well as with satellite altimetry observations from Cryosat-2 and IceSat-2. We infer the various contributions and quantify the impact of the current climate change on Svalbard. In addition to better estimate the acceleration of the current ice melting we apply an innovative seasonal adjustment method. The results are then discussed in relation to in situ observations.