Coastal change in a warming Arctic

• Main Authors: Jensen, Maria, Rubensdotter, Lena, Baltzer, Agnès, Choi, Kyungsik, Garestier, Franck
• Other Authors: The University Centre in Svalbard (UNIS), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2019
• Subjects: [SDE]Environmental Sciences; Arctic; Svalbard; Norway; Adventfjorden; Dicksonfjorden; Braganzavågen; Ice; Isfjord*; Isfjorden; Kongsfjord*; Kongsfjorden; permafrost; Sea ice
• Online Access: https://hal.science/hal-02441434

International audience The coastline of Svalbard is highly dynamic. Coastal erosion, delta progradation, longshore drift and spit migration are parts of the Svalbard coastal environment and contribute to bathymetry changes, risk for infrastructure and cultural heritage, sediment budgets and nutrient fluxes to fjord ecosystems. Hydrological change, permafrost degradation and increased slope instability change rates and sources of sediment supply from land to the coast. Changes in sea ice cover and wave activity affects the distribution of sediment from land to the sea. Until recently no quantification for change existed for the vast majority of the Svalbard coastline. Since 2017 baseline data for the coastal configuration in Isfjorden has been collected, which can now be combined with studies of coastal change on an annual to decadal time scale at representative sites in the Svalbard fjords. The aim of the studies are to quantify coastal change, understand the sediment delivery routes to the coast in different settings and understand the effect of open water for a significant part of the year/all year. This allows us to better predict coastal change both close to settlements and in remote parts of the archipelago, which is relevant for environmental and cultural heritage management. It also provides data on coastal sediment storage and release with implications for nutrient fluxes for marine ecosystem studies as well as for earth system models. We present the ongoing coastal mapping project of Isfjorden (DynaCoast) and the follow up remote sensing project MovingCoasts using SAR images to track high resolution coastal change. We also present close-up examples from the ongoing monitoring of coastal change in Kongsfjorden, Dicksonfjorden, Adventfjorden and Braganzavågen, and discuss how different settings are expected to respond differently to a warming climate scenario.