Sea-level rise is one of the major challenges to be faced by mankind in the oncoming decades. The final aim of our proposal is to contribute to the improvement of the estimates of the current contribution of glaciers to sea-level rise, and the prediction of its future contribution under a changing climate. In previous projects by our research team we mostly focused on the modelling of glacier dynamics (including iceberg calving processes), and on the estimate of ice discharge to the ocean from the South Shetland Islands glaciers, Antarctica. The newly proposed project complements our previous research by focusing on the modelling of the water circulation in the proglaciar fjords of tidewater glaciers located both in Svalbard, Arctic, and in the South Shetland Islands. This fjord circulation model will be coupled with the available glacier dynamics model to calculate submarine melt rates at the glacier front, iceberg calving rates and front position changes. The coupled model will include subglacial discharge to the fjord of meltwater generated at the glacier surface and percolated to the glacier bed. The calculation of surface melt will require regional climate modelling and dynamical downscaling of the modelled data.
Using satellite remotely-sensed glacier velocities and ice thicknesses retrieved from ground-penetrating radar, we will make estimates of the glacier mass losses by frontal ablation, which encompasses the losses by iceberg calving and by submarine melting at the front of marine-terminating. The melt rates calculated by the coupled glacier-fjord system will then be used to estimate the partitioning of the frontal ablation into its two main components. Knowing the shares of the mass losses by these two processes is crucial for the projections of volume evolution of glaciers under given climate scenarios.
Focusing on both the Arctic region (Svalbard) and Antarctica (South Shetland Islands) gives to our approach a rich and most interesting bi-polar perspective, since the ice masses of the high Arctic islands and those of the islands in the periphery of the Antarctic Peninsula share many common characteristics in terms of thermo-hydrological regime, glacier basin size or ice thickness.