Vivi K. Pedersen: LL 22.06.23
Channel: Landscapes Live
Date: 22/06/2023

The influence of surface processes on the solid Earth, ice sheets, and sea level

In this talk I will focus on the influence of surface processes on solid-Earth deformation, ice-sheet behavior, and sea-level changes over Quaternary timescales where erosion and deposition by glaciers and ice sheets have modified Earth’s surface significantly through numerous glacial cycles. These changes in the topography and the volumes of sediments deposited offshore, have caused signifcant isostatic adjustments and local sea-level changes, owning to erosional unloading and depositional loading of the lithosphere. In addition, changes in topography and bathymetry have the potential to influence the flow and the extent of ice sheets, and thus the sea-level equivalent ice volume that can be stored in a given landscape. Unfortunately, few studies have investigated the importance of these geomorphic processes for glacial settings on glacial-interglacial timescales, despite large erosion rates and the inherent importance of sea-level changes for ice-sheet dynamics and stability. 

Here I focus on the North Atlantic margins and explore the importance of these geomorphic processes in the context of the Greenland ice sheet and the former Scandinavian ice sheet. These two margins of the North Atlantic complement each other well as they both hold unique observations. Particularly, I will present some quantitative estimates of erosion-driven uplift in North and North-East Greenland, and assess what this might tell us about early glaciations in these regions. In addition, I will look to Scandinavia to explore the importance of glacial erosion and deposition for solid-Earth deformation and sea level over just a few glacial cycles. Finally, I will show some preliminary results using a dynamic ice-sheet model to explore the influence of landscape evolution for the behavior of the former Scandinavian ice sheet.