Reconciling ice marginal, subglacial meltwater, and ice flow landform signatures into a coherent retreat pattern of the last Scandinavian Ice Sheet across Norway, Sweden, and Finland

Retreat patterns of past ice sheets such as the last Scandinavian Ice Sheet (SIS), which glaciated Fennoscandia and northern Europe, can be used to understand ice sheet dynamics in response to climate warming. Many current reconstructions of retreat have been conducted at local to regional scales, which can be difficult to reconcile across ice sheet-scales, and ice-sheet scale reconstructions based on consistent approaches to mapping and data sources are rare. Recently available high-resolution topographic data have allowed a reassessment of the glacial landform signature of Norway, Sweden, and Finland, and an opportunity to reconsider the retreat pattern of the last SIS.

Using the glacial inversion approach, we reconcile our independently mapped datasets of ice marginal landforms, subglacial meltwater routes, and subglacial lineations to produce a coherent ice sheet-scale assessment of ice sheet retreat patterns across Norway, Sweden, and Finland. The retreat pattern reveals diverse styles of retreat, including large arcuate ice lobes on lowland landscapes and topographically constrained outlet glaciers in upland areas. We also identify 19 discrete focal points of retreat, which indicate that the SIS fragmented into multiple smaller ice masses during retreat. Although the warming Last Glacial-Interglacial Transition climate drove deglaciation, we suggest that the detailed pattern of SIS retreat was largely controlled by topographic and glaciodynamic factors, and that topo-climatic factors influenced the distribution of remnant ice caps across Fennoscandia.