Geomorphological characterisation, pattern, and distribution of ice-margin positions of the former Scandinavian Ice Sheet

Retreating ice sheets leave behind rich landform records which can be used to understand glaciological processes and the responses of ice sheets to warming climates. Ice-marginal landforms are formed along glacier margins, and their distribution on the beds of palaeo-ice sheets can be used to reconstruct former ice-margin positions. Here we scrutinised high-resolution (1–2 m/pixel) digital terrain models across Norway, Sweden, and Finland, applying a consistent approach to observe ice-marginal landforms and then synthesising these to reconstruct former ice-margin positions of the Scandinavian Ice Sheet. We present a map of ∼51,000 pieces of ice marginal evidence defined by assemblages of landforms. Each ice margin is categorised by the dominant landform type that defines it: moraines <250 m and > 250 m wide, De Geer moraines, hummocky moraines, ice-marginal meltwater channels, or glaciofluvial fans and deltas. The distribution of the landform type that defines each ice margin is found to vary across the ice sheet. We investigate these spatial patterns and suggest; i) sediment cover controls the location of ice-margin positions interpreted from meltwater channels; ii) there is a climatic control on the formation of ice-margin positions interpreted from hummocky moraines; iii) moraine size is influenced by the presence or absence of a marine or lake environment at the ice margin. Our ice-margin positions are made available as maps and GIS data and complement the rich record of ice-marginal landforms previously reported in the literature. Importantly, our database provides seamless, internally-consistent maps and data for use with ice sheet modelling investigations.