Reconstructing Innuitian ice sheet dynamics from subglacial drainage morphology and distribution

Glacial hydrology is one of the main controls of glacial sliding rates, on itself a key factor to estimate glacial retreat rates and sea level rise upon a warming climate. The Canadian Arctic Archipelago contains a record of extraordinarily well-preserved glaciofluvial landforms that can be traced to the margins of current polar caps, and which pose a unique opportunity to characterize and understand the shape, capacity, and dynamics of subglacial drainage. This project proposes two field campaigns in 2025 and 2026 to the Canadian Arctic Archipelago to study, characterize, and date this rare glacio-geological record left behind by Innuitian glaciation. In 2025, we propose a 3 weeks campaign to Axel Heiberg Island (80ºN, 90ºW), followed by a 2026 campaign to Devon Island (75ºN, 87ºW) to study recently exposed and minimally modified landscapes corresponding to the subglacial drainage pathways that existed under the Innuitian ice sheet and remnant Devon and Müller ice caps. Owing to the unique conditions of emplacement (thin, cold ice sheets on largely flat topography) and the reduced rainfall of the high Arctic polar desert, both islands provide unique opportunities to study the morphology, topology, density, and spatial distribution of subglacial channelized drainage patterns. Improved understanding of these features is key to comprehend the timescales of subglacial meltwater residence, the discharges related to subglacial channel activity, the competition between inefficient drainage (hence accelerated sliding) and channel emplacement, and the events that trigger the emplacement of such channels on bedrock. The implications of our work will be useful to a better understanding of the spatial characteristics of efficient subglacial drainages, which can be used in modelling efforts of ice sheets under a warming climate, but also span the study of the origin and morphology of enigmatic valleys on the surface of Mars, which could have originated under ancient ice sheets.