Antarctic subglacial groundwater: a concept paper on its measurement and potential influence on ice flow ...

• Main Authors: Siegert, MJ, Kulessa, B, Bougamont, MH, Christoffersen, P, Key, K, Andersen, KR, Booth, AD, Smith, AM
• Format: Article in Journal/Newspaper
• Language: English
• Published: Geological Society 2018
• Subjects: 3707 Hydrology; 3709 Physical Geography and Environmental Geoscience; 37 Earth Sciences; 3705 Geology; 13 Climate Action; Antarctic; Antarc*; Antarctica; Ice Sheet
• Online Access: https://dx.doi.org/10.17863/cam.8570; https://www.repository.cam.ac.uk/handle/1810/263250

Is groundwater abundant in Antarctica and does it modulate ice flow? Answering this question matters because ice streams flow by gliding over a wet substrate of till. Water fed to ice-stream beds thus influences ice-sheet dynamics and, potentially, sea-level rise. It is recognised that both till and the sedimentary basins from which it originates are porous and could host a reservoir of mobile groundwater that interacts with the subglacial interfacial system. According to recent numerical modelling up to half of all water available for basal lubrication, and time lags between hydrological forcing and ice-sheet response as long as millennia, may have been overlooked in models of ice flow. Here, we review evidence in support of Antarctic groundwater and propose how it can be measured to ascertain the extent to which it modulates ice flow. We present new seismoelectric soundings of subglacial till, and magnetotelluric and transient electromagnetic forward models of subglacial groundwater reservoirs. We ...