In this enlightening episode, we invite Dr. Dow, a distinguished glaciologist, to talk about a fascinating yet largely underexplored facet of Antarctica's ice sheet dynamics – its subglacial hydrological systems. The contribution of ice sheets to sea level is significantly influenced by high-pressure water lubricating the base of the ice, thereby accelerating its flow into the ocean. Yet, the processes occurring beneath Antarctica's ice have largely remained shrouded in mystery, hindering our understanding of ice-sheet flow and its response to climate change.

Dr. Dow and his team have discovered extensive, dendritically organized subglacial hydrological systems that stretch up to 460 km from the ice-sheet interior to the grounded margin using advanced numerical modeling and geophysical data. He explains how these channels transport large volumes of freshwater at high pressure, potentially augmenting the ice flow above.

The most intriguing revelation, however, is the identification of specific locations where the water exits the ice sheet, seemingly driving ice-shelf melting in these critical areas that play a pivotal role in ice-sheet stability.

Dr. Dow underscores the importance of including catchment-scale basal hydrology in calculations of ice-sheet flow and ice-shelf melt assessments at grounding zones. The findings highlight that understanding the future changes in Antarctica's marginal regions necessitates knowledge of the processes operating within and emanating from the ice-sheet interior.

Dr. Dow, Antarctica, Ice Sheets, Subglacial Hydrological Systems, Climate Change, Ice-sheet Flow, Ice-shelf Melting, Numerical Modelling, Geophysical Data, Grounding Zones.

Dow, C.F., Ross, N., Jeofry, H., et al. Antarctic basal environment shaped by high-pressure flow through a subglacial river system. Nat. Geosci. (2022). https://doi.org/10.1038/s41561-022-01059-1