Modelling Subglacial Hydrology under Future Climate Scenarios in Wilkes Subglacial Basin, Antarctica
- 1Department of Applied Mathematics, University of Waterloo, Waterloo, ON, Canada
- 2Department of Geography and Environmental Management, University of Waterloo, Waterloo, ON, Canada
- 3Department of Earth Sciences, Dartmouth College, Hanover, NH, USA
- 4School of Earth, Atmosphere and Environment, Monash University, Melbourne, VIC, Australia
- 5Department of Earth Sciences, Simon Fraser University, Burnaby, BC, Canada
The Greenland and Antarctic ice sheets have differing climates, which makes surface melt a significant hydrological source in Greenland but not currently in Antarctica. Due to changing climate and warming air temperatures, Antarctica is predicted to experience more surface meltwater in the future. This will likely lead to surface features common in Greenland today, such as supraglacial lakes and moulins, to also form over grounded ice in Antarctica. Moulins in particular are important because they will route this surface melt into basal drainage networks. The resulting change in subglacial drainage characteristics and water volumes will potentially have far-reaching impacts on ice dynamics, ice shelf melt, grounding line stability, and ultimately global sea level rise. To examine this, we model the hydrological system in Wilkes Subglacial Basin, East Antarctica with the future climate in mind by incorporating moulins and surface melt to try to understand the impact that this will have on ice sheet and ice shelf dynamics. We use predictive data generated by the Community Climate System Model 4 (CCSM4) for surface runoff in Antarctica for the year 2100 as inputs to the Glacier Drainage System (GlaDS) subglacial hydrology model. We compare the modelling results from two different Representative Concentration Pathway (RCP) scenarios, RCP 2.6 and RCP 8.5. Moulin locations are predicted using current strain rates along preferential surface hydrology flow pathways and we also compare modelling results with different numbers and locations of moulins. Preliminary results show that even under the lower RCP 2.6 scenario, surface water input significantly alters basal drainage rates, channel extent, and water pressure near the grounding line. The changes are focussed during the modelled summer melt season with the hydrological system settling towards its current state over winter. This demonstrates that the future state of the climate will have an impact on the subglacial hydrology of Antarctica and, in turn, on ice flow speeds and ice shelf melt rates near the grounding line.
How to cite: Siu, K., Dow, C., Morlighem, M., McCormack, F., and Hill, T.: Modelling Subglacial Hydrology under Future Climate Scenarios in Wilkes Subglacial Basin, Antarctica, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-424, https://doi.org/10.5194/egusphere-egu22-424, 2022.
