Christine Dow| Department of Geography & Environmental Management, University of Waterloo
Numerical modeling approaches for examining water flow under ice sheets
The presence of water at the bed of the Antarctic ice sheets is known to be a first order control on the speed of the overlying ice. In many regions, distribution and flux of this water is complicated by multi-year storage in subglacial lake basins. With more lakes and pockets of stored water being identified every year from satellite surface altimetry measurements and radio-echo sounding, it is apparent that constraining the impact of this water is an important step for determining the drivers of Antarctic ice dynamics.
Using a numerical modeling approach, I examine the controls on subglacial Antarctic lake growth and drainage within ice streams. I also assess whether the drainage of these lakes has an impact on the dynamics of the ice stream. The methods to achieve this utilize GlaDS, a 2-D finite element subglacial hydrology model, which incorporates development of a coexisting distributed and efficient drainage system. The model is applied both to a synthetic system and to Recovery Ice Stream in the East Antarctic with bed topography determined from mass conservation inversion techniques. The model outputs of lake growth and drainage are compared with satellite surface altimetry measurements.