Analysis of Sub-Antarctic Lakes Using a Coupled Hydrology and Ice Flexure Modeling Approach

Abstract:

The role of sub-Antarctic lakes in subglacial hydrological development and ice dynamics is not well constrained. We present a novel coupled modeling approach for assessing the stability of subglacial lakes in the Antarctic, the controls on their growth and demise, and the downstream impact of leakage of water from these substantial water reservoirs. Our method utilizes GlaDS, a 2-D finite element hydrology model, with the capability for development of a coexisting distributed and efficient drainage system. To better constrain lake growth and drainage, along with the dynamic impact of the water reservoir, we locally couple the hydrology model to an ice flexure model. We are interested in constraining the change in local ice stresses due to the growth of lakes and assessing the triggers of rapid or slow lake drainage. These lake dynamic analyses contribute to our assessment of the role of lakes in basal hydrology, with a focus on ice streams, where we examine whether the drainage mechanisms have an impact on regional ice dynamics. Here we present our method and initial results from the coupled model.