Mass flux from Kangerlussuaq Glacier, East Greenland, modeled in a 200-year perspective

Understanding the dynamics of the large outlet glaciers draining the Greenland Ice Sheet continues to be of great importance. In certain areas, recent estimates of the partition of mass loss between surface mass balance (SMB) and dynamic effects (thinning, increased calving flux) have shifted towards a much larger dynamic fraction than previously believed (Khan et al., EPSL, 2011, under rev.), requiring this budget to be re-evaulated at the large outlets. While the cause of this change is not well understood, much insight into the response of the large outlet glaciers to climate forcings can be gained from relatively simple 1D flowline models. Here, we use a suite of recent radar and airborne laser altimetry data to establish an initial geometry of Kangerlussuaq Glacier, East Greenland. We then model the calving flux and changing geometry in a 200-year perspective, forced by predictive climate models in a number of scenarios. In the glacier model, we account for spatially and temporally varying melt-water induced accelerations (Andersen et al., 2010; 2011), as well as subsurface melt at the terminus. We also include changes in back pressure from variations in ice-melange volume over the season.