Near-margin ice thickness and subglacial water routing, Leverett Glacier, Greenland

Subglacial hydrology and ice stream margin locations

Fast flowing ice streams in West Antarctica are separated from the nearly stagnant ice in the adjacent ridge by zones of highly localized deformation known as shear margins. It is presently uncertain what mechanisms control the location of shear margins, and possibly allow them to migrate. In this paper we show how subglacial hydrological processes can select the shear margin location, leading ...

Greenland outlet glacier ice - flow variability

1 I ce mass loss from the Greenland Ice Sheet is a primary contributor to global sea level rise. The rate of ice loss has accelerated over the last couple of decades and Greenland currently contributes about 0.7-1.1 mm/yr to sea-level rise (260-380 Gt/ice per year; Enderlin et al. 2014; Shepherd et al. 2012). Predicting the potential rate and limits of future mass loss requires a clear understa...

Subglacial lake drainage detected beneath the Greenland ice sheet

The contribution of the Greenland ice sheet to sea-level rise has accelerated in recent decades. Subglacial lake drainage events can induce an ice sheet dynamic response--a process that has been observed in Antarctica, but not yet in Greenland, where the presence of subglacial lakes has only recently been discovered. Here we investigate the water flow paths from a subglacial lake, which drained...

Modelling the transfer of supraglacial meltwater to the bed of Leverett Glacier, Southwest Greenland

Meltwater delivered to the bed of the Greenland Ice Sheet is a driver of variable ice-motion through changes in effective pressure and enhanced basal lubrication. Ice surface velocities have been shown to respond rapidly both to meltwater production at the surface and to drainage of supraglacial lakes, suggesting efficient transfer of meltwater from the supraglacial to subglacial hydrological s...

Ice flux divergence anomalies on 79north Glacier, Greenland