Modeled basal temperate area in western Greenland using Fox Maule et al. (2005) geothermal flux. Public Deposited
Results of the thermal model runs in western Greenland using geothermal flux from Fox Maule et al. (2005) as a boundary condition. The (x,y) points in this file outline the wet-bedded region: the model predicts that points inside the polygon have a wet (temperate) bed.
Description of this collection of datasets: Moulins are important conduits for surface meltwater to reach the bed of the Greenland Ice Sheet. It has been proposed that in a warming climate, newly formed moulins associated with the inland migration of supraglacial lakes could introduce surface melt to new regions of the bed, introducing or enhancing sliding there. By examining surface strain rates, we found that the upper limit to where crevasses, and therefore moulins, are likely to form is ~1600 m. This is also roughly the elevation above which lakes do not drain completely. Thus, meltwater above this elevation will largely flow tens of kilometers through surface streams into existing moulins downstream. Furthermore, results from a thermal ice-sheet model indicate that the ~1600-m crevassing limit is below the wet–frozen basal transition (~2000 m). Together, these datasets suggest that new supraglacial lakes will have a limited effect on the inland expansion of melt-induced seasonal acceleration.