Surface melt from RACMOv2.3. --- Date created: December 2014 Public Deposited
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.
Output from RACMO regional climate model, version 2.3, for the total melt (ice melt plus snow melt) on the ice-sheet surface within the study area in western Greenland. Data are averaged into elevation bands, e.g., 0-200 meters elevation, which are given in the first two columns for each row. The data are also averaged in time to one year resolution (1958-2013); these data appear in the following columns. Surface melt is given in mm/yr, water equivalent.