Modelling seasonal meltwater forcing of the velocity of land-terminating margins of the Greenland Ice Sheet ...

• Main Authors: Koziol, Conrad P, Arnold, Neil
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2018
• Subjects: 3707 Hydrology; 3709 Physical Geography and Environmental Geoscience; 37 Earth Sciences; 3705 Geology; 13 Climate Action; Greenland; Ice Sheet
• Online Access: https://dx.doi.org/10.17863/cam.32770; https://www.repository.cam.ac.uk/handle/1810/285407

Surface runoff at the margin of the Greenland Ice Sheet (GrIS) drains to the ice-sheet bed, leading to enhanced summer ice flow. Ice velocities show a pattern of early summer acceleration followed by mid-summer deceleration due to evolution of the subglacial hydrology system in response to meltwater forcing. Modelling the integrated hydrological–ice dynamics system to reproduce measured velocities at the ice margin remains a key challenge for validating the present understanding of the system and constraining the impact of increasing surface runoff rates on dynamic ice mass loss from the GrIS. Here we show that a multi-component model incorporating supraglacial, subglacial, and ice dynamic components applied to a land-terminating catchment in western Greenland produces modelled velocities which are in reasonable agreement with those observed in GPS records for three melt seasons of varying melt intensities. This provides numerical support for the hypothesis that the subglacial system develops analogously to ...