Seasonal Lakes: Modeling Meltwater on the Greenland Ice Sheet

Schimmel/Conrades Science Center Atrium

Enhanced glacial melt has been observed across the Greenland Ice Sheet (GrIS), including the Ilullisat Glacier (commonly known as Jakobshavn Isbrae) over the past few decades. This increased glacier meltwater channelizes across the surface to form supraglacial melt lakes in topographic depressions. Surface melt across the ablation zone (or melt zone) of the GrIS is driven by near-surface air temperature above the melting point (0 C). We have identified a supraglacial lake in the catchment area that forms regularly over subsequent melt seasons, and is in close proximity to a Greenland Climate Network (GC-Net) automated weather station (AWS). The catchment area for this lake is defined by a high-resolution digital elevation model (DEM). We apply the Positive Degree Day (PDD) model to the catchment area to model the production of surface meltwater in the basin over the period of melt lake growth. The modeled results are then compared to the changes in supraglacial melt lake size from acquired Landsat-8 imagery over the period.