LINKING SURFACE MELTWATER FLUX AND ICE VELOCITIES IN SOUTHERN GREENLAND (68ºN) FROM 2016 TO 2019

Ice sheets are sensitive to surface meltwater, particularly in the summer melt season as warmer temperatures result in more melt that can access the base of the ice sheet and influence its sliding behavior. This study will attempt to understand the linkages between surface meltwater flux and ice flow velocity as they are influenced by summer speedups from May to August through 2016-2019. The 35 x 35 km study site is located on the southwestern margin (68°N) of the Greenland ice sheet and contains many supraglacial lakes. Surface meltwater storage will be investigated on a weekly basis using Sentinel-2 data by measuring the area and the optical properties of supraglacial lakes to quantify lake volume changes across the melt time period. Corresponding average weekly ice velocities will be taken from the MEaSUREs Greenland Ice Sheet Velocity Map data. Surface temperature will be estimated using ERA5-Land hourly data [1]. The resulting variations in supraglacial lake volumes, ice sheet velocity data, and averaged surface temperatures will be compared through the summer melt season (May–August). Digital elevation data will be used to assess the relationship between these variations as a function of elevation. The anticipated results will highlight the relationship between meltwater flux and ice flow velocity over the study period in response to summer speedups. A better understanding of the connections between surface temperature, surface meltwater, and ice sheet velocity are important in future projections to determine when supraglacial lakes drain and how they influence the flow of the Greenland ice sheet in a warming climate.

[1] https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-land