The percolation zone of the greenland ICE sheet (gris) is characterized by heterogeneous snow and firn structure mitigated by short duration melt events in which meltwater percolates through the…

This $155,143.95 grant was awarded by the National Aeronautics and Space Administration (NASA) to the University of Maryland, College Park to conduct research on the percolation zone of the Greenland Ice Sheet (GRIS). The research aims to leverage NASA's IceBridge radar data to update the spatial extent of the percolation zone from 2009 to the present, evaluate variability in the transitional zone between the ablation and percolation facies, and assess how changes in the percolation facies correlate with firn aquifers. The study will also employ satellite-based retrieval models to analyze spatio-temporal variability in melt magnitude and surface liquid water fraction. This grant does not have a set-aside designation. The University of Maryland, College Park is the prime contractor, and as a state-controlled institution of higher learning, it has previously received federal contract awards and grants from agencies such as the Department of Defense, Department of Transportation, and National Science Foundation to support research, education, and other academic activities.

The percolation zone of the greenland ICE sheet (gris) is characterized by heterogeneous snow and firn structure mitigated by short duration melt events in which meltwater percolates through the snowpack and mostly refreezes. The gris has experienced significant and wide spread warming over the last couple decades resulting in increasing occurrence and intensity of surface melting over the percolation zone even though this facies has remained spatially stable below 2000 m during the 20TH century. Melt enhancements within this facies could facilitate near subsurface conditions suitable for the encroachment of more developed supraglacial hydrologic systems (i.e. lakes, streams). Given this, we seek to leverage NASA operational icebridge radar to update the spatial extent of the percolation zone from 2009 to present. Over this period we will evaluate spatial variability in conditions in the transitional zone between the ablation and percolation facies which includes examination of ICE sheet-wide changes in the occurrence and distribution of supraglacial lakes and streams. We will also employ a novel satellite-based retrieval model based on a data fusion of passive microwave and coupled optical/thermal measurements to assess the spatio-temporal variability in melt magnitude or surface liquid water fraction. Lastly, we seek to assess how changes in the percolation facies correlate with previously detected firn aquifers and diagnose how contemporary seasonal variability in surface mass balance conditions allow for the development and proliferation of aquifer systems.