Articles | Volume 15, issue 12
https://doi.org/10.5194/tc-15-5409-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-15-5409-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Generation and fate of basal meltwater during winter, western Greenland Ice Sheet
Department of Geosciences, Univ. of Montana, Missoula, MT 59812, USA
Toby Meierbachtol
Department of Geosciences, Univ. of Montana, Missoula, MT 59812, USA
Neil Humphrey
Geology and Geophysics, Univ. of Wyoming, Laramie, Wyoming 82071, USA
Jun Saito
Geology and Geophysics, Univ. of Wyoming, Laramie, Wyoming 82071, USA
Aidan Stansberry
Geology and Geophysics, Univ. of Wyoming, Laramie, Wyoming 82071, USA
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We used L-band observations from the SMAP mission to quantify the surface and subsurface liquid water amounts (LWA) in the percolation zone of the Greenland ice sheet. The algorithm is described, and the validation results are provided. The results demonstrate the potential for creating an LWA data product across GrIS, which will advance our understanding of ice sheet physical processes for better projection of Greenland’s contribution to global sea level rise.
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This study presents a database compiling 95 ice temperature profiles from the Greenland ice sheet and peripheral ice caps. Ice viscosity and hence ice flow are highly sensitive to ice temperature. To highlight the value of the database in evaluating ice flow simulations, profiles from the Greenland ice sheet are compared to a modeled temperature field. Reoccurring discrepancies between modeled and observed temperatures provide insight on the difficulties faced when simulating ice temperatures.
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Short summary
We use surface and borehole measurements to investigate the generation and fate of basal meltwater in the ablation zone of western Greenland. The rate of basal meltwater generation at borehole study sites increases by up to 20 % over the winter period. Accommodation of all basal meltwater by expansion of isolated subglacial cavities is implausible. Other sinks for water do not likely balance basal meltwater generation, implying water evacuation through a connected drainage system in winter.
We use surface and borehole measurements to investigate the generation and fate of basal...