Estimating Ice Discharge at Greenland's Three Largest Outlet Glaciers Using Local Bedrock Uplift
peer reviewed We present a novel method to estimate dynamic ice loss of Greenland's three largest outlet glaciers: Jakobshavn Isbræ, Kangerlussuaq Glacier, and Helheim Glacier. We use Global Navigation Satellite System (GNSS) stations attached to bedrock to measure elastic displacements of the...
Published in: | Geophysical Research Letters |
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Main Authors: | , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
John Wiley and Sons Inc
2021
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Subjects: | |
Online Access: | https://orbi.uliege.be/handle/2268/301946 https://orbi.uliege.be/bitstream/2268/301946/1/Hansen_2021_GRL.pdf https://doi.org/10.1029/2021GL094252 |
Summary: | peer reviewed We present a novel method to estimate dynamic ice loss of Greenland's three largest outlet glaciers: Jakobshavn Isbræ, Kangerlussuaq Glacier, and Helheim Glacier. We use Global Navigation Satellite System (GNSS) stations attached to bedrock to measure elastic displacements of the solid Earth caused by dynamic thinning near the glacier terminus. When we compare our results with discharge, we find a time lag between glacier speedup/slowdown and onset of dynamic thinning/thickening. Our results show that dynamic thinning/thickening on Jakobshavn Isbræ occurs 0.87 ± 0.07 years before speedup/slowdown. This implies that using GNSS time series we are able to predict speedup/slowdown of Jakobshavn Isbræ by up to 10.4 months. For Kangerlussuaq Glacier the lag between thinning/thickening and speedup/slowdown is 0.37 ± 0.17 years (4.4 months). Our methodology and results could be important for studies that attempt to model and understand mechanisms controlling short-term dynamic fluctuations of outlet glaciers in Greenland. |
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