Estimating ice discharge at Greenland's three largest outlet glaciers using local bedrock uplift

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 ca...

Full description

Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Hansen, Karina, Truffer, Martin, Aschwanden, Andy, Mankoff, Kenneth, Bevis, Michael, Humbert, Angelika, Broeke, Michiel R., Noël, Brice, Bjørk, Anders, Colgan, William, Kjær, Kurt H, Adhikari, Surendra, Barletta, Valentina, Khan, Shfaqat A.
Format: Article in Journal/Newspaper
Language:English
Published: 2021
Subjects:
Greenland
Jakobshavn Isbræ
Kangerlussuaq
glacier
Jakobshavn
Jakobshavn isbræ
Online Access:https://orbit.dtu.dk/en/publications/ae0b6c7b-f4cc-4536-99d2-1968d58ee10a
https://doi.org/10.1029/2021GL094252
https://backend.orbit.dtu.dk/ws/files/259139508/2021GL094252_1_.pdf
Description
Summary: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.

Similar Items