Low melt rates with seasonal variability at the base of Fimbul Ice Shelf, East Antarctica, revealed by in situ interferometric radar measurements

• Published in: Geophysical research letters Vol. 41; no. 22; pp. 8138 - 8146
• Main Authors: Langley, Kirsty, Kohler, Jack, Sinisalo, Anna, Øyan, Mats Jørgen, Hamran, Svein Erik, Hattermann, Tore, Matsuoka, Kenichi, Nøst, Ole Anders, Isaksson, Elisabeth
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 28-11-2014; John Wiley & Sons, Inc
• Subjects: Annual variations; Antarctica; basal melting; Buttresses; Catchment area; Continental shelves; Discharge; Estimates; Evaluation; Glaciation; Glaciers; Global warming; Ice; Ice shelves; Icebergs; Inland ice; interferometric radar; Interferometry; Land ice; Melting; Melts; Ocean models; Radar; Radar measurement; Satellite observation; Satellites; Sea level; Seasonal variability; Seasonal variations; Shelf edge; Shelves; Stability; Stability analysis; Thinning; Variability; PSE, Antarctica, Dronning Maud Land; PSE, Antarctica, East Antarctica
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2014GL061782

Basal melt is a major cause of ice shelf thinning affecting the stability of the ice shelf and reducing its buttressing effect on the inland ice. The Fimbul ice shelf (FIS) in Dronning Maud Land (DML), East Antarctica, is fed by the fast‐flowing Jutulstraumen glacier, responsible for 10% of ice discharge from the DML sector of the ice sheet. Current estimates of the basal melt rates of the FIS come from regional ocean models, autosub measurements, and satellite observations, which vary considerably. This discrepancy hampers evaluation of the stability of the Jutulstraumen catchment. Here, we present estimates of basal melt rates of the FIS using ground‐based interferometric radar. We find a low average basal melt rate on the order of 1 m/yr, with the highest rates located at the ice shelf front, which extends beyond the continental shelf break. Furthermore, our results provide evidence for a significant seasonal variability.
Key Points
Basal melt rates on the order of 1 m/yr are measured under the Fimbul ice shelfSignificant seasonal variability in the melt rates is observedSpatial pattern of basal melt is consistent with ice‐ocean and satellite studies