High basal melting forming a channel at the grounding line of Ross Ice Shelf, Antarctica

Marsh, Oliver J.; Fricker, Helen A.; Siegfried, Matthew R.; Christianson, Knut; Nicholls, Keith W, ORCID: https://orcid.org/0000-0002-2188-4509; Corr, Hugh F. J.; Catania, Ginny. 2016 High basal melting forming a channel at the grounding line of Ross Ice Shelf, Antarctica. Geophysical Research Letters, 43 (1). 250-255. 10.1002/2015GL066612

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Official URL: http://dx.doi.org/10.1002/2015GL066612

Abstract/Summary

Antarctica's ice shelves are thinning at an increasing rate, affecting their buttressing ability. Channels in the ice shelf base unevenly distribute melting, and their evolution provides insight into changing subglacial and oceanic conditions. Here we used phase-sensitive radar measurements to estimate basal melt rates in a channel beneath the currently stable Ross Ice Shelf. Melt rates of 22.2 ± 0.2 m a−1 (>2500% the overall background rate) were observed 1.7 km seaward of Mercer/Whillans Ice Stream grounding line, close to where subglacial water discharge is expected. Laser altimetry shows a corresponding, steadily deepening surface channel. Two relict channels to the north suggest recent subglacial drainage reorganization beneath Whillans Ice Stream approximately coincident with the shutdown of Kamb Ice Stream. This rapid channel formation implies that shifts in subglacial hydrology may impact ice shelf stability.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1002/2015GL066612
Programmes:	BAS Programmes > BAS Programmes 2015 > Ice Dynamics and Palaeoclimate BAS Programmes > BAS Programmes 2015 > Polar Oceans
ISSN:	00948276
Additional Keywords:	ice shelf channels, phase-sensitive radar, Whillans Ice Stream
Date made live:	23 Feb 2016 11:41 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/513057

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1002/2015GL066612

Programmes:

BAS Programmes > BAS Programmes 2015 > Ice Dynamics and Palaeoclimate
BAS Programmes > BAS Programmes 2015 > Polar Oceans

ISSN:

00948276

Additional Keywords:

ice shelf channels, phase-sensitive radar, Whillans Ice Stream

Date made live:

23 Feb 2016 11:41 +0 (UTC)