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

TitleHigh basal melting forming a channel at the grounding line of Ross Ice Shelf, Antarctica
Publication TypeJournal Article
Year of Publication2016
AuthorsMarsh O.J, Fricker H.A, Siegfried M.R, Christianson K., Nicholls K.W, Corr H.FJ, Catania G.
JournalGeophysical Research Letters
Volume43
Pagination250-255
Date Published2016/01
Type of ArticleArticle
ISBN Number0094-8276
Accession NumberWOS:000369014100029
Keywordsbeneath; ice shelf channels; meltwater; phase-sensitive radar; radar; rates; sheet; stream; west antarctica; Whillans Ice Stream
Abstract

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 22.20.2ma(-1) (>2500% the overall background rate) were observed 1.7km 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.

DOI10.1002/2015gl066612
Student Publication: 
No
Research Topics: 
sharknado