nerc.ac.uk

High-resolution sub-ice-shelf seafloor records of twentieth century ungrounding and retreat of Pine Island Glacier, West Antarctica

Davies, D.; Bingham, R.G.; Graham, A.G.C.; Spagnolo, M.; Dutrieux, P.; Vaughan, D.G. ORCID: https://orcid.org/0000-0002-9065-0570; Jenkins, A. ORCID: https://orcid.org/0000-0002-9117-0616; Nitsche, F.O.. 2017 High-resolution sub-ice-shelf seafloor records of twentieth century ungrounding and retreat of Pine Island Glacier, West Antarctica. Journal of Geophysical Research: Earth Surface, 122 (9). 1698-1714. 10.1002/2017JF004311

Before downloading, please read NORA policies.
[thumbnail of Davies_et_al-2017-Journal_of_Geophysical_Research__Earth_Surface.pdf]
Preview
Text
Davies_et_al-2017-Journal_of_Geophysical_Research__Earth_Surface.pdf - Published Version
Available under License Creative Commons Attribution 4.0.

Download (2MB) | Preview

Abstract/Summary

Pine Island Glacier Ice Shelf (PIGIS) has been thinning rapidly over recent decades, resulting in a progressive drawdown of the inland ice and an upstream migration of the grounding line. The resultant ice loss from Pine Island Glacier (PIG) and its neighboring ice streams presently contributes an estimated ∼10% to global sea level rise, motivating efforts to constrain better the rate of future ice retreat. One route toward gaining a better understanding of the processes required to underpin physically based projections is provided by examining assemblages of landforms and sediment exposed over recent decades by the ongoing ungrounding of PIG. Here we present high-resolution bathymetry and sub-bottom-profiler data acquired by autonomous underwater vehicle (AUV) surveys beneath PIGIS in 2009 and 2014, respectively. We identify landforms and sediments associated with grounded ice flow, proglacial and subglacial sediment transport, overprinting of lightly grounded ice-shelf keels, and stepwise grounding line retreat. The location of a submarine ridge (Jenkins Ridge) coincides with a transition from exposed crystalline bedrock to abundant sediment cover potentially linked to a thick sedimentary basin extending upstream of the modern grounding line. The capability of acquiring high-resolution data from AUV platforms enables observations of landforms and understanding of processes on a scale that is not possible in standard offshore geophysical surveys.

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.1002/2017JF004311
ISSN: 21699003
Additional Keywords: Pine Island Glacier, West Antarctic Ice Sheet, autonomous underwater vehicle, ice sheet dynamics, bed forms, marine geophysics
Date made live: 07 Nov 2017 11:51 +0 (UTC)
URI: https://nora.nerc.ac.uk/id/eprint/518318

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...