Subglacial topography and ice flux along the English Coast of Palmer Land, Antarctic Peninsula

Winter, Kate, Hill, Emily, Gudmundsson, Hilmar and Woodward, John (2020) Subglacial topography and ice flux along the English Coast of Palmer Land, Antarctic Peninsula. Earth System Science Data, 12 (4). pp. 3453-3467. ISSN 1866-3516

[img]
Preview
Text
Winter_etal_2020.pdf - Published Version
Available under License Creative Commons Attribution 4.0.

Download (13MB) | Preview
Official URL: https://doi.org/10.5194/essd-12-3453-2020

Abstract

Recent satellite data have revealed widespread grounding line retreat, glacier thinning, and associated mass loss along the Bellingshausen Sea sector, leading to increased concern for the stability of this region of Antarctica. While satellites have greatly improved our understanding of surface conditions, a lack of radio-echo sounding (RES) data in this region has restricted our analysis of subglacial topography, ice thickness, and ice flux. In this paper we analyse 3000 km of 150 MHz airborne RES data collected using the PASIN2 radar system (flown at 3–5 km line spacing) to investigate the subglacial controls on ice flow near the grounding lines of Ers, Envisat, Cryosat, Grace, Sentinel, Lidke, and Landsat ice streams as well as Hall and Nikitin glaciers. We find that each outlet is topographically controlled, and when ice thickness is combined with surface velocity data from MEaSUREs (Mouginot et al., 2019a), these outlets are found to discharge over 39.25 ± 0.79 Gt a−1 of ice to floating ice shelves and the Southern Ocean. Our RES measurements reveal that outlet flows are grounded more than 300 m below sea level and that there is limited topographic support for inland grounding line re-stabilization in a future retreating scenario, with several ice stream beds dipping inland at ∼ 5∘ km−1. These data reinforce the importance of accurate bed topography to model and understand the controls on inland ice flow and grounding line position as well as overall mass balance and sea level change estimates. RES data described in this paper are available through the UK Polar Data Centre: https://doi.org/10.5285/E07D62BF-D58C-4187-A019-59BE998939CC (Corr and Robinson, 2020).

Item Type: Article
Additional Information: Funding Information: RES data were collected by the British Antarctic Survey aerogeophysical group in the austral summer of 2016/2017 and data were pre-processed by Hugh F. J. Corr (British Antarctic Survey). We acknowledge the support of Landmark Software and Services, a Landmark Company, for the use of ProMAX software. We thank all those involved in the process of planning and collecting data, as well as helpful manuscript reviews from Joseph MacGregor and the anonymous reviewer.
Subjects: F700 Ocean Sciences
F800 Physical and Terrestrial Geographical and Environmental Sciences
Department: Faculties > Engineering and Environment > Geography and Environmental Sciences
Depositing User: John Coen
Date Deposited: 17 Dec 2020 10:36
Last Modified: 31 Jul 2021 15:02
URI: http://nrl.northumbria.ac.uk/id/eprint/45027

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year

View more statistics