A new bathymetry for the southeastern Filchner-Ronne Ice Shelf: implications for modern oceanographic processes and glacial history

Rosier, Sebastian, Hofstede, Coen, Brisbourne, Alex M., Hatterman, Tore, Nicholls, Keith, Davis, Peter, Anker, Paul, Hillenbrand, Claus-Dieter, Smith, Andrew and Corr, Hugh (2018) A new bathymetry for the southeastern Filchner-Ronne Ice Shelf: implications for modern oceanographic processes and glacial history. Journal of Geophysical Research: Oceans, 123 (7). pp. 14610-4623. ISSN 2169-9291

Preview	Text Rosier_et_al-2018-Journal_of_Geophysical_Research%3A_Oceans.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (2MB) | Preview
Preview	Text Rosier et al - A new bathymetry for the southeastern Filchner-Ronne Ice AAM.pdf - Accepted Version Available under License Creative Commons Attribution 4.0. Download (3MB) | Preview

Abstract

The Filchner-Ronne Ice Shelf, the ocean cavity beneath it and the Weddell Sea that bounds it, form an important part of the global climate system by modulating ice discharge from the Antarctic Ice Sheet and producing cold dense water masses that feed the global thermohaline circulation. A prerequisite for modeling the ice sheet and oceanographic processes within the cavity is an accurate knowledge of the sub-ice-sheet bedrock elevation, but beneath the ice shelf where airborne radar cannot penetrate, bathymetric data are sparse. This paper presents new seismic point measurements of cavity geometry from a particularly poorly sampled region south of Berkner Island that connects the Filchner and Ronne ice shelves. An updated bathymetric grid formed by combining the new data with existing datasets reveals several new features. In particular, a sill running between Berkner Island and the mainland could alter ocean circulation within the cavity and change our understanding of paleo-ice-stream flow in the region. Also revealed are deep troughs near the grounding lines of Foundation and Support Force ice streams, which provide access for seawater with melting potential. Running an ocean tidal model with the new bathymetry reveals large differences in tidal current velocities, both within the new gridded region and further afield, potentially affecting sub-ice-shelf melt rates.

Actions (login required)

View Item

Downloads