Detailed Seismic Bathymetry Beneath Ekström Ice Shelf, Antarctica

Implications for Glacial History and Ice-Ocean Interaction

verfasst von

Emma C. Smith, Tore Hattermann, Gerhard Kuhn, Christoph Gaedicke, Sophie Berger, Reinhard Drews, Todd A. Ehlers, Dieter Franke, Rapahel Gromig, Coen Hofstede, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, Olaf Eisen

Abstract

The shape of ice shelf cavities are a major source of uncertainty in understanding ice-ocean interactions. This limits assessments of the response of the Antarctic ice sheets to climate change. Here we use vibroseis seismic reflection surveys to map the bathymetry beneath the Ekström Ice Shelf, Dronning Maud Land. The new bathymetry reveals an inland-sloping trough, reaching depths of 1,100 m below sea level, near the current grounding line, which we attribute to erosion by palaeo-ice streams. The trough does not cross-cut the outer parts of the continental shelf. Conductivity-temperature-depth profiles within the ice shelf cavity reveal the presence of cold water at shallower depths and tidal mixing at the ice shelf margins. It is unknown if warm water can access the trough. The new bathymetry is thought to be representative of many ice shelves in Dronning Maud Land, which together regulate the ice loss from a substantial area of East Antarctica.

Externe Organisation(en)

Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung
Norwegian Polar Institute
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR)
Eberhard Karls Universität Tübingen
Universität zu Köln
Walther-Meißner-Institut für Tieftemperaturforschung
Universität Bremen
Georg-August-Universität Göttingen

Typ

Artikel

Journal

Geophysical research letters

Band

47

ISSN

0094-8276

Publikationsdatum

28.05.2020

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Geophysik, Allgemeine Erdkunde und Planetologie

Ziele für nachhaltige Entwicklung

SDG 13 – Klimaschutzmaßnahmen, SDG 14 – Lebensraum Wasser

Elektronische Version(en)

https://doi.org/10.1029/2019GL086187 (Zugang: Offen)