Ocean variability beneath Thwaites Eastern Ice Shelf driven by the Pine Island Bay Gyre strength

Tiago S Dotto; Karen J Heywood; Rob A Hall; Ted A Scambos; Yixi Zheng; Yoshihiro Nakayama; Shuntaro Hyogo; Tasha Snow; Anna K Wåhlin; Christian Wild; Martin Truffer; Atsuhiro Muto; Karen E Alley; Lars Boehme; Guilherme A Bortolotto; Scott W Tyler; Erin Pettit

doi:10.1038/s41467-022-35499-5

Ocean variability beneath Thwaites Eastern Ice Shelf driven by the Pine Island Bay Gyre strength

Nat Commun. 2022 Dec 21;13(1):7840. doi: 10.1038/s41467-022-35499-5.

Authors

Tiago S Dotto¹, Karen J Heywood², Rob A Hall², Ted A Scambos³, Yixi Zheng², Yoshihiro Nakayama⁴, Shuntaro Hyogo⁵, Tasha Snow⁶, Anna K Wåhlin⁷, Christian Wild⁸, Martin Truffer⁹, Atsuhiro Muto¹⁰, Karen E Alley¹¹, Lars Boehme¹², Guilherme A Bortolotto¹², Scott W Tyler¹³, Erin Pettit⁸

Affiliations

¹ Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, UK. t.segabinazzi-dotto@uea.ac.uk.
² Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, UK.
³ Earth Science and Observation Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA.
⁴ Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan.
⁵ Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan.
⁶ Department of Geophysics, Colorado School of Mines, Golden, CO, USA.
⁷ Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden.
⁸ College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA.
⁹ Geophysical Institute and Department of Physics, University of Alaska Fairbanks, Fairbanks, AL, USA.
¹⁰ Department of Earth and Environmental Science, Temple University, Philadelphia, PA, USA.
¹¹ Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada.
¹² Scottish Oceans Institute, University of St Andrews, St Andrews, UK.
¹³ Department of Geological Sciences and Engineering, University of Nevada, Reno, NV, USA.

Abstract

West Antarctic ice-shelf thinning is primarily caused by ocean-driven basal melting. Here we assess ocean variability below Thwaites Eastern Ice Shelf (TEIS) and reveal the importance of local ocean circulation and sea-ice. Measurements obtained from two sub-ice-shelf moorings, spanning January 2020 to March 2021, show warming of the ice-shelf cavity and an increase in meltwater fraction of the upper sub-ice layer. Combined with ocean modelling results, our observations suggest that meltwater from Pine Island Ice Shelf feeds into the TEIS cavity, adding to horizontal heat transport there. We propose that a weakening of the Pine Island Bay gyre caused by prolonged sea-ice cover from April 2020 to March 2021 allowed meltwater-enriched waters to enter the TEIS cavity, which increased the temperature of the upper layer. Our study highlights the sensitivity of ocean circulation beneath ice shelves to local atmosphere-sea-ice-ocean forcing in neighbouring open oceans.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antarctic Regions
Atmosphere*
Bays*
Caspase 1
Hot Temperature
Ice Cover
Oceans and Seas
Temperature

Substances

Caspase 1