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

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

Research output: Contribution to journalArticlepeer-review

2 Downloads (Pure)

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.
Original languageEnglish
Article number7840
JournalNature Communications
Volume13
DOIs
Publication statusPublished - 21 Dec 2022

Cite this