Atlantic water intrusion triggers rapid retreat and regime change at previously stable Greenland glacier

Chudley, T.R.; Howat, I.M.; King, M.D.; Negrete, A.

Abstract

Ice discharge from Greenland’s marine-terminating glaciers contributes to half of all mass loss from the ice sheet, with numerous mechanisms proposed to explain their retreat. Here, we examine K.I.V Steenstrups Nordre Bræ (‘Steenstrup’) in Southeast Greenland, which, between 2018 and 2021, retreated ~7 km, thinned ~20%, doubled in discharge, and accelerated ~300%. This rate of change is unprecedented amongst Greenland’s glaciers and now places Steenstrup in the top 10% of glaciers by contribution to ice-sheet-wide discharge. In contrast to expected behaviour from a shallow, grounded tidewater glacier, Steenstrup was insensitive to high surface temperatures that destabilised many regional glaciers in 2016, appearing instead to respond to a >2 °C anomaly in deeper Atlantic water (AW) in 2018. By 2021, a rigid proglacial mélange had developed alongside notable seasonal variability. Steenstrup’s behaviour highlights that even long-term stable glaciers with high sills are vulnerable to sudden and rapid retreat from warm AW intrusion.

Citation

Chudley, T., Howat, I., King, M., & Negrete, A. (2023). Atlantic water intrusion triggers rapid retreat and regime change at previously stable Greenland glacier. Nature Communications, 14(1), Article 2151. https://doi.org/10.1038/s41467-023-37764-7

• Journal Article Type: Article
• Acceptance Date: Mar 30, 2023
• Online Publication Date: Apr 19, 2023
• Publication Date: 2023
• Deposit Date: Apr 26, 2023
• Publicly Available Date: Aug 18, 2023
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 14
• Issue: 1
• Article Number: 2151
• DOI: https://doi.org/10.1038/s41467-023-37764-7
• Public URL: https://durham-repository.worktribe.com/output/1175259