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Abstract Calving icebergs at tidewater glaciers release large amounts of potential energy. This energy—in principle—could be a source for submarine melting, which scales with near‐terminus water temperature and velocity. Because near‐terminus currents are challenging to observe or predict, submarine melt remains a key uncertainty in projecting tidewater glacier retreat and sea level rise. Here, we study one submarine calving event at Xeitl Sít’ (LeConte Glacier), Alaska, to explore the effect of calving on ice melt, using a suite of autonomously deployed instruments beneath, around, and downstream of the calving iceberg. Our measurements captured flows exceeding 5 m/s and demonstrate how potential energy converts to kinetic energy . While most energy decays quickly (through turbulence, mixing, and radiated waves), near‐terminus remains elevated, nearly doubling predicted melt rates for hours after the event. Calving‐induced currents could thus be an important overlooked energy source for submarine melt and glacier retreat.
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This content will become publicly available on August 14, 2026
Calving-driven fjord dynamics resolved by seafloor fibre sensing
Abstract Interactions between melting ice and a warming ocean drive the present-day retreat of tidewater glaciers of Greenland1–3, with consequences for both sea level rise4and the global climate system5. Controlling glacier frontal ablation, these ice–ocean interactions involve chains of small-scale processes that link glacier calving—the detachment of icebergs6—and submarine melt to the broader fjord dynamics7,8. However, understanding these processes remains limited, in large part due to the challenge of making targeted observations in hazardous environments near calving fronts with sufficient temporal and spatial resolution9. Here we show that iceberg calving can act as a submarine melt amplifier through excitation of transient internal waves. Our observations are based on front-proximal submarine fibre sensing of the iceberg calving process chain. In this chain, calving initiates with persistent ice fracturing that coalesces into iceberg detachment, which in turn excites local tsunamis, internal gravity waves and transient currents at the ice front before the icebergs eventually decay into fragments. Our observations show previously unknown pathways in which tidewater glaciers interact with a warming ocean and help close the ice front ablation budget, which current models struggle to do10. These insights provide new process-scale understanding pertinent to retreating tidewater glaciers around the globe.
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- PAR ID:
- 10674464
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature
- Volume:
- 644
- Issue:
- 8076
- ISSN:
- 0028-0836
- Page Range / eLocation ID:
- 404 to 412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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