Calving-driven fjord dynamics resolved by seafloor fibre sensing

Area of Science:

• Glaciology
• Oceanography
• Climate Science

Background:

• Warming oceans and melting ice drive Greenland's tidewater glacier retreat.
• Ice-ocean interactions, including calving and submarine melt, are critical for glacier ablation but poorly understood.
• Observing these processes near calving fronts is challenging due to hazardous conditions.

Purpose of the Study:

• To investigate the link between iceberg calving and submarine melt.
• To understand the role of calving in glacier-ocean interactions and frontal ablation.
• To provide new insights into the dynamics of retreating tidewater glaciers.

Main Methods:

• Utilized front-proximal submarine fiber sensing.
• Observed the iceberg calving process chain, from fracturing to iceberg decay.
• Measured associated phenomena like internal waves and currents.

Main Results:

• Iceberg calving acts as a submarine melt amplifier by exciting internal waves.
• Calving initiates ice fracturing, detachment, and generates local tsunamis and currents.
• Previously unknown pathways of tidewater glacier-ocean interaction were identified.

Conclusions:

• Calving-induced internal waves enhance submarine melt at glacier fronts.
• These findings help explain glacier frontal ablation, improving climate models.
• Provides crucial process-scale understanding for global tidewater glacier retreat.