Calving from tidewater glaciers is a consequence of stress induced by different mechanisms, including (1) longitudinal stretching, (2) melt undercutting at or below the sea surface, (3) changes in terminus height and position (bay and glacier geometry) and (4) buoyancy forces (van der Veen, Reference van der Veen2002 Benn and others, Reference Benn, Warren and Mottram2007). Iceberg calving, defined as the mechanical loss of ice from ice shelves and glaciers (Benn and others, Reference Benn, Warren and Mottram2007), is a key process in glacial retreat. Vieli and Nick, Reference Vieli and Nick2011 Straneo and others, Reference Straneo2013). However, our understanding of ice–ocean interactions is largely limited by two factors: (1) difficulty in acquiring observational data in remote glacierized regions and (2) poor representation of key physical processes in numerical models (e.g. The ice loss from ice sheets is largely focused around ocean margins (Pritchard and others, Reference Pritchard, Arthern, Vaughan and Edwards2009 Rignot and others, Reference Rignot2019) and results from increased surface melting and runoff (Hanna and others, Reference Hanna2011), as well as the thinning, acceleration and retreat of tidewater (or marine-terminating) glaciers and ice shelves (King and others, Reference King2020). The Greenland and Antarctic ice sheets are also expected to lose mass under all climate scenarios (Pattyn and others, Reference Pattyn2018 Aschwanden and others, Reference Aschwanden2019 Bamber and others, Reference Bamber, Oppenheimer, Kopp, Aspinall and Cooke2019 Holland and others, Reference Holland, Nicholls and Basinski2020). Glaciers in some mountain ranges could almost disappear in this century as a result of current deglaciation (Zemp and others, Reference Zemp2019 Marzeion and others, Reference Marzeion2020). Ice loss from glaciers and ice sheets accounted for more than 50% of the global-mean sea-level rise over 1993–2018 (Frederikse and others, Reference Frederikse2020). Human-induced increases in greenhouse gases during the industrial era and resulting global warming have led to the accelerated retreat of land-based ice (Roe and others, Reference Roe, Christian and Marzeion2021). The latter will also require knowledge of the relationship between ice mass and sound spectral level for submarine calving events. The newly developed classification model may potentially be used for two purposes: (1) to study potential causal relationships between these two calving modes and (2) to separate calving fluxes into subaerial and submarine components. However, submarine events can be distinguished from subaerial events by using the shape parameter of the log-normal distribution paired with the calving signal duration. Statistical analysis of the acoustic signal shows that the normalized power of the calving noise is log-normally distributed regardless of the calving mode. This study investigates the underwater noise from 656 subaerial and 162 submarine calving events observed at Hansbreen, Svalbard in the summers of 20. However, little is known about the acoustic signatures of submarine calving. Recent results have demonstrated the effective application of passive cryoacoustics – the use of naturally generated sounds to study the cryosphere – to quantify subaerial calving fluxes. Iceberg calving is one of the major mechanisms of ice loss from tidewater glaciers and ice sheets, but obtaining accurate estimates of ice discharge that are both continuous and accurate is a challenging task.
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