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. Naval Undersea Warfare Center Division Newportįor more information on USRD services and facilities, follow the links at right.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. It is supported by the Navy's only dedicated research and development program in underwater acoustic measurements. The USRD is part of the Sensors and Sonar Systems Department of the Naval Undersea Warfare Center Division Newport located in Newport, R.I. The USRD supports its facilities and standards with a robust research and development program dedicated to expanding the state-of-the-art in underwater acoustic measurements. It also maintains transducer standards to help ensure the accuracy of measurements made both at USRD and elsewhere. In this role the USRD maintains specialized measurement facilities with the capacity to simulate real-world ocean environments. The USRD is the Navy's primary activity for underwater acoustic calibration, test, and evaluation measurements. standardizing activity in the area of underwater acoustic measurements, as the National Institute of Standards and Technology (NIST) provides in other areas. The Underwater Sound Reference Division (USRD) serves as the U.S.
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