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### Access Dataset and extensive metadata can be accessed and downloaded via: [https://arcticdata.io/data/10.18739/A2CZ32678/](https://arcticdata.io/data/10.18739/A2CZ32678/) ### Overview A limited understanding of how glacier-ocean interactions lead to iceberg calving and melting at the ice-ocean boundary contributes to uncertainty in predictions of sea level rise. Dense packs of icebergs and sea ice, known as ice mélange, occur in many fjords in Greenland and Antarctica. Observations suggest that ice mélange may directly affect iceberg calving by pressing against the glacier front and indirectly affect glacier melting by controlling where and when icebergs melt which can impact ocean circulation and ocean heat transport towards glaciers. However, the interactions between ice mélange, ocean circulation, and iceberg calving have not been systematically investigated due to the difficulty of conducting field work in Greenland fjords. In order to investigate the dynamics of ice mélange (and other floating granular materials) and to inform development of ice mélange models, we conducted a series of laboratory experiments using synthetic icebergs (plastic blocks) that were pushed down a tank by a synthetic glacier. This data set consists of force measurements on the glacier terminus and time-lapse photographs of the experiments that were used for visualizing motion.
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Quantifying iceberg calving fluxes with underwater noise
Abstract. Accurate estimates of calving fluxes are essential inunderstanding small-scale glacier dynamics and quantifying the contribution ofmarine-terminating glaciers to both eustatic sea-level rise (SLR) and thefreshwater budget of polar regions. Here we investigate the application ofacoustical oceanography to measure calving flux using the underwater soundsof iceberg–water impact. A combination of time-lapse photography and passiveacoustics is used to determine the relationship between the mass and impactnoise of 169 icebergs generated by subaerial calving events from Hansbreen,Svalbard. The analysis includes three major factors affecting the observednoise: (1) time dependency of the thermohaline structure, (2) variability inthe ocean depth along the waveguide and (3) reflection of impact noise fromthe glacier terminus. A correlation of 0.76 is found between the(log-transformed) kinetic energy of the falling iceberg and thecorresponding measured acoustic energy corrected for these three factors. Anerror-in-variables linear regression is applied to estimate the coefficientsof this relationship. Energy conversion coefficients for non-transformedvariables are 8×10-7 and 0.92, respectively, for themultiplication factor and exponent of the power law. This simple model canbe used to measure solid ice discharge from Hansbreen. Uncertainty in theestimate is a function of the number of calving events observed; 50 %uncertainty is expected for eight blocks dropping to 20 % and 10 %,respectively, for 40 and 135 calving events. It may be possible to lowerthese errors if the influence of different calving styles on the receivednoise spectra can be determined.
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- Award ID(s):
- 1748265
- PAR ID:
- 10250305
- Date Published:
- Journal Name:
- The Cryosphere
- Volume:
- 14
- Issue:
- 3
- ISSN:
- 1994-0424
- Page Range / eLocation ID:
- 1025 to 1042
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/tc-14-1025-2020
