Review
Astronomy & Astrophysics
R. B. Alley, K. M. Cuffey, J. N. Bassis, K. E. Alley, S. Wang, B. R. Parizek, S. Anandakrishnan, K. Christianson, R. M. DeConto
Summary: Uncertainty about sea-level rise is mainly caused by uncertainty about iceberg calving and mass loss from fracturing. There are five persistent and predictable regimes of calving that are controlled primarily by ice flow, and small perturbations do not have significant effects. However, large perturbations may lead to rapid transitions between regimes or between calving and non-calving behavior. These regime transitions are the major uncertainties in sea-level rise projections but have not been observed instrumentally. Process-based models and assimilation of paleoclimatic data could help reduce uncertainties about regime transitions. Neglecting accurate calving in predictive models could result in significant underestimation of warming-induced sea-level rise.
ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES
(2023)
Article
Multidisciplinary Sciences
Alex Huth, Alistair Adcroft, Olga Sergienko, Nuzhat Khan
Summary: The research shows that the breakup of giant iceberg A68a may have been triggered by ocean-current shear, a new breakup mechanism. Current climate models do not adequately represent giant icebergs, and the introduction of new methods will help improve the accuracy of global climate simulations.
Article
Multidisciplinary Sciences
E. Larour, E. Rignot, M. Poinelli, B. Scheuchl
Summary: Research has shown that ice shelf thinning does not reactivate rifts, but rather heals them; on the other hand, thinning of the ice melange encasing preexisting rifts controls the opening rate of the rift, with an above-linear dependence on thinning.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Geosciences, Multidisciplinary
Max Thomas, Jeff K. Ridley, Inga J. Smith, David P. Stevens, Paul R. Holland, Shona Mackie
Summary: In this research, a coupled climate model is used to investigate the feedbacks between subsurface continental shelf ocean temperatures and Antarctic glacial melt. The model is forced with SSP5-8.5 and an uncoupled projection of basal melt and calving fluxes. The results show that additional glacial melt at depth cools certain seas, suggesting a negative feedback on basal melt. However, in other regions, additional glacial melt increases temperatures at the continental shelf sea floor, suggesting a positive feedback.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Mengzhen Qi, Yan Liu, Jiping Liu, Xiao Cheng, Yijing Lin, Qiyang Feng, Qiang Shen, Zhitong Yu
Summary: Iceberg calving is a significant process contributing to the mass loss of ice sheets, with approximately half of the mass loss of the Antarctic ice sheet attributed to this mechanism. Observations of iceberg calving variability provide insights into calving mechanisms and the effects of changing climate on global sea level through the ice shelf buttressing effect. The dataset developed in this study records 1975 annual calving events larger than 1 km(2) on Antarctic ice shelves from 2005 to 2020, offering detailed information on each event for studying spatial-temporal variations in Antarctic iceberg calving.
EARTH SYSTEM SCIENCE DATA
(2021)
Review
Environmental Studies
Jeroen Ingels, Richard B. Aronson, Craig R. Smith, Amy Baco, Holly M. Bik, James A. Blake, Angelika Brandt, Mattias Cape, David Demaster, Emily Dolan, Eugene Domack, Spencer Fire, Heidi Geisz, Michael Gigliotti, Huw Griffiths, Kenneth M. Halanych, Charlotte Havermans, Falk Huettmann, Scott Ishman, Sven A. Kranz, Amy Leventer, Andrew R. Mahon, James McClintock, Michael L. McCormick, B. Greg Mitchell, Alison E. Murray, Lloyd Peck, Alex Rogers, Barbara Shoplock, Kathryn E. Smith, Brittan Steffel, Michael R. Stukel, Andrew K. Sweetman, Michelle Taylor, Andrew R. Thurber, Martin Truffer, Anton van de Putte, Ann Vanreusel, Maria Angelica Zamora-Duran
Summary: The calving of icebergs from Antarctic ice shelves is a significant indicator of rapid warming and has global-scale implications on Southern Ocean ecosystems and continental ice movements.
WILEY INTERDISCIPLINARY REVIEWS-CLIMATE CHANGE
(2021)
Article
Environmental Sciences
Joshuah Wolper, Ming Gao, Martin P. Luthi, Valentin Heller, Andreas Vieli, Chenfanfu Jiang, Johan Gaume
Summary: The study reproduces dynamic glacier fracture and iceberg-induced tsunamis using a numerical model, validated with observations at Eqip Sermia glacier in Greenland. By modeling glacier fracture and tsunami wave propagation, it helps improve modeling of solid-fluid interactions in large-scale earth-system models and enhances hazard assessments and mitigation measures in coastal regions.
COMMUNICATIONS EARTH & ENVIRONMENT
(2021)
Article
Geography, Physical
Mauro M. Barbat, Thomas Rackow, Christine Wesche, Hartmut H. Hellmer, Mauricio M. Mata
Summary: Drifting icebergs pose significant hazards for polar navigation and impact the ocean environment. A novel automated iceberg tracking method based on machine learning was proposed in this study, demonstrating the ability to detect and track icebergs in the challenging Antarctic environment. The method revealed prevalent drift patterns, size variability, average disintegration rates, and estimated a total iceberg mass decrease.
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING
(2021)
Article
Geography, Physical
YoungHyun Koo, Hongjie Xie, Stephen F. Ackley, Alberto M. Mestas-Nunez, Grant J. Macdonald, Chang-Uk Hyun
Summary: This study utilizes Sentinel-1 SAR images and the GEE platform to track the drift of iceberg B43 in the Southern Ocean, successfully detecting its drift trajectory and observing changes in iceberg characteristics.
Article
Oceanography
A. T. Bradley, D. T. Bett, P. Dutrieux, J. De Rydt, P. R. Holland
Summary: The combination of the Pine Island Ice Shelf draft and a seabed ridge beneath it form a topographic barrier, which controls the access of warm water and plays a key role in the basal ablation of the ice shelf. The recent large calving events of the ice shelf could significantly change the cavity geometry and melt rates. Results from high-resolution ocean model simulations suggest that while the melt rates did not respond significantly to recent calving, further calving could increase the melt rates linearly by approximately 10%, providing evidence for the importance of calving in the ice-ocean sensitivity of the West Antarctic Ice Sheet.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geosciences, Multidisciplinary
Kristin M. Schild, David A. Sutherland, Pedro Elosegui, Daniel Duncan
Summary: The study presents a novel in situ method using high-precision GPS units to capture iceberg melt rates at a high temporal and spatial resolution. The calculated melt rates are lower than previous studies, likely due to using individual subsurface iceberg geometries in calculations. By combining these new measurements with remote sensing data, a better prediction of the impact of increasing freshwater input from the Greenland Ice Sheet can be made.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Oceanography
Juliana M. Marson, Laura C. Gillard, Paul G. Myers
Summary: While the impact of Greenland discharge on the Meridional Overturning Circulation (MOC) has not been clearly established, sensitivity experiments show that different parameterizations of Greenland solid discharge can have significant impacts on the western subpolar Atlantic. Icebergs act as freshwater reservoirs, affecting the delivery of freshwater to the ocean, and the amount and variability of freshwater depend not only on Greenland discharge characteristics but also on the environmental conditions icebergs experience. Differences in ocean fields between simulations may be relevant as Greenland calving rates increase with global warming.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Remote Sensing
Yuan Cheng, Menglian Xia, Gang Qiao, Yanjun Li, Gang Hai, Da Lv
Summary: This study investigates iceberg calving events of the Ninnis Glacier in Antarctica utilizing satellite imagery and field measurements, revealing changes in calving area and breaking locations, potentially related to local oceanographic conditions.
INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION
(2021)
Article
Environmental Sciences
Zhaohui Chi, Andrew Klein
Summary: Research has shown a massive iceberg broke off the west side of the Amery Ice Shelf in East Antarctica in 2019. Mapping eight calving front locations of the AIS from 1973 to 2018 revealed an increased advancement rate, while the unstable propagation of rift A from 2012 to 2015 and the significantly faster propagation rate of rift A1 from 2015 to 2017 may have been precursors to the large calving event.
Article
Geosciences, Multidisciplinary
Yoshihiro Nakayama, Chad A. Greene, Fernando S. Paolo, Vigan Mensah, Hong Zhang, Haruhiko Kashiwase, Daisuke Simizu, Jamin S. Greenbaum, Donald D. Blankenship, Ayako Abe-Ouchi, Shigeru Aoki
Summary: Research suggests that the Antarctic Slope Current (ASC) plays a blocking role in intrusions of warm modified Circumpolar Deep Water (mCDW) towards the Totten ice shelf (TIS) region, with weakening of the ASC leading to enhanced on-shelf intrusions. Additionally, heat intrusions onto the TIS continental shelf are not influenced by off-shelf warming but rather by coastal freshening, indicating a positive feedback mechanism where ice melt and freshening upstream could trigger a chain reaction of increased melt and further coastal freshening.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geography, Physical
Zhujun Wan, Yetang Wang, Shugui Hou, Baojuan Huai, Qi Liu
Summary: This study quantified glacier mass-balance changes in the Karlik Range in the eastern Tien Shan over the time spans of 1972-2000 and 2000-2015, revealing significant mass loss with an acceleration in the early 21st century, largely attributed to regional warming.
JOURNAL OF GLACIOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Irena Vankova, Sue Cook, J. Paul Winberry, Keith W. Nicholls, Benjamin K. Galton-Fenzi
Summary: A phase-sensitive radar deployed on the Totten Ice Shelf provided the first in situ basal melt estimate, highlighting the dynamic significance of this East Antarctic ice shelf. The study emphasized the need for independent melt rate estimates using complementary instrumentation and techniques, given the differences in basal melt estimates among various methods.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geography, Physical
Andrew Nolan, William Kochtitzky, Ellyn M. Enderlin, Robert McNabb, Karl J. Kreutz
Summary: The study reveals that glacier surges on the Sit' Kusa (Turner Glacier) in the St. Elias Mountains of Alaska have a short recurrence interval and high velocities, possibly driven by periodic changes in subglacial hydrology and glacier sliding. Glacier surges result in thinning of the reservoir zone and thickening at the terminus, with a kinematic disconnect observed between the upper and lower regions near an icefall.
JOURNAL OF GLACIOLOGY
(2021)
Article
Environmental Sciences
Eleri Evans, Alexander D. Fraser, Sue Cook, Richard Coleman, Ian Joughin
Summary: Methods to estimate the calving flux of an ice shelf either capture the movement of the calving-front location or assume the calving front is stationary. Overcoming issues like temporal aliasing can be achieved by combining different methods.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Julia Liu, Ellyn Enderlin, Hans-Peter Marshall, Andre Khalil
Summary: Scientific attention has recently focused on estimating Greenland's dynamic mass loss, with a specific emphasis on its marine outlet glaciers. The study finds that dynamic mass loss for ice sheet outlet glaciers is highly sensitive to changes in climate and individual glacier geometry. However, dynamic mass loss for ice-sheet-independent marine glaciers around Greenland has been overlooked. Through the use of satellite imagery, the researchers were able to determine the highly detailed records of length changes for 135 peripheral marine glaciers in southeast Greenland. The observations revealed that these independent marine glaciers exhibited widespread, rapid, and synchronous response to increased meltwater input in 2016, suggesting they may be more sensitive to atmospheric warming than previously believed.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geography, Physical
Lisa Craw, Felicity S. McCormack, Sue Cook, Jason Roberts, Adam Treverrow
Summary: Understanding the behavior of ice shelves, particularly the influence of marine ice, is crucial for predicting the contribution of ice sheets to sea level rise. This study found that the thermal distribution of ice shelves has a greater effect on ice mass flux and thinning than the mechanical properties of marine ice.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geography, Physical
Katherine E. Bollen, Ellyn M. Enderlin, Rebecca Muhlheim
Summary: Over the past two decades, global glacier mass balance has decreased rapidly, with peripheral glaciers and ice caps in Greenland contributing significantly to the ice loss. While surface meltwater runoff has been estimated, the quantification of ice discharge into oceans remains unknown. By using the flux gate method, researchers estimated the discharge from Greenland's marine-terminating glaciers between 1985 and 2018 and found a significant increase in dynamic mass loss from synchronous widespread acceleration. The majority of this mass loss came from the southeast region of Greenland.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Irena Vankova, J. Paul Winberry, Sue Cook, Keith W. Nicholls, Chad A. Greene, Benjamin K. Galton-Fenzi
Summary: We deployed autonomous phase-sensitive radars on Totten Glacier's ice shelf to monitor ice-ocean interactions and made seismic observations to constrain gravity-derived bathymetry models. Our study finds an asymmetry in basal melting and reveals its correlation with water column thickness asymmetry. The importance of bathymetry near grounding lines for accurate ice-shelf melt modeling and the need for sustained multi-year monitoring, especially in ice-shelf cavities with varying dominant melt rate drivers, are highlighted.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Mechanics
Christian Schoof, Sue Cook, Bernd Kulessa, Sarah Thompson
Summary: Supraglacial lakes are important for storing melt water, enhancing surface melt, and driving ice flow and ice shelf melt. A model is developed to study the drainage of these lakes through a surface channel. The model considers flow in the channel, fueled by an upstream lake reservoir, and factors such as advection velocity, uplift, and channel wall roughness. Depending on the water supply rate, lake drainage can occur leading to either full depletion or oscillatory cycles of filling and draining.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Geography, Physical
Rainey Aberle, Ellyn M. Enderlin, Hans-Peter Marshall, Michal Kopera, Tate G. Meehan
Summary: The widespread retreat of glaciers and collapse of ice shelves on the Antarctic Peninsula are caused by global warming. Although some former tributary glaciers of the Larsen A and B ice shelves have re-advanced, their response to future climate change will be less significant compared to the initial collapse. Despite uncertainties in past and future climate forcing, simulations suggest a relatively modest range in grounding line discharge for Crane Glacier by 2100.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geography, Physical
Sue Cook, Keith W. Nicholls, Irena Vankova, Sarah S. Thompson, Benjamin K. Galton-Fenzi
Summary: Ocean-driven melt of Antarctic ice shelves is a complex phenomenon with significant spatial and temporal variability. This study evaluates the strengths and weaknesses of satellite and field-based observations for studying ice-shelf melt and highlights the underutilized potential of combining these data with model simulations. Furthermore, community initiatives to compile and publish coordinated melt rate datasets are identified as valuable resources for validating satellite-derived maps and improving numerical simulations.
ANNALS OF GLACIOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Chris Miele, Timothy C. Bartholomaus, Ellyn M. Enderlin
Summary: Along the margins of floating ice shelves in Greenland and Antarctica, the flow of ice is often accompanied by extensive rifting. These rifts propagate inward and are responsible for many large-scale calving events. By analyzing velocity maps, it has been found that the flow through these regions transitions from confined to unconfined ice shelf flow. The decrease in marginal resistance and the accompanying near-margin tension explain the occurrence of full-thickness rifts, indicating that progressive decoupling is a primary factor in ice shelf calving.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Geography, Physical
Lisa Craw, Adam Treverrow, Sheng Fan, Mark Peternell, Sue Cook, Felicity McCormack, Jason Roberts
Summary: Understanding the mechanical properties of flowing ice is crucial for modeling ice dynamics and predicting future behavior. By conducting deformation experiments on ice in laboratories, we can enhance our understanding of its physical properties. Changing the temperature mid-experiment can reduce total run-time without significant bias in results, with noticeable microstructural differences observed between smaller and larger temperature step experiments.