Article
Geography, Physical
Santiago Munevar Garcia, Lauren Elizabeth Miller, Francesca Anna Maria Falcini, Leigh Asher Stearns
Summary: Spatial variability in bed roughness, which impacts ice-sheet flow and organization, is difficult to quantify due to sparse observations. This study uses high-resolution bathymetry data to analyze the spatial variability of bed roughness in formerly expanded glaciers across the Antarctic continental shelf, highlighting the importance of standardized characterization of topographic variability.
JOURNAL OF GLACIOLOGY
(2023)
Article
Multidisciplinary Sciences
Meghana Ranganathan, Jack-William Barotta, Colin R. Meyer, Brent Minchew
Summary: Liquid water within glacier ice and at the glacier beds plays a significant role in ice flow and stability. Meltwater from regions of rapid deformation, including shear margins, can affect the rheology of the ice and lubricate the bed. This study estimates the flux of meltwater from shear margins in three Antarctic regions and finds that it can be as significant as meltwater produced by frictional heating at the bed.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Engineering, Environmental
Morimaru Kida, Nobuhide Fujitake, Taichi Kojima, Yukiko Tanabe, Kentaro Hayashi, Sakae Kudoh, Thorsten Dittmar
Summary: Accelerated glacier melt and runoff contribute labile dissolved organic matter (DOM) into downstream ecosystems, where it undergoes substantial processing and transformation before entering the ocean. Molecular and optical techniques reveal that glacial DOM is primarily composed of small microbial-derived biomolecules, which are processed downstream into more complex molecules. Lakes along the flow path enhance water residence time and facilitate DOM processing and production.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Geography, Physical
J. Gales, M. Rebesco, L. De Santis, A. Bergamasco, F. Colleoni, S. Kim, D. Accettella, V. Kovacevic, Y. Liu, E. Olivo, E. Colizza, C. Florindo-Lopez, F. Zgur, R. McKay
Summary: The increased ocean heat supply to the Antarctic continental shelves is projected to accelerate ice sheet loss and significantly contribute to global sea-level rise in the coming decades. Changes in dense shelf water and other continental slope processes can influence submarine canyon morphology, with potential large-scale effects on atmospheric and oceanic circulation.
Article
Geosciences, Multidisciplinary
Natalie S. Barkdull, Gregory T. Carling, Diego P. Fernandez, Stephen T. Nelson, Barry R. Bickmore, David G. Tingey, Hannah N. Checketts, Brian N. Packer, Colin A. Hale
Summary: Glaciers alter the geochemistry and hydrology of alpine streams by exposing freshly weathered bedrock and releasing trace metals from melting ice. Research indicates that glacier meltwater significantly impacts water quality and hydrological characteristics.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geography, Physical
Aleksander Adamczyk, Wojciech Wysota, Jan A. Piotrowski
Summary: Glacial curvilineations (GCLs) are enigmatic landforms consisting of parallel winding ridges that have been discovered in the southern peripheral area of the last Scandinavian Ice Sheet (SIS). This study presents an inventory of GCLs along the SIS margin in Poland, Germany, and Denmark, and focuses on their geomorphic characteristics. The findings support the interpretation of GCLs as erosional remnants of antecedent landscapes carved by channelized subglacial meltwater flows.
Article
Ecology
Kornelia Anna Wojcik-Dlugoborska, Robert Jozef Bialik
Summary: The study examines the adaptation of existing algorithms to local conditions for marine polar observations using remote sensing data. Five satellite images and sixteen multispectral maps were analyzed to compare the Glacial Meltwater Turbidity Algorithm (GaMTA) with other algorithms for turbidity retrieval in heavily glaciated and open water areas. The results show that GaMTA performs better in small glacial coves with high and spatially varying surface water turbidity, while also showing applicability to aerial images.
REGIONAL STUDIES IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
B. Jack Pan, Michelle M. Gierach, Michael P. Meredith, Rick A. Reynolds, Oscar Schofield, Alexander J. Orona
Summary: This study develops a model for quantifying sea surface glacial meltwater (SSGM) using ocean color data, which shows accurate predictions and offers a novel method for studying and quantifying glacial meltwater in the Western Antarctic Peninsula (WAP) region.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Yoshihiro Nakayama, Cilan Cai, Helene Seroussi
Summary: The study shows that subglacial freshwater discharge significantly increases ice shelf melting rates, successfully simulating the high ice shelf melt rates suggested by observations. The buoyant mixture of glacial meltwater plume rises and spreads forward, affecting ocean circulation.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geography, Physical
Ryan Schubert, Andrew F. Thompson, Kevin Speer, Lena Schulze Chretien, Yana Bebieva
Summary: The West Antarctic Ice Sheet experiences basal melting induced by warm, salty Circumpolar Deep Water, resulting in the formation of the Antarctic Coastal Current (AACC). The AACC flows westward from the West Antarctic Peninsula towards the Bellingshausen Sea, impacting the export of water properties into the eastern Amundsen Sea. This current transports meltwater out of the Bellingshausen Sea and into the Amundsen and Ross seas, potentially affecting basal melt rates and bottom water formation in these regions.
Article
Water Resources
Philipp Wanner, Andreas Zischg, Christoph Wanner
Summary: This study aims to determine the opportunities and limitations of using stable water isotopes to quantify the glacial meltwater contribution to mountainous streams. The investigations revealed that the contribution of glacial meltwater to mountainous streams can be quantified using stable water isotopes if certain criteria are met. One of the three investigated catchments fulfilled these criteria and the glacial meltwater contribution to the mountainous streams could be estimated based on stable water isotopes. This study demonstrates the challenges and provides guidance for future stable water isotope studies in mountainous regions.
HYDROLOGICAL PROCESSES
(2023)
Article
Multidisciplinary Sciences
Yidongfang Si, Andrew L. Stewart, Ian Eisenman
Summary: The Antarctic Slope Front (ASF) is a strong gradient in water mass properties near the Antarctic margins, separating warm water from the Antarctic ice sheet. Heat transport across the ASF plays a crucial role in Earth's climate, affecting ice shelves melting, bottom water formation, and global meridional overturning circulation. Previous studies using low-resolution global models have contradictory findings on the impact of additional meltwater on heat transport toward the Antarctic continental shelf, and it remains unclear whether meltwater enhances shoreward heat transport or isolates the continental shelf from the open ocean. In this study, eddy- and tide-resolving simulations are used to investigate heat transport across the ASF, and it is found that freshening of coastal waters increases shoreward heat flux, indicating a positive feedback in a warming climate: increased meltwater leads to greater shoreward heat transport, causing further ice shelf melting.
Article
Ecology
Kiefer O. Forsch, Lisa Hahn-Woernle, Robert M. Sherrell, Vincent J. Roccanova, Kaixuan Bu, David Burdige, Maria Vernet, Katherine A. Barbeau
Summary: By studying the iron sources in a heavily glaciated western Antarctic Peninsula fjord, it is revealed that surface glacial melt and subglacial plumes contribute to the seasonal cycle of iron and manganese within the environment. The study also shows that organic ligands derived from phytoplankton and glaciers play a role in the dispersion of dissolved and particulate iron downstream, while buoyant plumes enriched in labile particulate trace metals supply iron to the fjord euphotic zone. Additionally, prolonged katabatic wind events enhance the export of meltwater out of the fjord, indicating an important atmosphere-ice-ocean coupling in coastal iron biogeochemistry and primary productivity along the WAP.
Article
Geosciences, Multidisciplinary
Calvin Shackleton, Henry Patton, Monica Winsborrow, Mariana Esteves, Lilja Bjarnadottir, Karin Andreassen
Summary: The flow of glacial ice is influenced by the fluctuation of basal meltwater drainage systems. Understanding the development of dominant drainage modes is crucial for predicting ice response to climate change. This study uses bathymetric data to map the geomorphology of meltwater drainage beneath the collapsing Barents Sea Ice Sheet. We find evidence of extensive channelized drainage networks and suggest that these systems were influenced by subglacial lakes. The abundance of meltwater during deglaciation likely contributed to erosion and sediment mobilization.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geography, Physical
Corinne L. Benedek, Ian C. Willis
Summary: Surface lakes on the Greenland Ice Sheet play a crucial role in its mass balance, hydrology, and biogeochemistry, often draining rapidly via hydrofracture which impacts subglacial drainage evolution and ice flow. Satellite imagery analysis reveals that rapid lake drainage events can occur not just in summer, but also in winter, influencing subglacial hydrology and biogeochemical processes.
Editorial Material
Geosciences, Multidisciplinary
Robert D. Larter
Summary: Ice shelves in Antarctica restrict the outflow of glaciers and limit the contribution to sea-level rise. However, past events have shown their vulnerability to melting, making it the largest uncertainty in predicting future sea-level rise. An analysis of ice-shelf roughness variations suggests a potential measure of the impact of basal melting on the structural integrity of ice shelves. Further research is needed to explore other contributing factors.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
K. A. Hogan, N. S. Arnold, R. D. Larter, J. D. Kirkham, R. Noormets, C. O. Cofaigh, N. R. Golledge, J. A. Dowdeswell
Summary: The subglacial hydrological system plays a crucial role in the behavior of ice sheets, but is difficult to observe. This study combines investigations and modeling to reveal the accumulation, routing, and erosion potential of subglacial water over long timescales. The findings support previous theories and present a viable pattern for subglacial drainage.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Environmental Sciences
Christine L. Batchelor, Betina A. Frinault, Frazer D. W. Christie, Aleksandr Montelli, Julian A. Dowdeswell
Summary: This study discovered over 240 pockmarks using high-resolution geophysical data along the north-east Antarctic Peninsula margin. The existence of these pockmarks could have significant implications for benthic biodiversity and the global carbon cycle.
Article
Geosciences, Multidisciplinary
Frazer D. W. Christie, Toby J. Benham, Christine L. Batchelor, Wolfgang Rack, Aleksandr Montelli, Julian A. Dowdeswell
Summary: The study finds that 85% of the seaward ice-shelf perimeter along the 1400-km-long eastern Antarctic Peninsula has experienced continuous advance between the early 2000s and 2019, in contrast to the two previous decades. This advance is attributed to enhanced ocean-wave dampening, ice-shelf buttressing, and the absence of sea-surface slope-induced gravitational ice-shelf flow. These phenomena are enabled by increased near-shore sea ice driven by a Weddell Sea-wide intensification of cyclonic surface winds around 2002. The findings demonstrate that sea-ice change can either protect or trigger the final rift and calving of even large Antarctic ice shelves.
Article
Geography, Physical
Zoe A. Roseby, James A. Smith, Claus-Dieter Hillenbrand, Claire S. Allen, Amy Leventer, Kelly Hogan, Matthieu J. B. Cartigny, Brad E. Rosenheim, Gerhard Kuhn, Robert D. Larter
Summary: This study investigates changes in biological productivity during the Last Glacial Transition (19-11 cal kyr BP) using sediment cores recovered from the Anvers-Hugo Trough (AHT), western Antarctic Peninsula shelf. The study reveals that seasonally open marine conditions were established by 13.6 cal kyr BP, but the accumulation of laminated diatomaceous oozes (LDOs) did not start until 11.5 cal kyr BP. The deposition of LDOs in AHT is associated with the early Holocene climatic optimum, increased atmospheric/ocean temperatures, high rates of sea and glacial ice melt, and the formation of a well-stratified water column.
QUATERNARY SCIENCE REVIEWS
(2022)
Article
Geosciences, Multidisciplinary
Christina S. Larkin, Mohamed M. Ezat, Natalie L. Roberts, Henning A. Bauch, Robert F. Spielhagen, Riko Noormets, Leonid Polyak, Steven G. Moreton, Tine L. Rasmussen, Michael Sarnthein, Edward T. Tipper, Alex M. Piotrowski
Summary: Neodymium isotope records reveal significant changes in deep-water formation and ocean circulation in the Nordic Seas and Arctic Ocean over the past 350,000 years. Deep-water formation was vigorous during the last glacial maximum but declined during deglaciation.
Article
Multidisciplinary Sciences
William Kochtitzky, Luke Copland, Wesley Van Wychen, Romain Hugonnet, Regine Hock, Julian A. Dowdeswell, Toby Benham, Tazio Strozzi, Andrey Glazovsky, Ivan Lavrentiev, David R. Rounce, Romain Millan, Alison Cook, Abigail Dalton, Hester Jiskoot, Jade Cooley, Jacek Jania, Francisco Navarro
Summary: This study estimated the frontal ablation of marine-terminating glaciers in the Northern Hemisphere and found that these glaciers contributed an average of 44.47 to 51.98 Gt of ice to the ocean annually from 2000 to 2020, making a significant contribution to sea-level rise.
NATURE COMMUNICATIONS
(2022)
Article
Geochemistry & Geophysics
Maximilian Lowe, Ben Mather, Chris Green, Tom A. Jordan, Joerg Ebbing, Robert Larter
Summary: Through high resolution magnetic airborne measurements, this study reveals the variations in crustal depth and geothermal heat flow distribution in the Transantarctic Mountains of Antarctica. The results indicate shallow Curie Point Depth (CPD) and high geothermal heat flow in the mountain range, supporting the hypothesis of thermal support of the topography.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Multidisciplinary Sciences
Christine L. Batchelor, Frazer D. W. Christie, Dag Ottesen, Aleksandr Montelli, Jeffrey Evans, Evelyn K. Dowdeswell, Lilja R. Bjarnadottir, Julian A. Dowdeswell
Summary: Rates of ice-sheet grounding-line retreat can be measured from the spacing of corrugation ridges on the seafloor, providing context for ice-sheet change. However, limited examples restrict our understanding of future retreat rates and sea-level rise.
Article
Geography, Physical
Kelly A. Hogan, Katarzyna L. P. Warburton, Alastair G. C. Graham, Jerome A. Neufeld, Duncan R. Hewitt, Julian A. Dowdeswell, Robert D. Larter
Summary: Improvements in sea-floor mapping techniques have revealed regular ridge landforms formed by the tidal flexure of ice-shelf grounding lines. Mathematical models based on sea-floor observations suggest that either till extrusion or resuspension and transport of grains contribute to the formation of these ridges. The simulations indicate that grounding line retreat rates may be even higher than previously thought, as overprinting of ridges occurs when realistic bed slopes are considered.
Article
Geochemistry & Geophysics
W. A. P. Smith, P. Lewinska, M. A. Cooper, E. R. Hancock, J. A. Dowdeswell, D. M. Rippin
Summary: This paper studies the problem of structure-from-motion for images with varying principal point. Initialization and pose estimation methods specific to this scenario are proposed and the performance is demonstrated on challenging real-world examples.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Geography, Physical
Michael A. Cooper, Paulina Lewinska, William A. P. Smith, Edwin R. Hancock, Julian A. Dowdeswell, David M. Rippin
Summary: This study presents an approach to extract quantifiable information from archival aerial photographs to extend the record of change in central eastern Greenland Ice Sheet. The insights gained from a longer record of ice margin change are crucial for understanding glacier response to climate change. The study also focuses on relatively small and understudied outlet glaciers from the eastern margin of the ice sheet, revealing significant heterogeneity in their response with non-climatic controls playing a key role.
Article
Environmental Sciences
Gabriele Uenzelmann-Neben, Karsten Gohl, Katharina Hochmuth, Ulrich Salzmann, Robert D. Larter, Claus-Dieter Hillenbrand, Johann P. Klages
Summary: Seismic imaging of a sediment drift on the Amundsen Sea Embayment shelf suggests that the growth of the West Antarctic Ice Sheet was hindered by the incursion of relatively warm circumpolar deep water as early as the Eocene-Oligocene transition. The study also concludes that the West Antarctic Ice Sheet has likely experienced a strong oceanic influence on its dynamics since its formation.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)