Article
Geography, Physical
Timothy P. P. Lane, Christopher Darvill, Brice Rea, Mike Bentley, James A. A. Smith, Stewart Jamieson, Colm O. Cofaigh, David Roberts
Summary: Understanding ice stream dynamics is important for predicting ice sheet behavior. This study investigates the geomorphological imprint of ice shelves during deglaciation in northeast Greenland. The findings reveal the development of ice shelves, warm-based ice, and thinning of the grounded ice stream margin over time. The study also documents the expansion and retreat of the 79N ice shelf, providing insights into present-day ice shelf landsystem in a warming climate.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
J. D. Scourse, R. C. Chiverrell, R. K. Smedley, D. Small, M. J. Burke, M. Saher, K. J. J. Van Landeghem, G. A. T. Duller, C. O. Cofaigh, M. D. Bateman, S. Benetti, S. Bradley, L. Callard, D. J. A. Evans, D. Fabel, G. T. H. Jenkins, S. McCarron, A. Medialdea, S. Moreton, X. Ou, D. Praeg, D. H. Roberts, H. M. Roberts, C. D. Clark
Summary: The BRITICE-CHRONO Project has compiled and analyzed data on ice retreat dynamics in the Celtic and Irish seas, finding that the pace of deglaciation is influenced more by topography and internal ice dynamics than external factors. This research suggests that the retreat of the Irish Sea Ice Stream was rapid and short-lived, leading to the formation of an extensive dead ice landscape in the English Midlands.
JOURNAL OF QUATERNARY SCIENCE
(2021)
Article
Geography, Physical
Nina Aradottir, Ivar Oern Benediktsson, Olafur Ingolfsson, Skafti Brynjolfsson, Wesley R. Farnsworth, Margret Mjoell Benjaminsdottir, Lena Bjoerg Rikhardsdottir
Summary: This study focuses on the shutdown phase of ice streams during deglaciation, which is different from their active flow phase. Mapping of streamlined subglacial bedforms in northeast Iceland reveals the presence of crevasse-squeeze ridges, indicating ice stagnation and waning of ice streaming during the Younger Dryas period. The morphological differences of these ridges suggest different kinematic settings within the ice streams.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
Shannon M. Hibbard, Gordon R. Osinski, Etienne Godin
Summary: Conspicuous Vermicular Ridge Features (VRFs) with unique morphology have been discovered along the coast of Dundas Harbour, Devon Island, Nunavut, Canada. These features are believed to be ring-ridge moraines formed by paraglacial processes, representing a first documentation of such features in Nunavut, Canada.
Article
Multidisciplinary Sciences
Jostein Bakke, Oyvind Paasche, Joerg M. Schaefer, Axel Timmermann
Summary: The accelerated melting of ice on the Antarctic Peninsula and sub-Antarctic islands indicates the cryosphere is approaching an irreversible tipping point. Research on South Georgia Island reveals that glaciers have been gradually retreating since the Antarctic cold reversal, with a link to summer insolation at 55°S and multi-decadal to centennial climate shifts causing at least nine glacier readvances in the past 10.5 ka.
SCIENTIFIC REPORTS
(2021)
Article
Geography, Physical
Carl Regnell, Gustaf Peterson Becher, Christian Ohrling, Sarah L. Greenwood, Richard Gyllencreutz, Robin Blomdin, Jo Brendryen, Bradley W. Goodfellow, Henrik Mikko, Gunnel Ransed, Colby Smith
Summary: Using high-resolution LiDAR, researchers have identified over 4500 relict shorelines, deltas, and palaeo-channels related to ice-dammed lakes in central Jaeuromtland, west-central Sweden. They reconstructed the evolution of the lakes and the retreating ice margin, which resulted in the formation of a single lake and a large glacial lake outburst flood. The study also suggests a correlation between the lake drainage events and the Swedish Time Scale.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Geosciences, Multidisciplinary
Conner J. C. Adams, Neal R. Iverson, Christian Helanow, Lucas K. Zoet, Charlotte E. Bate
Summary: Ice at depth in ice-stream shear margins is believed to be commonly temperate with interstitial meltwater that softens the ice. Experimental studies show that water softening amplifies basal slip and significantly affects the effective viscosity of ice.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
S. -K. Kufner, J. Wookey, A. M. Brisbourne, C. Martin, T. S. Hudson, J. M. Kendall, A. M. Smith
Summary: The crystal orientation fabric of glacier ice is crucial in determining its strength and flow behavior, making it an important factor in ice flow modeling. In this study, the authors demonstrate that shear-wave splitting (SWS) measured through glacial microseismicity can be used to infer seismic anisotropy and ice fabric in a statistical sense. By analyzing over 200,000 SWS measurements from a seismic network near Rutford Ice Stream in Antarctica, the researchers were able to identify a three-layer ice fabric structure with varying strengths and deformability along the flow direction. Their findings suggest that fast-flowing ice streams may require a more complex integration of viscosity in ice sheet models.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Geosciences, Multidisciplinary
Holly Still, Christina Hulbe, Martin Forbes, David J. Prior, M. Hamish Bowman, Bia Boucinhas, Lisa Craw, Daeyeong Kim, Franz Lutz, Robert Mulvaney, Rilee E. Thomas
Summary: This study investigates ice deformation in Priestley Glacier, Antarctica, using high-resolution, ground-based observations. The results show that the pattern of ice displacement and strain depends on the coupling between the ice and valley sidewall, as well as the tidal forces causing the displacement.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Brittany N. Price, Nathan D. Stansell, Alfonso Fernandez, Joseph M. Licciardi, Alia J. Lesnek, Ariel Munoz, Mary K. Sorensen, Edilia Jaque Castillo, Tal Shutkin, Isabella Ciocca, Ianire Galilea
Summary: The development of robust chronologies of Neoglaciation in the high-altitude Andes can provide valuable insights into regional climate variability and aid in predicting future changes. Unfortunately, records of Late Holocene glaciation in the Central Chilean Andes are limited. In this study, we used a combination of dating techniques to establish a chronology of glacier fluctuations and found evidence of coeval climate variability between the middle and high southern latitudes during the Late Holocene.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geography, Physical
Bethan Davies, Jacob Bendle, Jonathan Carrivick, Robert McNabb, Christopher McNeil, Mauri Pelto, Seth Campbell, Tom Holt, Jeremy Ely, Bradley Markle
Summary: Mountain glaciers and ice caps are losing significant amounts of ice globally, with Alaska contributing greatly to sea-level rise. This study focuses on Alaskan plateau icefields and their vulnerability to climate change. The researchers conducted an inventory of glaciers and lakes in the Juneau Icefield region, finding that 63 glaciers disappeared since 2005, with a 10.0% reduction in glacier area. The study also presents the first structural glaciological and geomorphological map of an entire icefield in Alaska, showing widespread glacier disconnections and continuous recession since the Little Ice Age. The findings highlight the importance of considering glacier disconnections when evaluating icefield vulnerability to climate change.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Geography, Physical
E. Lebas, R. Gromig, S. Krastel, B. Wagner, G. Fedorov, C. Goertz, T. Averes, D. Subetto, M. Naumenko, M. Melles
Summary: Seismic reflection data and sediment core data provide insight into the environmental and sedimentological history of Lake Ladoga since the late Quaternary, including basin bedrock reshaping, post-glacial mound formation, deglaciation sedimentation, and Holocene lacustrine sedimentation. Major fault systems and unconformities related to lake-level fluctuations were also identified in the study.
QUATERNARY SCIENCE REVIEWS
(2021)
Article
Geosciences, Multidisciplinary
Ian Delaney, Leif S. Anderson
Summary: Debris in glaciers affects their shape and movement, reducing ice melt and potentially leading to conditions for glacier surging.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Aslak Grinsted, Christine S. Hvidberg, David A. Lilien, Nicholas M. Rathmann, Nanna B. Karlsson, Tamara Gerber, Helle Astrid Kjaer, Paul Vallelonga, Dorthe Dahl-Jensen
Summary: A new study reveals the instability of the North East Greenland ice stream and its potential impact on future evolution. By analyzing remote sensing data and GPS observations, researchers find that the shear margins of the ice stream are accelerating and widening, which is likely due to the softening of the shear margin caused by evolving fabric or temperature, rather than external forcing.
NATURE COMMUNICATIONS
(2022)
Article
Geography, Physical
Mikis van Boeckel, Tayo van Boeckel, Adrian M. Hall
Summary: The arrival of meltwater during deglaciation can transform subglacial conditions and result in significant reworking and erosion of rock and sediment.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Geography, Physical
Jeremy C. Ely, Chris D. Clark, Richard C. A. Hindmarsh, Anna L. C. Hughes, Sarah L. Greenwood, Sarah L. Bradley, Edward Gasson, Lauren Gregoire, Niall Gandy, Chris R. Stokes, David Small
Summary: Comparing numerical model simulations with empirical evidence helps quantify the degree of fit between the two, leading to more accurate reconstructions of palaeo-ice sheets. Reconciling numerical modelling and empirical evidence is crucial for achieving palaeo-ice sheet reconstructions with greater explanatory and predictive power.
JOURNAL OF QUATERNARY SCIENCE
(2021)
Article
Geography, Physical
Emily A. Hill, G. Hilmar Gudmundsson, J. Rachel Carr, Chris R. Stokes, Helen M. King
Summary: Thinning or collapse of ice shelves can accelerate ice flow, increase ice discharge, and raise global mean sea levels. The response of Petermann Glacier to total ice shelf loss is uncertain, but it is likely to have minimal impact on global mean sea level. Further research is needed to understand the sensitivity of the glacier to ice shelf changes in the future.
JOURNAL OF GLACIOLOGY
(2021)
Article
Geography, Physical
Jennifer F. Arthur, Chris R. Stokes, Stewart S. R. Jamieson, Bertie W. J. Miles, J. Rachel Carr, Amber A. Leeson
Summary: The study found that the rapid disintegration of the ice tongue in East Antarctica in March to May 2007 was preconditioned by the weakening of structural integrity and triggered by regional atmospheric circulation anomaly and less extensive latent-heat multi-year sea ice. Disaggregation did not lead to inland ice flow acceleration, but highlighted the importance of interactions between sea ice, melange, and ice shelves.
JOURNAL OF GLACIOLOGY
(2021)
Article
Geography
J. R. Leigh, D. J. A. Evans, C. R. Stokes, L. M. Andreassen, R. J. Carr
Summary: The map presents the glacial and periglacial geomorphology of a 6800 km(2) region in Arctic Norway, reconstructed through manual digitisation and satellite imagery. Over 20,000 individual features were mapped, providing valuable data for understanding the region's glacial history during the Holocene.
Article
Geosciences, Multidisciplinary
April S. Dalton, Chris R. Stokes, Christine L. Batchelor
Summary: By synthesizing geochronological data, stratigraphic and geomorphological data, as well as numerical modeling output, we reconstructed the Laurentide and Innuitian ice sheets during the last glacial cycle. Our findings suggest that there were multiple cycles of rapid ice sheet growth and decay in different areas of North America between 115 ka and 25 ka, leading to significant changes in global mean sea level and landscape evolution.
EARTH-SCIENCE REVIEWS
(2022)
Article
Geography, Physical
James R. Jordan, G. Hilmar Gudmundsson, Adrian Jenkins, Chris R. Stokes, Bertie W. J. Miles, Stewart S. R. Jamieson
Summary: Recent observations in the Wilkes Subglacial Basin in East Antarctica show an acceleration in ice speed over the grounding line of Cook Glacier since the 1970s. Numerical simulations indicate that the acceleration of Cook Glacier is linked to changes in calving front position, ice shelf thinning, and grounding line retreat.
JOURNAL OF GLACIOLOGY
(2022)
Article
Multidisciplinary Sciences
Jennifer F. Arthur, Chris R. Stokes, Stewart S. R. Jamieson, J. Rachel Carr, Amber A. Leeson, Vincent Verjans
Summary: Observations of Antarctic supraglacial lakes (SGLs) are relatively scarce and their interannual variability is largely unknown. This study provides the first observations of SGLs across the entire East Antarctic Ice Sheet over multiple melt seasons. The results show that SGL volume varies greatly from year to year on some ice shelves, with more extensive and deeper lakes associated with higher summer air temperatures. Model predictions suggest that January melt and the ratio of November firn air content to summer melt are important predictors of SGL volume on vulnerable ice shelves.
NATURE COMMUNICATIONS
(2022)
Review
Multidisciplinary Sciences
Chris R. Stokes, Nerilie J. Abram, Michael J. Bentley, Tamsin L. Edwards, Matthew H. England, Annie Foppert, Stewart S. R. Jamieson, Richard S. Jones, Matt A. King, Jan T. M. Lenaerts, Brooke Medley, Bertie W. J. Miles, Guy J. G. Paxman, Catherine Ritz, Tina van de Flierdt, Pippa L. Whitehouse
Summary: The East Antarctic Ice Sheet, which contains the majority of Earth's glacier ice, is considered less vulnerable to global warming compared to other ice sheets. However, recent mass loss in certain regions has prompted a re-evaluation of its sensitivity to climate change. While some marine-based catchments are currently losing mass, projections indicate increased accumulation in the East Antarctic Ice Sheet over the next century, maintaining overall balance. However, under high-emissions scenarios beyond 2100, significant ice discharge and sea-level rise could occur unless the Paris Agreement goals are met.
Article
Multidisciplinary Sciences
Bertie W. J. Miles, Chris R. Stokes, Stewart S. R. Jamieson, Jim R. Jordan, G. Hilmar Gudmundsson, Adrian Jenkins
Summary: The contribution of Antarctica's ice discharge to global mean sea level rise is influenced by various factors, including ice shelf buttressing and local glacier geometry. Understanding the spatial and temporal variability of ice discharge is crucial for predicting future sea level rise.
SCIENTIFIC REPORTS
(2022)
Editorial Material
Environmental Sciences
Astrid Lysa, Anne Jennings, Caterina Morigi, Chris R. Stokes, Monica C. M. Winsborrow
ARCTIC ANTARCTIC AND ALPINE RESEARCH
(2022)
Article
Geography, Physical
Mihaela Newton, Chris R. Stokes, David H. Roberts, David J. A. Evans
Summary: This study systematically maps, samples, and measures bedrock mega-grooves (BMGs) from ten locations worldwide. The results show that BMGs have consistent morphometric characteristics and are distinct from other subglacial landforms. The size, shape, and spacing of BMGs are influenced by site-specific geological characteristics. Future research should focus on numerical modeling experiments to further understand erosion rates and on expanding field observations.
Article
Geography, Physical
David J. A. Evans, Mihaela Newton, David H. Roberts, Chris R. Stokes
Summary: Understanding the origin and evolution of bedrock mega-grooves (BMGs) is crucial. This study proposes several scenarios to explain the initiation of parallel fluted terrain incised through resistant substrates by uni-directional fast ice flow. The initiation of BMGs is likely controlled by geological factors such as linear features or adjacent lithologies, while antecedent land surface conditions or pre-Quaternary regolith on etchplains may also contribute to their initiation.
Article
Geography, Physical
Bertie W. J. Miles, Chris R. Stokes, Adrian Jenkins, Jim R. Jordan, Stewart S. R. Jamieson, G. Hilmar Gudmundsson
Summary: Increased wind-forced intrusions of modified Circumpolar Deep Water (mCDW) have caused mass loss in West Antarctica and Wilkes Land, East Antarctica. However, observations in 2018 show that the Shirase Glacier in Enderby Land, East Antarctica has experienced a dynamical ocean-driven slowdown, ice surface thickening, and grounding line advance due to strengthening easterly winds that reduce mCDW inflow. This highlights the overlooked role of easterly winds in the recent mass gain of the Shirase Glacier catchment.
Article
Geography, Physical
Melanie Marochov, Chris R. Stokes, Patrice E. Carbonneau
Summary: There is a wealth of research on the key controls on mass loss from Greenland and Antarctic ice sheets in response to climate forcing, especially in relation to marine-terminating glacier change. Deep learning has advanced automated delineation of glacier calving fronts, but research is lacking in pixel-level semantic image classification of outlet glacier environments. A novel CNN-Supervised Classification workflow achieved high accuracy in classifying marine-terminating glaciers in Greenland and demonstrated robustness in complex imagery.
Article
Geography, Physical
Bertie W. J. Miles, Jim R. Jordan, Chris R. Stokes, Stewart S. R. Jamieson, G. Hilmar Gudmundsson, Adrian Jenkins
Summary: Research shows that the Denman Glacier has been accelerating overall since the 1970s, indicating that its recent changes may be related to factors such as grounding line retreat, ice thinning, and ice tongue detachment. Numerical modeling suggests that the Denman Glacier could potentially make a significant contribution to sea level rise in the near future.