Article
Environmental Sciences
DongYoub Shin, Doshik Hahm, Tae-Wan Kim, Tae Siek Rhee, SangHoon Lee, Keyhong Park, Jisoo Park, Young Shin Kwon, Mi Seon Kim, Tongsup Lee
Summary: This study used multiparameter analysis to delineate the distribution of glacial meltwater in the Dotson-Getz Trough. By increasing the number of tracers, the researchers were able to identify potential source waters and determine the proportions of different types of meltwater. The results showed that submarine meltwater was most abundant at a depth of around 450 m near the Dotson Ice Shelf, while air-equilibrated freshwater and surface melts were present in the surface layer. The study also found that separating different sources of meltwater allowed for the estimation of basal melting rates for adjacent ice shelves.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Kaitlin A. Naughten, Paul R. Holland, Jan De Rydt
Summary: Ocean-driven melting of floating ice-shelves in the Amundsen Sea is the main process controlling Antarctica's contribution to sea-level rise. Rapid ocean warming, at approximately triple the historical rate, is likely to continue throughout the 21st century, leading to increased ice-shelf melting and potential collapse of the West Antarctic Ice Sheet, despite efforts to mitigate greenhouse gases.
NATURE CLIMATE CHANGE
(2023)
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
Geosciences, Multidisciplinary
Alessandro Silvano, Paul R. Holland, Kaitlin A. Naughten, Oana Dragomir, Pierre Dutrieux, Adrian Jenkins, Yidongfang Si, Andrew L. Stewart, Beatriz Pena Molino, Gregor W. Janzing, Tiago S. Dotto, Alberto C. Naveira Garabato
Summary: Warm ocean waters drive rapid ice-shelf melting in the Amundsen Sea. The variability of the undercurrent, which transports warm waters onto the continental shelf, is found to be depth-dependent on decadal time scales. Decadal ocean surface cooling in the tropical Pacific leads to wind anomalies that drive a perturbation of the surface flow and undercurrent, resulting in increased ice-shelf melting.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
A. G. Twelves, D. N. Goldberg, S. F. Henley, M. R. Mazloff, D. C. Jones
Summary: The study found that ice shelf melting directly and indirectly increases the upper ocean iron concentration, impacting NPP; phytoplankton self-shading feedback delays the spring bloom and reduces NPP; iron limitation is more important later in the season, higher in the water column, and further from the ice shelf.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Chemistry, Multidisciplinary
Mi Hae Jeon, Jinyoung Jung, Mi Ok Park, Shigeru Aoki, Tae-Wan Kim, Seung-Kyu Kim
Summary: The Amundsen Sea is experiencing rapid melting of the West Antarctic Ice Sheet due to increased heat transport by Circumpolar Deep Water (CDW). Studying the humic-like component of fluorescent dissolved organic matter (FDOM) as a tracer for CDW and glacial meltwater in the Amundsen Sea shows potential for identifying these water masses and their impacts on biogeochemical cycles.
Article
Geosciences, Multidisciplinary
Jun-Oh Min, Sung-Han Kim, Jinyoung Jung, Ui-Jung Jung, Eun Jin Yang, SangHoon Lee, Jung-Ho Hyun
Summary: The study reveals the tight coupling between glacial meltwater and heterotrophic bacterial production on the Getz Ice Shelf in the Antarctic Amundsen Sea, with higher BP in the eastern Getz Ice Shelf mainly attributed to meltwater-derived dissolved organic carbon. This suggests that warming-induced glacier melting may weaken carbon sequestration efficiency in Antarctic coastal waters by stimulating heterotrophic metabolism.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
L. M. Schulze Chretien, A. F. Thompson, M. M. Flexas, K. Speer, N. Swaim, R. Oelerich, X. Ruan, R. Schubert, C. LoBuglio
Summary: Our results show that the Bellingshausen Sea is a critical part of the larger West Antarctic circulation system, linking the WAP and the Amundsen Sea.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Biology
Bo Wang, Lingfang Fan, Minfang Zheng, Yusheng Qiu, Min Chen
Summary: In the Amundsen Sea, sea ice meltwater has a more pronounced effect on phytoplankton growth than meteoric water. Sea ice formation inhibits carbon fixation, resulting in a higher Fe/C ratio in phytoplankton. Freshwater inputs in the Southern Ocean influence phytoplankton growth by affecting water stability and providing dissolved iron (DFe).
Article
Geosciences, Multidisciplinary
Elena Savidge, Tasha Snow, Matthew R. Siegfried
Summary: In this study, a multi-decadal record of polynya area at Pine Island Glacier (PIG) was generated using satellite imagery. The results showed significant interannual variability in polynya area, with the largest polynya occurring at the western edge of PIG just before a large iceberg calved. This suggests that polynya size and position may influence iceberg calving.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Harriet C. P. Lau
Summary: Ice mass and sea-level changes induce glacial isostatic adjustment (GIA) at different timescales. The solid Earth is usually treated as a Maxwell viscoelastic solid for long-term GIA predictions and as an elastic solid for short-term events. However, experimental results suggest that transient deformation occurs at intermediate timescales, which cannot be captured by existing models. By using experimentally constrained viscoelastic models, this study explores transient deformation in GIA and sea-level change predictions, specifically focusing on Meltwater Pulse 1A (MWP-1A). The results reveal significant deviations from the Maxwell model and emphasize the need to revisit the source of MWP-1A and similar events.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Peter M. F. Sheehan, Karen J. Heywood, Andrew F. Thompson, M. Mar Flexas, Michael P. Schodlok
Summary: The content and pathways of meltwater determine the impact of melting ice shelves in Antarctica on ocean circulation and climate. Through observations and simulations, we found that meltwater from different ice shelves has different densities and turbidities, leading to separate export pathways. The observations revealed a cyclonic in-trough gyre that retains meltwater, which has the potential to affect circulation and future melting.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
H. W. Yang, T-W Kim, Pierre Dutrieux, A. K. Wahlin, Adrian Jenkins, H. K. Ha, C. S. Kim, K-H Cho, T. Park, S. H. Lee, Y-K Cho
Summary: This study investigates the seasonal variability and local forcing for the currents moving into and out of the Dotson ice shelf cavity using data from three bottom-mounted mooring arrays. It reveals that warm, salty water flows southward along the eastern channel slope, with maximum current velocities. On the other hand, freshened ice shelf meltwater flows northward at intermediate depth above the western slope. The inflow is correlated with local ocean surface stress curl, while the outflow follows the warm influx with a delay of about 2-3 months. Ocean circulation near Dotson Ice Shelf, affected by sea ice distribution and wind, significantly controls the inflow of warm water and subsequent ice shelf melting on seasonal time-scales.
NATURE COMMUNICATIONS
(2022)
Article
Environmental Sciences
Lu-Sha Yu, Hailun He, Hengling Leng, Hailong Liu, Pengfei Lin
Summary: This study investigates the interannual variability of January sea surface temperature (SST) in the Amundsen Sea during the period 1982-2022. The research finds that SST in the Pine Island Bay exhibits the most significant interannual variation, with a standard deviation up to 0.6 degrees. The study identifies the possible mechanism of anomalous January SST in the Pine Island Bay, which could provide an important clue for seasonal forecasts of summer SST in the Amundsen Sea.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Multidisciplinary Sciences
M. Mar Flexas, Andrew F. Thompson, Michael P. Schodlok, Hong Zhang, Kevin Speer
Summary: The observed acceleration of ice shelf basal melt rates throughout West Antarctica could destabilize continental ice sheets and markedly increase global sea level. Explanations for decadal-scale melt intensification have focused on processes local to shelf seas surrounding the ice shelves. A suite of process-based model experiments, guided by CMIP6 forcing scenarios, show that freshwater forcing from the Antarctic Peninsula, propagated between marginal seas by a coastal boundary current, causes enhanced melting throughout West Antarctica.
Article
Oceanography
Ryan D. D. Patmore, Paul R. R. Holland, Catherine A. A. Vreugdenhil, Adrian Jenkins, John R. R. Taylor
Summary: The ice shelf-ocean boundary current plays a crucial role in heat delivery to the base of an ice shelf. This study models the current using a nonhydrostatic z-level configuration at a turbulence-permitting resolution. The results show that the z-level model accurately represents the physics and can be used for turbulence closure. The study also demonstrates the effects of grid resolution and interactive melting on the system.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2023)
Review
Chemistry, Multidisciplinary
Jan Kaiser, David Brynn Hibbert, Juergen Stohner
PURE AND APPLIED CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Peter E. D. Davis, Keith W. Nicholls, David M. Holland, Britney E. Schmidt, Peter Washam, Kiya L. Riverman, Robert J. Arthern, Irena Vankova, Clare Eayrs, James A. Smith, Paul G. D. Anker, Andrew D. Mullen, Daniel Dichek, Justin D. Lawrence, Matthew M. Meister, Elisabeth Clyne, Aurora Basinski-Ferris, Eric Rignot, Bastien Y. Queste, Lars Boehme, Karen J. Heywood, Sridhar Anandakrishnan, Keith Makinson
Summary: Thwaites Glacier in Antarctica is undergoing rapid and irreversible ice loss due to the unknown ocean conditions and basal melting in the grounding-zone region. The warm and stable water column at the grounding zone restricts the vertical mixing of heat, resulting in suppressed basal melting. The conventional model for predicting sea-level rise cannot explain the observed melt rates beneath this crucial glacier.
Article
Multidisciplinary Sciences
James R. Jordan, B. W. J. Miles, G. H. Gudmundsson, S. S. R. Jamieson, A. Jenkins, C. R. Stokes
Summary: The East Antarctic Ice Sheet is currently surrounded by cool water, but changes in ocean dynamics may bring warmer water in the future. This could greatly increase its contribution to sea level rise.
NATURE COMMUNICATIONS
(2023)
Article
Oceanography
Marina Azaneu, Benjamin Webber, Karen J. Heywood, Karen M. Assmann, Tiago S. Dotto, E. Povl Abrahamsen
Summary: The heat transported by Circumpolar Deep Water (CDW) onto the continental shelf is the main factor driving ice shelf basal melting in the Amundsen Sea. Variability on intermonthly time scales is observed in the onshore heat flux, primarily driven by zonal wind stress. The central and eastern troughs are dynamically linked by the zonal wind stress forcing, and during the El Nino of 2015/2016, intensified onshore heat flux is observed in the eastern Amundsen Sea due to strengthened eastward undercurrent and upwelling of colder and deeper CDW variety.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Oceanography
Michael Haigh, Paul R. Holland, Adrian Jenkins
Summary: Ice streams such as Pine Island and Thwaites Glaciers in the eastern Amundsen Sea are losing mass rapidly due to basal melting influenced by deep ocean currents. This study examines the role of bathymetric features in shelf-wide circulation and heat transport onto the continental shelf. Understanding these processes is crucial for future research and modeling.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Oceanography
J. Anselin, B. C. Reed, A. Jenkins, J. A. M. Green
Summary: Tidal currents affect the basal melting of Antarctic ice shelves through local processes within the boundary current and far-field processes within the cavity. The separate effects of these processes are poorly understood, hindering the parameterization of tide-driven interactions. This study focuses on small-scale processes within the boundary current and finds that tides can either increase or decrease melt rates depending on the representation of tidal mixing processes.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Geosciences, Multidisciplinary
Peter M. F. Sheehan, Karen J. Heywood, Andrew F. Thompson, M. Mar Flexas, Michael P. Schodlok
Summary: The content and pathways of meltwater determine the impact of melting ice shelves in Antarctica on ocean circulation and climate. Through observations and simulations, we found that meltwater from different ice shelves has different densities and turbidities, leading to separate export pathways. The observations revealed a cyclonic in-trough gyre that retains meltwater, which has the potential to affect circulation and future melting.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Alice C. Fremand, Peter Fretwell, Julien A. Bodart, Hamish D. Pritchard, Alan Aitken, Jonathan L. Bamber, Robin Bell, Cesidio Bianchi, Robert G. Bingham, Donald D. Blankenship, Gino Casassa, Ginny Catania, Knut Christianson, Howard Conway, Hugh F. J. Corr, Xiangbin Cui, Detlef Damaske, Volkmar Damm, Reinhard Drews, Graeme Eagles, Olaf Eisen, Hannes Eisermann, Fausto Ferraccioli, Elena Field, Rene Forsberg, Steven Franke, Shuji Fujita, Yonggyu Gim, Vikram Goel, Siva Prasad Gogineni, Jamin Greenbaum, Benjamin Hills, Richard C. A. Hindmarsh, Andrew O. Hoffman, Per Holmlund, Nicholas Holschuh, John W. Holt, Annika N. Horlings, Angelika Humbert, Robert W. Jacobel, Daniela Jansen, Adrian Jenkins, Wilfried Jokat, Tom Jordan, Edward King, Jack Kohler, William Krabill, Mette Kusk Gillespie, Kirsty Langley, Joohan Lee, German Leitchenkov, Carlton Leuschen, Bruce Luyendyk, Joseph MacGregor, Emma MacKie, Kenichi Matsuoka, Mathieu Morlighem, Jeremie Mouginot, Frank O. Nitsche, Yoshifumi Nogi, Ole A. Nost, John Paden, Frank Pattyn, Sergey V. Popov, Eric Rignot, David M. Rippin, Andres Rivera, Jason Roberts, Neil Ross, Anotonia Ruppel, Dustin M. Schroeder, Martin J. Siegert, Andrew M. Smith, Daniel Steinhage, Michael Studinger, Bo Sun, Ignazio Tabacco, Kirsty Tinto, Stefano Urbini, David Vaughan, Brian C. Welch, Douglas S. Wilson, Duncan A. Young, Achille Zirizzotti
Summary: One of the key components of this research is to map Antarctic bed topography and ice thickness parameters, which are crucial for modeling ice flow and predicting future ice loss and sea level rise. The Bedmap3 Action Group, supported by SCAR, aims to produce new gridded maps and make geophysical survey data points available for the international scientific community. They have introduced the SCAR Bedmap Data Portal to provide open access to these datasets. This data release is expected to greatly benefit Antarctic research and extend the life cycle of the data.
EARTH SYSTEM SCIENCE DATA
(2023)
Article
Environmental Sciences
Amelia M. H. Bond, Markus M. Frey, Jan Kaiser, Jorg Kleffmann, Anna E. Jones, Freya A. Squires
Summary: Measurements were conducted to determine the amount fraction and flux density of atmospheric nitrous acid (HONO) above snow in Halley station, coastal Antarctica. The HONO amount fraction had a diurnal cycle, with a maximum at solar noon, and was generally lower than other Antarctic locations. The flux density of HONO from the snow was measured, showing a decrease at night and being close to the calculated HONO production rate. The study suggests that HONO snow emissions are a significant source of OH in the atmospheric boundary layer above Antarctic snowpacks.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Geosciences, Multidisciplinary
Pierre L'Hegaret, Florian Schuette, Sabrina Speich, Gilles Reverdin, Dariusz B. Baranowski, Rena Czeschel, Tim Fischer, Gregory R. Foltz, Karen J. Heywood, Gerd Krahmann, Remi Laxenaire, Caroline Le Bihan, Philippe Le Bot, Stephane Leizour, Callum Rollo, Michael Schlundt, Elizabeth Siddle, Corentin Subirade, Dongxiao Zhang, Johannes Karstensen
Summary: The EUREC4A-OA/ATOMIC experiment aimed to study the dynamic processes and interaction between the ocean and the atmosphere in the northwestern Tropical Atlantic Ocean. Multiple devices and platforms were used to gather data, which were calibrated and validated for consistency.
EARTH SYSTEM SCIENCE DATA
(2023)
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
Meteorology & Atmospheric Sciences
Peter M. F. Sheehan, Gillian M. Damerell, Philip J. Leadbitter, Karen J. Heywood, Rob A. Hall
Summary: Ocean gliders enable high-resolution microstructure observations for calculating turbulent kinetic energy dissipation rate, epsilon, on longer timescales than traditional ship-based platforms. In this study, we report the first detailed estimates of epsilon using the Batchelor spectrum and Thorpe scale methods on observations collected by a Seaglider. The two methods show good agreement, with the Thorpe scale method yielding slightly larger values of epsilon.
Article
Oceanography
Sybren S. Drijfhout, Christopher Y. S. Bull, Helene Hewitt, Paul R. Holland, Adrian Jenkins, Pierre Mathiot, Alberto Naveira Garabato
Summary: Mass loss from the Antarctic Ice Sheet is primarily caused by basal melting-induced warm ocean water. The Amundsen sector of the Antarctic continental shelf acts as a gateway, regulating the on-shelf access and westward transfer of warm Circumpolar Deep Water (CDW). Changes in temperature anomalies are mainly influenced by shifts in the Amundsen Sea Low, which are associated with tropical climate variability and modulate the on-shelf transport of CDW via wind-driven perturbations to ocean currents.
Article
Oceanography
S. Wahlgren, J. Thomson, L. C. Biddle, S. Swart
Summary: Wave energy has an impact on the quality and extent of sea ice in the Antarctic marginal ice zone, and understanding wave propagation is crucial for predicting changes in sea ice cover. In this study, new in situ data collected from drifting buoys in the Weddell Sea reveal season-dependent attenuation of swell and a change in wave direction in sea ice compared to open water. These observations provide valuable insights into wave-sea ice interactions and can aid the development of accurate models for representing the influence of sea ice on wave propagation.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)