Article
Geosciences, Multidisciplinary
Wilton Aguiar, Sang-Ki Lee, Hosmay Lopez, Shenfu Dong, Helene Seroussi, Dani C. Jones, Adele K. Morrison
Summary: Melting of the ice sheet in the Southern Ocean has implications for the formation and properties of the Antarctic Bottom Water (AABW). Models have been used to examine the effects of different spatial distributions and magnitudes of meltwater fluxes on AABW. The study finds that a realistic and spatially varying meltwater flux can sustain AABW with higher salinities compared to uniform meltwater flux simulations. Furthermore, the increasing meltwater discharge from the Antarctic ice sheet can contribute to the observed freshening of AABW.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Oceanography
S. S. Jacobs, C. F. Giulivi, P. Dutrieux
Summary: A 63-year observational record in the southwest Ross Sea shows a continuous decrease in salinity and a slight warming. The freshening is mainly caused by a growing imbalance in meltwater from thinning ice shelves and increased iceberg calving, rather than sea ice production and stronger winds. The increase in meltwater is positively correlated with global atmospheric CO2 and temperature increases.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geosciences, Multidisciplinary
A. I. Ferola, Y. Cotroneo, P. Wadhams, G. Fusco, P. Falco, G. Budillon, G. Aulicino
Summary: Monitoring Antarctic sea-ice is crucial for understanding the Southern Ocean, and our study utilized satellite data from 2002-2020 to analyze the sea-ice extent in the Pacific sector. We found evidence of a recurring sea-ice protrusion extending to 60 degrees S at 150 degrees W during winter, influenced by the Pacific-Antarctic Ridge (PAR). The PAR also affects the northward deflection of the Antarctic Circumpolar Current front and limits eddy trajectories, resulting in increased sea-ice advance.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Oceanography
Xin Wang, Carlos Moffat, Michael S. Dinniman, John M. Klinck, David A. Sutherland, Borja Aguiar-Gonzalez
Summary: The continental shelf of the West Antarctic Peninsula is characterized by strong alongshore hydrographic gradients influenced by warm Bellingshausen Sea to the south and cold Weddell Sea water to the north. The seasonal and interannual variability in along-shore exchange processes control the spatial structure and variability of glacier retreat and other physical and biochemical factors along the shelf. The wind conditions and hemispheric-scale climate processes play a key role in modulating the amount of cold water flowing into the central West Antarctic Peninsula from Bransfield Strait, highlighting the significance of along-shore exchange in regulating hydrographic properties in the region.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Shigeru Aoki, Tomoki Takahashi, Kaihe Yamazaki, Daisuke Hirano, Kazuya Ono, Kazuya Kusahara, Takeshi Tamura, Guy D. Williams
Summary: Melting ice shelves play a crucial role in the input of freshwater into the ocean and global heat redistribution. In summer 2016/17, the coastal ocean around Antarctica had almost no sea-ice, resulting in higher surface water temperatures. The glacial meltwater fraction in surface water reached a record high, likely due to abnormal ice shelf melting. The excess heat and freshwater delayed the seasonal formation of dense shelf water in early 2017.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Edmo J. D. Campos, Mathias C. van Caspel, Walter Zenk, Eugene G. Morozov, Dmitry I. Frey, Alberto R. Piola, Christopher S. Meinen, Olga T. Sato, Renellys C. Perez, Shenfu Dong
Summary: Research has found that excess heat absorbed from the atmosphere has led to an increase in temperature in the upper layers of the ocean, with signs of warming also appearing in the abyss. Analysis of a new moored temperature time series, along with historical data, confirms the warming of abyssal waters and suggests a possible trend of accelerated warming.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Biology
William S. Y. Wong, Lukas Hauer, Paul A. Cziko, Konrad Meister
Summary: The research finds that the Antarctic scallop Adamussium colbecki possesses a unique micro-ridge structure that allows it to control underwater ice formation, preventing dangerous accumulation and firm attachment of ice. This special structure helps protect the scallops from anchor ice and may be a key trait for their survival in anchor ice zones.
COMMUNICATIONS BIOLOGY
(2022)
Article
Geosciences, Multidisciplinary
G. Finucane, S. Hautala
Summary: The abyssal circulation in the interior portions of the Brazil Basin and northern Argentine Basin were estimated using an overdetermined inverse method conserving neutral surface planetary potential vorticity and salinity. This study found that the Antarctic Bottom Water flows with a northward component through 30 degrees S west of the Rio Grande Rise, but southward transport in the upper part of the AABW across 30 degrees S. The implications of reduced northward transport through the Hunter Channel on the heat budget suggest less diapycnal mixing across the warmer AABW classes.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Qin Wen, Chenyu Zhu, Zixuan Han, Zhengyu Liu, Haijun Yang
Summary: Research suggests that the Tibetan Plateau has a significant impact on Southern Ocean circulation, with its removal potentially enhancing Antarctic bottom water circulation and affecting global climate. This impact is mainly achieved by increasing Rossby wave trains from the tropical Indo-Pacific to the Amundsen-Bellingshausen Sea.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Oceanography
Aditya Narayanan, Sarah T. Gille, Matthew R. Mazloff, Marcel D. du Plessis, K. Murali, Fabien Roquet
Summary: We analyze observational data and model simulation to understand the transformation rates of Circumpolar Deep Water (CDW) and its heat loss to the surface. The study finds that surface buoyancy fluxes transform around 4.4 Sv of surface waters into CDW over East Antarctica, the Weddell and Ross Seas, providing a path for CDW to lose heat. Additionally, around 6.6 Sv of CDW are mixed with surface waters in the Weddell and Ross subpolar gyres. The analysis highlights the importance of subpolar gyres in sheltering Antarctic glaciers.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Multidisciplinary Sciences
Katherine L. Gallagher, Michael S. Dinniman, Heather J. Lynch
Summary: Antarctic krill are important for predators along the West Antarctic Peninsula, and understanding their population connectivity is critical for effective management. This study used a physical ocean model to simulate krill populations across four austral summers, and found that krill north and south of Low Island and the southern Bransfield Strait are isolated from each other due to persistent current features.
SCIENTIFIC REPORTS
(2023)
Article
Oceanography
Stephanie M. Lim, Gert L. van Dijken, Kevin R. Arrigo
Summary: This study investigated the response of Antarctic ice algal habitat to variations in sea ice and other environmental forcings. The research found that the Antarctic has a larger extent and duration of potential ice algal habitat than the Arctic. The bottom ice melt date was identified as the most important factor in explaining the variation in ice algal habitat. The study suggests that Antarctic ice algal habitat may be highly sensitive to future climate changes.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Geosciences, Multidisciplinary
Katherine Hutchinson, Julie Deshayes, Christian Ethe, Clement Rousset, Casimir de Lavergne, Martin Vancoppenolle, Nicolas C. Jourdain, Pierre Mathiot
Summary: By simulating the circulation of Antarctic ice shelves, it was found that a grid resolution of 1 degree is sufficient to produce melt rate patterns and total melt fluxes that agree well with high-resolution models and satellite measurements. Allowing sub-ice shelf circulation reduces salinity biases, produces previously unresolved water masses, and reorganizes shelf circulation to better match observations. This study provides a NEMO configuration for improved representation of Antarctic continental shelf circulation and the precursors of Antarctic Bottom Water (AABW).
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Multidisciplinary Sciences
P. A. Reid, R. A. Massom
Summary: Loss of protective sea-ice buffer in Antarctica has led to increased exposure of the coastal environment to open ocean and waves, which has significant effects on ice-shelf stability, coastal erosion, ice-ocean-atmosphere interactions, and shallow benthic ecosystems. Researchers have introduced a climate and environmental metric called Coastal Exposure Length, which measures the daily changes and variability in the length and occurrence of unprotected coastline in Antarctica. The study found that around 50% of Antarctica's 17,850-km coastline had no sea ice offshore each summer, with variations in exposure levels across regions and seasons. From 1979 to 2020, the annual maximum length of coastal exposure decreased by approximately 30 km per year.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Aidan Starr, Ian R. Hall, Stephen Barker, Thomas Rackow, Xu Zhang, Sidney R. Hemming, H. J. L. van der Lubbe, Gregor Knorr, Melissa A. Berke, Grant R. Bigg, Alejandra Cartagena-Sierra, Francisco J. Jimenez-Espejo, Xun Gong, Jens Gruetzner, Nambiyathodi Lathika, Leah J. LeVay, Rebecca S. Robinson, Martin Ziegler
Summary: Research suggests that during the Pleistocene glaciations over the past 1.5 million years, shifts in Antarctic iceberg melt towards the north resulted in the redistribution of freshwater in the Southern Ocean, potentially connected to the Atlantic meridional overturning circulation, which has significant impacts on global climate and climate change.
