scholarly journals Long-term iceshelf-covered meiobenthic communities of the Antarctic continental shelf resemble those of the deep sea

2014 ◽  
Vol 45 (4) ◽  
pp. 743-762 ◽  
Author(s):  
Armin Rose ◽  
Jeroen Ingels ◽  
Maarten Raes ◽  
Ann Vanreusel ◽  
Pedro Martínez Arbizu
Keyword(s):  
Continental Shelf ◽  
Deep Sea ◽  
Antarctic Continental Shelf ◽  
The Antarctic

scholarly journals Multidecadal warming of Antarctic waters

Science ◽  
2014 ◽  
Vol 346 (6214) ◽  
pp. 1227-1231 ◽  
Author(s):  
Sunke Schmidtko ◽  
Karen J. Heywood ◽  
Andrew F. Thompson ◽  
Shigeru Aoki
Keyword(s):  
Continental Shelf ◽  
Large Scale ◽  
Bottom Water ◽  
Heat Content ◽  
Ice Shelf ◽  
Antarctic Continental Shelf ◽  
Antarctic Waters ◽  
Core Depth ◽  
The Antarctic

Decadal trends in the properties of seawater adjacent to Antarctica are poorly known, and the mechanisms responsible for such changes are uncertain. Antarctic ice sheet mass loss is largely driven by ice shelf basal melt, which is influenced by ocean-ice interactions and has been correlated with Antarctic Continental Shelf Bottom Water (ASBW) temperature. We document the spatial distribution of long-term large-scale trends in temperature, salinity, and core depth over the Antarctic continental shelf and slope. Warming at the seabed in the Bellingshausen and Amundsen seas is linked to increased heat content and to a shoaling of the mid-depth temperature maximum over the continental slope, allowing warmer, saltier water greater access to the shelf in recent years. Regions of ASBW warming are those exhibiting increased ice shelf melt.

A new species of Regabellator Siebenaller & Hessler, 1981 (Isopoda, Asellota, Nannoniscidae) from the Amundsen Sea shelf (Southern Ocean)

Crustaceana ◽  
2015 ◽  
Vol 88 (4) ◽  
pp. 405-421 ◽  
Author(s):  
S. S. M. Kaiser
Keyword(s):  
New Species ◽  
Continental Shelf ◽  
Deep Sea ◽  
First Record ◽  
Amundsen Sea ◽  
The North ◽  
Antarctic Continental Shelf ◽  
The Antarctic ◽  
North And South ◽  
A New Species

Based on benthic material collected during the BIOPEARL (Biodiversity, Phylogeny, Evolution and Adaptive Radiation of Life in Antarctica) II expedition on board RRS “James Clark Ross” a new nannoniscid species,Regabellator brixorumsp. n., is described from the Pine Island Bay continental shelf, western Amundsen Sea (Antarctica). The new species most closely resemblesRegabellator armatus(Hansen, 1916) but can be distinguished from this species by possessing ventral spines on pereonites 1-4, the shape of the cephalothorax anterior margin and the length of the pereonite 7 ventral spine. The genusRegabellatorhas been previously recorded from the North and South-eastern Atlantic and here exclusively from the deep sea (1946 m and below). The new species represents the first record of the genusRegabellatorfrom the Antarctic continental shelf and thus greatly extends hitherto known latitudinal and bathymetric ranges for this genus.

scholarly journals Probing the depths

2004 ◽  
Vol 16 (1) ◽  
pp. 1-4 ◽  
Author(s):  
ANDREW CLARKE
Keyword(s):  
Continental Shelf ◽  
Deep Sea ◽  
Marine Invertebrate ◽  
Antarctic Sea Ice ◽  
Antarctic Continental Shelf ◽  
Marine Diversity ◽  
History Of ◽  
Total Fauna ◽  
The Tropics ◽  
The Antarctic

When scientists from HMS Challenger dredged animals from over 5km depth, they finally laid to rest the azoic hypothesis of Edward Forbes, that life could not exist in cold dark depths of the ocean, and thereby opened the doors to true deep-sea biology. The past decade has witnessed a further sea change in our view of marine diversity, if I may be permitted the pun, a change driven to a large extent by improved knowledge from Antarctica. For many years we viewed the tropics as the engines of diversity; species arose in warm clear seas, especially those associated with coral reefs, and spread slowly to populate the harsher high latitudes. Early studies of the isopod fauna had also suggested that at least some organisms living on the continental shelf of Antarctica may have originated in the deep sea. After a period of intense work, much of it under the auspices of the SCAR EASIZ (Ecology of the Antarctic Sea Ice Zone) and more recently the EVOLANTA(Evolution in Antarctica) programmes, we can now modify both hypotheses, with powerful implications for our understanding of global marine diversity. The marine invertebrate fauna of the Antarctic continental shelf is now better described than might be thought, and the total fauna may well exceed 17000 taxa. Interestingly, there are very few places in the world with comparable data, but we can say that the fauna has had a long history of evolution in situ and is not simply a last refuge for taxa that originated elsewhere.

Pathways and timescales of connectivity around the Antarctic continental shelf 

2021 ◽  
Author(s):  
Hannah Dawson ◽  
Adele Morrison ◽  
Veronica Tamsitt ◽  
Matthew England
Keyword(s):  
Continental Shelf ◽  
Ross Sea ◽  
Coastal Current ◽  
West Antarctica ◽  
Source Regions ◽  
Freshwater Forcing ◽  
Antarctic Continental Shelf ◽  
Antarctic Continent ◽  
Antarctic Slope Current ◽  
The Antarctic

<p><span xml:lang="EN-US" data-contrast="auto"><span>The Antarctic margin is surrounded by two westward flowing currents: the Antarctic Slope Current and the Antarctic Coastal Current. The former influences key processes near the Antarctic margin by regulating the flow of heat and nutrients onto and off the continental shelf, while together they </span></span><span xml:lang="EN-US" data-contrast="auto"><span>advect</span></span><span xml:lang="EN-US" data-contrast="auto"><span> nutrients, biological organisms, and temperature and salinity anomalies around the coastline, providing a connective link between different shelf regions. However, the extent to which these currents transport water from one sector of the continental shelf to another, and the timescales over which this occurs, remain poorly understood. Concern that crucial water formation sites around the Antarctic coastline could respond to non-local freshwater forcing </span></span><span><span xml:lang="EN-US" data-contrast="auto"><span>from ice shel</span></span></span><span><span xml:lang="EN-US" data-contrast="auto"><span>f meltwater</span></span></span> <span xml:lang="EN-US" data-contrast="auto"><span>motivates a more thorough understanding of zonal connectivity around Antarctica. In this study, we use daily velocity fields from a global high-resolution ocean-sea ice model, combined with the <span>Lagrangian</span> tracking software Parcels, to investigate the pathways and timescales connecting different regions of the Antarctic continental shelf<span> with a view to understanding</span><span> the timescales of meltwater transport around the continent</span>. Virtual particles are released over the continental shelf, poleward of the 1000 <span>metre</span> isobath, and are tracked for 20 years. Our results show a strong seasonal cycle connecting different sectors of the Antarctic continent, with more particles arriving further downstream during winter than during summer months. Strong advective links exist between West Antarctica and the Ross Sea while shelf geometry in some other regions acts as barriers to transport. We also highlight the varying importance of the Antarctic Slope Current and Antarctic Coastal Current in connecting different sectors of the coastline. Our results help to improve our understanding of circum-Antarctic connectivity <span>and the timescales </span><span>of meltwater transport from source regions to downstream </span><span>shelf locations. </span><span>Further</span><span>more, t</span><span>he timescales and pathways we </span><span>present </span><span>p</span>rovide a baseline from which to assess long-term changes in Antarctic coastal circulation due to local and remote forcing.<br></span></span></p>

scholarly journals Toxic anthropogenic signature in Antarctic continental shelf and deep sea sediments

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Enrique Isla ◽  
Elisabet Pérez-Albaladejo ◽  
Cinta Porte
Keyword(s):  
Continental Shelf ◽  
Deep Sea ◽  
Antarctic Continental Shelf ◽  
Deep Sea Sediments

scholarly journals Explicit and parametrised representation of under ice shelf seas in a z<sup>*</sup> coordinate ocean model

2017 ◽  
Author(s):  
Pierre Mathiot ◽  
Adrian Jenkins ◽  
Christopher Harris ◽  
Gurvan Madec
Keyword(s):  
Sea Ice ◽  
Continental Shelf ◽  
Weddell Sea ◽  
Depth Range ◽  
Ice Shelf ◽  
Ice Shelves ◽  
Antarctic Continental Shelf ◽  
Shelf Seas ◽  
Ocean Properties ◽  
The Antarctic

Abstract. Ice shelf/ocean interactions are a major source of fresh water on the Antarctic continental shelf and have a strong impact on ocean properties, ocean circulation and sea ice. However, climate models based on the ocean/sea ice model NEMO currently do not include these interactions in any detail. The capability of explicitly simulating the circulation beneath ice shelves is introduced in the non-linear free surface model NEMO. Its implementation into the NEMO framework and its assessment in an idealised and realistic circum-Antarctic configuration is described in this study. Compared with the current prescription of ice shelf melting (i.e. at the surface) inclusion of open sub-ice-shelf leads to a decrease sea ice thickness along the coast, a weakening of the ocean stratification on the shelf, a decrease in salinity of HSSW on the Ross and Weddell Sea shelves and an increase in the strength of the gyres that circulate within the over-deepened basins on the West Antarctic continental shelf. Mimicking the under ice shelf seas overturning circulation by introducing the meltwater over the depth range of the ice shelf base, rather than at the surface is also tested. It yields similar improvements in the simulated ocean properties and circulation over the Antarctic continental shelf than the explicit ice shelf cavity representation. With the ice shelf cavities opened, the widely-used “3 equations” ice shelf melting formulation enables an interactive computation of melting that has been assessed. Comparison with observational estimates of ice shelf melting indicates realistic results for most ice shelves. However, melting rates for Amery, Getz and George VI ice shelves are considerably overestimated.

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