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| Registros recuperados: 86 | |
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| Verdy, A.; Mazloff, M. R.. |
| A Biogeochemical Southern Ocean State Estimate (B-SOSE) is introduced that includes carbon and oxygen fields as well as nutrient cycles. The state estimate is constrained with observations while maintaining closed budgets and obeying dynamical and thermodynamic balances. Observations from profiling floats, shipboard data, underway measurements, and satellites are used for assimilation. The years 2008-2012 are chosen due to the relative abundance of oxygen observations from Argo floats during this time. The skill of the state estimate at fitting the data is assessed. The agreement is best for fields that are constrained with the most observations, such as surface pCO(2) in Drake Passage (44% of the variance captured) and oxygen profiles (over 60% of the... |
| Tipo: Text |
Palavras-chave: Southern Ocean; State estimation; Biogeochemistry. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00662/77394/78995.pdf |
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| Majkut, Joseph D.; Carter, Brendan R.; Froelicher, Thomas L.; Dufour, Carolina O.; Rodgers, Keith B.; Sarmiento, Jorge L.. |
| The Southern Ocean is critically important to the oceanic uptake of anthropogenic CO2. Up to half of the excess CO2 currently in the ocean entered through the Southern Ocean. That uptake helps to maintain the global carbon balance and buffers transient climate change from fossil fuel emissions. However, the future evolution of the uptake is uncertain, because our understanding of the dynamics that govern the Southern Ocean CO2 uptake is incomplete. Sparse observations and incomplete model formulations limit our ability to constrain the monthly and annual uptake, interannual variability and long-term trends. Float-based sampling of ocean biogeochemistry provides an opportunity for transforming our understanding of the Southern Ocean CO2 flux. In this work,... |
| Tipo: Text |
Palavras-chave: Carbon; Southern Ocean; Observational system simulation experiment. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00290/40115/38747.pdf |
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| Convey, P.; Bindschadler, R.; Di Prisco, G.; Fahrbach, E.; Gutt, J.; Hodgson, D. A.; Mayewski, P. A.; Summerhayes, C. P.; Turner, J.; ACCE CONSORTIUM. |
| The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (similar to the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere companion to the Arctic Climate Impact Assessment. |
| Tipo: Text |
Palavras-chave: Antarctica; Biology; Environmental change; Geology; Glaciology; Southern Ocean. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00292/40357/82998.pdf |
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| Tournadre, Jean; Bouhier, Nicolas; Girard-ardhuin, Fanny; Remy, F.. |
| Basal melting of floating ice shelves and iceberg calving constitute the two almost equal paths of freshwater flux between the Antarctic ice cap and the Southern Ocean. The largest icebergs (>100 km2) transport most of the ice volume but their basal melting is small compared to their breaking into smaller icebergs that constitute thus the major vector of freshwater. The archives of nine altimeters have been processed to create a database of small icebergs (<8 km2) within open water containing the positions, sizes, and volumes spanning the 1992–2014 period. The intercalibrated monthly ice volumes from the different altimeters have been merged in a homogeneous 23 year climatology. The iceberg size distribution, covering the 0.1–10,000 km2 range,... |
| Tipo: Text |
Palavras-chave: Iceberg; Altimetry; Southern Ocean. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00307/41863/41114.pdf |
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| Pierrat, Benjamin; Saucede, Thomas; Festeau, Main; David, Bruno. |
| This database includes spatial data of Antarctic, Sub-Antarctic and cold temperate echinoid distribution (Echinodermata: Echinoidea) collected during many oceanographic campaigns led in the Southern Hemisphere from 1872 to 2010. The dataset lists occurrence data of echinoid distribution south of 35 degrees S latitude, together with information on taxonomy (from species to genus level), sampling sources (cruise ID, sampling dates, ship names) and sampling sites (geographic coordinates and depth). Echinoid occurrence data were compiled from the Antarctic Echinoid Database (David et al. 2005a), which integrates records from oceanographic cruises led in the Southern Ocean until 2003. This database has been upgraded to take into account data from oceanographic... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Echinoids; Antarctic species; Sub-Antarctic species; Cold temperate species. |
| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00296/40763/39773.pdf |
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| Lo Monaco, C; Metzl, N; Poisson, A; Brunet, C; Schauer, B. |
| The Southern Ocean, where various water masses are formed ( mode, intermediate, deep, and bottom waters), has a high potential to absorb anthropogenic CO(2) ( C ant). However, most data-based and model estimates indicate low C(ant) inventories south of 50 degrees S. In order to investigate this paradox, the distribution of C(ant) is estimated between South Africa and Antarctica ( World Ocean Circulation Experiment ( WOCE) line I6) based on a back-calculation technique previously used in the North Atlantic ( Kortzinger et al., 1998) and adapted here for application in the Southern Ocean. At midlatitudes (30 degrees-50 degrees S), formation and spreading of mode and intermediate waters results in a deep penetration of C(ant) ( down to 2000 m). South of 50... |
| Tipo: Text |
Palavras-chave: Anthropogenic CO2; Southern Ocean; WOCE. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00233/34409/32823.pdf |
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| Olsen, Are. |
| While the number of surface ocean CO2 partial pressure (pCO(2)) measurements has soared the recent decades, the Southern Ocean remains undersampled. Williams et al. (2017) now present pCO(2) estimates based on data from pH-sensor equipped Bio-Argo floats, which have been measuring in the Southern Ocean since 2014. The authors demonstrate the utility of these data for understanding the carbon cycle in this region, which has a large influence on the distribution of CO2 between the ocean and atmosphere. Biogeochemical sensors deployed on autonomous platforms hold the potential to shape our view of the ocean carbon cycle in the coming decades. |
| Tipo: Text |
Palavras-chave: Ocean carbon; Southern Ocean; Autonomous observations. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00661/77325/78792.pdf |
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| Fagel, N; Dehairs, F; Andre, L; Bareille, G; Monnin, C. |
| We present excess Ba (Baxs) data (i.e., total Ba corrected for lithogenic Ba) for surface sediments from a north-south transect between the Polar Front Zone and the northern Weddell Gyre in the Atlantic sector and between the Polar Front Zone and the Antarctic continent in the Indian sector. Focus is on two different processes that affect excess Ba accumulation in the sediments: sediment redistribution and excess Ba dissolution. The effect of these processes needs to be corrected for in order to convert accumulation rate into vertical rain rate, the flux component that can be linked to export production. In the Southern Ocean a major process affecting Ba accumulation rate is sediment focusing, which is corrected for using excess (230)Th. This correction,... |
| Tipo: Text |
Palavras-chave: Excess Ba; Sediment; Southern Ocean; Export production. |
| Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/00223/33392/31868.pdf |
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| Johnson, Kenneth S.; Plant, Joshua N.; Coletti, Luke J.; Jannasch, Hans W.; Sakamoto, Carole M.; Riser, Stephen C.; Swift, Dana D.; Williams, Nancy L.; Boss, Emmanuel; Haentjens, Nils; Talley, Lynne D.; Sarmiento, Jorge L.. |
| The Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) program has begun deploying a large array of biogeochemical sensors on profiling floats in the Southern Ocean. As of February 2016, 86 floats have been deployed. Here the focus is on 56 floats with quality-controlled and adjusted data that have been in the water at least 6 months. The floats carry oxygen, nitrate, pH, chlorophyll fluorescence, and optical backscatter sensors. The raw data generated by these sensors can suffer from inaccurate initial calibrations and from sensor drift over time. Procedures to correct the data are defined. The initial accuracy of the adjusted concentrations is assessed by comparing the corrected data to laboratory measurements made on samples collected... |
| Tipo: Text |
Palavras-chave: Profiling floats; Oxygen sensors; PH sensors; Nitrate sensors; Bio-optical sensors; Southern Ocean. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00662/77398/78993.pdf |
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| Cubillos, J. C.; Wright, S. W.; Nash, G.; De Salas, M. F.; Griffiths, B.; Tilbrook, B.; Poisson, A.; Hallegraeff, G. M.. |
| We conducted a scanning electron microscopic survey of morphological variations in the calcareous nanoplankton species Emiliania huxleyi in Southern Ocean surface water samples collected along a transect from 43 to 64 degrees S and 141 to 145 degrees E during November 2001, October to February 2002/2003, 2003/2004, 2004/2005 and 2005/2006. The results were compared with historical data from a similar transect occupied in December to January 1983/1984 and January to February 1994 and 1995. While E. huxleyi was absent or extremely sparse (0.1 to 1 cells ml(-1)) south of 60 degrees S in 1983/1984 and 1994/1995, this species was consistently present at about 100 cells ml(-1) between 60 and 65 degrees S during 2002 to 2006. The extended geographic range and/or... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Emiliania huxleyi; Calcite saturation state; Ocean acidification. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00236/34735/33191.pdf |
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| Henley, Sian F.; Cavan, Emma L.; Fawcett, Sarah E.; Kerr, Rodrigo; Monteiro, Thiago; Sherrell, Robert M.; Bowie, Andrew R.; Boyd, Philip W.; Barnes, David K. A.; Schloss, Irene R.; Marshall, Tanya; Flynn, Raquel; Smith, Shantelle. |
| The Southern Ocean plays a critical role in regulating global climate as a major sink for atmospheric carbon dioxide (CO2), and in global ocean biogeochemistry by supplying nutrients to the global thermocline, thereby influencing global primary production and carbon export. Biogeochemical processes within the Southern Ocean regulate regional primary production and biological carbon uptake, primarily through iron supply, and support ecosystem functioning over a range of spatial and temporal scales. Here, we assimilate existing knowledge and present new data to examine the biogeochemical cycles of iron, carbon and major nutrients, their key drivers and their responses to, and roles in, contemporary climate and environmental change. Projected increases in... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Biogeochemistry; Primary production; Iron; Nutrients; Carbon; Ecosystem; Ocean acidification. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00676/78831/81113.pdf |
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| Hemery, Lenaig G.; Ameziane, Nadia; Eleaume, Marc. |
| This circumpolar dataset of the comatulid (Echinodermata: Crinoidea) Promachocrinus kerguelensis (Carpenter, 1888) from the Southern Ocean, documents biodiversity associated with the specimens sequenced in Hemery et al. (2012). The aim of Hemery et al. (2012) paper was to use phylogeographic and phylogenetic tools to assess the genetic diversity, demographic history and evolutionary relationships of this very common and abundant comatulid, in the context of the glacial history of the Antarctic and Sub-Antarctic shelves (Thatje et al. 2005, 2008). Over one thousand three hundred specimens (1307) used in this study were collected during seventeen cruises from 1996 to 2010, in eight regions of the Southern Ocean: Kerguelen Plateau, Davis Sea, Dumont d'Urville... |
| Tipo: Text |
Palavras-chave: Antarctica; Crinoidea; Cytochrome Oxydase subunit I; Echinodermata; Phylogeography; Promachocrinus; Southern Ocean; Sub-Antarctic. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00296/40758/39749.pdf |
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| Sokolov, Serguei; Rintoul, Stephen R.. |
| High resolution hydrographic sections and maps of the gradient of sea surface height (SSH) reveal that the Antarctic Circumpolar Current (ACC) consists of multiple jets or frontal filaments. Here we use a 15 year time series of SSH observations to determine the circumpolar structure and distribution of the ACC fronts. The jets are consistently aligned with particular streamlines along the entire circumpolar path, confirming and extending the results of an earlier study restricted to the region south of Australia. The intensity of the fronts (as measured by the cross-front gradient of SSH) varies along the fronts and the individual branches merge and diverge, often in response to interactions with bathymetry. Maps of absolute velocity at 1000 m depth... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Antarctic Circumpolar Current. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00253/36387/34931.pdf |
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| Le Paih, Nicolas; Hattermann, Tore; Boebel, Olaf; Kanzow, Torsten; Lüpkes, Christof; Rohardt, Gerd; Strass, Volker; Herbette, Steven. |
| The Weddell Sea is of global importance in the formation of dense bottom waters associated with sea‐ice formation and ocean‐ice sheet interaction occurring on the shelf areas. In this context, the Weddell Sea boundary current system (BCS) presents a major conduit for transporting relatively warm water to the Weddell Sea ice shelves and for exporting {some modified form of Wedell Sea deep and bottom waters into the open ocean. This study investigates the downstream evolution of the structure and the seasonality of the BCS along the Weddell Sea continental slope, combining ocean data collected for the past two decades at three study locations. The interannual‐mean geostrophic flow, which follows planetary potential vorticity contours, shifts from being... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Weddell Sea; Antarctic slope current; Surface stress; Flow strength; Teleconnection. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00652/76398/77436.pdf |
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| Lasbleiz, Marine; Leblanc, Karine; Armand, Leanne K.; Christaki, Urania; Georges, Clement; Obernosterer, Ingrid; Queguiner, Bernard. |
| In the naturally iron-fertilized surface waters of the northern Kerguelen Plateau region, the early spring diatom community composition and contribution to plankton carbon biomass were investigated and compared with the High Nutrient Low Chlorophyll (HNLC) surrounding waters. The large iron-induced blooms were dominated by small diatom species belonging to the genera Chaetoceros (Hyalochaete) and Thalassiosira, which rapidly responded to the onset of favorable light-conditions in the meander of the Polar Front. In comparison, the iron-limited HNLC area was typically characterized by autotrophic nanoeukaryote-dominated communities and by larger and more heavily silicified diatom species (e.g. Fragilariopsis spp.). Our results support the hypothesis that... |
| Tipo: Text |
Palavras-chave: Diatoms; Carbon biomass; Plankton community structure; Natural iron fertilization; Southern Ocean. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00347/45850/45512.pdf |
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| Abarnou, Alain; Robineau, Daniel; Michel, Pierre. |
| Top predators like marine mammals have been intensively used for monitoring the contamination of the marine environment, particularly in industrialized coastal areas of the Northern Atlantic Ocean. Such data concerning contamination in the Southern hemisphere are very scarce. Samples were taken in the fatty protuberance of the forehead (melon) from eleven Commerson's dolphins (Cephalorhynchus commersonii, Lacépède, 1804) caught in the coastal waters of the Kerguelen Islands (Southern Indian Ocean). They were analyzed for DDT, PCB and HCB, using capillary gaz chromatography. The levels of contamination [DDT= 1 150 ± 650, PCB = 1 150 ± 770, HCB=500±300ng/g of extracted matter (lipids)] are between ten and a hundred times Jess than those found in similar... |
| Tipo: Text |
Palavras-chave: Organochlorés; Mammifères marins; Océan austral; Iles Kerguelen; Organochlorines; Marine mammals; Southern Ocean; Kerguelen Islands. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00111/22273/19948.pdf |
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| Cheize, Marie; Planquette, H.f.; Fitzsimmons, J.n.; Pelleter, Ewan; Sherrell, R.m.; Lambert, Christophe; Bucciarelli, E.; Sarthou, G.; Le Goff, Marion; Liorzou, Celine; Chéron, Sandrine; Viollier, E.; Gayet, Nicolas. |
| A number of trace metals play essential roles in marine ecosystem structure and biological productivity. Until recently, it has been argued that phytoplankton access primarily dissolved iron, while particulate iron was considered a refractory material with little use biologically and limited interaction with the dissolved pool. In order to assess the transfer mechanisms between sediment-sourced particulate trace metals and the dissolved pool, we conducted a 14-month incubation that reacted resuspended sediments with natural seawater, both originating from the Kerguelen area (KEOPS cruises; Southern Ocean), in the dark, and at concentrations replicating natural conditions. Three types of sediments were investigated (named BioSi, BioSi + Ca, and Basalt),... |
| Tipo: Text |
Palavras-chave: Suspended particle dissolution; Sediment; Iron; Manganese; Biogenic silica; Southern Ocean; Kerguelen. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00460/57197/59166.pdf |
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| Registros recuperados: 86 | |
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