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| Registros recuperados: 15 | |
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| Yunda-guarin, Gustavo; Brown, Thomas A.; Michel, Loic; Saint-béat, Blanche; Amiraux, Rémi; Nozais, Christian; Archambault, Philippe. |
| Benthic organisms depend primarily on seasonal pulses of organic matter from primary producers. In the Arctic, declines in sea ice due to warming climate could lead to changes in this food supply with as yet unknown effects on benthic trophic dynamics. Benthic consumer diets and food web structure were studied in a seasonally ice-covered region of Baffin Bay during spring 2016 at stations ranging in depth from 199 to 2,111 m. We used a novel combination of highly branched isoprenoid (HBI) lipid biomarkers and stable isotope ratios (δ13C, δ15N) to better understand the relationship between the availability of carbon sources in spring on the seafloor and their assimilation and transfer within the benthic food web. Organic carbon from sea ice (sympagic carbon... |
| Tipo: Text |
Palavras-chave: Benthic food webs; Trophic markers; Sea-ice algae; Climate change; HBIs; Stable isotopes; Baffin Bay; Arctic Ocean. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00665/77749/79870.pdf |
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| Thomson, Jim; Fan, Yalin; Stammerjohn, Sharon; Stopa, Justin; Erick Rogers, W.; Girard-ardhuin, Fanny; Ardhuin, Fabrice; Shen, Hayley; Perrie, Will; Shen, Hui; Ackley, Steve; Babanin, Alex; Liu, Qingxiang; Guest, Peter; Maksym, Ted; Wadhams, Peter; Fairall, Chris; Persson, Ola; Doble, Martin; Graber, Hans; Lund, Bjoern; Squire, Vernon; Gemmrich, Johannes; Lehner, Susanne; Holt, Benjamin; Meylan, Mike; Brozena, John; Bidlot, Jean-raymond. |
| The sea state of the Beaufort and Chukchi seas is controlled by the wind forcing and the amount of ice-free water available to generate surface waves. Clear trends in the annual duration of the open water season and in the extent of the seasonal sea ice minimum suggest that the sea state should be increasing, independent of changes in the wind forcing. Wave model hindcasts from four selected years spanning recent conditions are consistent with this expectation. In particular, larger waves are more common in years with less summer sea ice and/or a longer open water season, and peak wave periods are generally longer. The increase in wave energy may affect both the coastal zones and the remaining summer ice pack, as well as delay the autumn ice-edge advance.... |
| Tipo: Text |
Palavras-chave: Sea ice; Arctic Ocean; Ocean surface waves. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00345/45590/45202.pdf |
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| Lique, Camille; Treguier, Anne-marie; Scheinert, Markus; Penduff, Thierry. |
| We investigate some aspects of the variability of the Arctic freshwater content during the 1965-2002 period using the DRAKKAR eddy admitting global ocean/sea-ice model (12 km resolution in the Arctic). A comparison with recent mooring sections shows that the model realistically represents the major advective exchanges with the Arctic basin, through Bering, Fram and Davis Straits, and the Barents Sea. This allows the separate contributions of the inflows and outflows across each section to be quantified. In the model, the Arctic freshwater content variability is explained by the sea-ice flux at Fram and the combined variations of ocean freshwater inflow (at Bering) and outflow (at Fram and Davis). At all routes, except trough Fram Strait, the freshwater... |
| Tipo: Text |
Palavras-chave: Fram Strait; Davis Strait; Freshwater flux; Freshwater budget; Arctic Ocean. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6713.pdf |
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| Thingstad, T Frede; Browman, Howard. |
| In linear food chains, resource and predator control produce positive and negative correlations, respectively, between biomass at adjacent trophic levels. These simple relationships become more complex in food webs that contain alternative food chains of unequal lengths. We have used a “minimum” model for the microbial part of the pelagic food web that has three such food chains connecting free mineral nutrients to copepods: via diatoms, autotrophic flagellates, and heterotrophic bacteria. Trophic cascades from copepods strongly modulates the balance between the three pathways and, therefore, the functionality of the microbial food web in services such as food production for higher trophic levels, DOM degradation, and ocean carbon sequestration. The result... |
| Tipo: Text |
Palavras-chave: Arctic Ocean; Bottom-up; Mediterranean Sea; Microbial food web; Nansen Legacy; Top down; Trophic cascades. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00627/73958/73312.pdf |
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| Carr, Magda; Sutherland, Peter; Haase, Andrea; Evers, Karl‐ulrich; Fer, Ilker; Jensen, Atle; Kalisch, Henrik; Berntsen, Jarle; Părău, Emilian; Thiem, Øyvind; Davies, Peter. |
| Internal solitary waves (ISWs) propagating in a stably stratified two-layer fluid in which the upper boundary condition changes from open water to ice are studied for grease, level, and nilas ice. The ISW-induced current at the surface is capable of transporting the ice in the horizontal direction. In the level ice case, the transport speed of, relatively long ice floes, nondimensionalized by the wave speed is linearly dependent on the length of the ice floe nondimensionalized by the wave length. Measures of turbulent kinetic energy dissipation under the ice are comparable to those at the wave density interface. Moreover, in cases where the ice floe protrudes into the pycnocline, interaction with the ice edge can cause the ISW to break or even be destroyed... |
| Tipo: Text |
Palavras-chave: Internal solitary waves; Sea ice; Arctic Ocean. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00593/70532/68677.pdf |
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| Lique, Camille. |
| While perhaps the most obvious, ice retreat is just one aspect of a changing Arctic system. The Arctic Ocean is also undergoing unprecedented modifications, that mostly affect its heat and freshwater budgets. As the signal of Arctic change is expected to have its major climatic impact by reaching south the subarctic seas, on either side of Greenland, to modulate the Atlantic thermohaline circulation, the objective of this thesis is to investigate the variability of the exports of volume, heat, freshwater and sea-ice from the Arctic Ocean to the North Atlantic. First, a realistic simulation from 1958 to 2002 run with a global ocean/sea-ice model is used to investigate some aspects of the variability of the Arctic freshwater budget, trying to understand... |
| Tipo: Text |
Palavras-chave: Océan Arctique; Bilan d'eau douce; Flux d'eau douce; Glace de mer; Modèle numérique - Analyse Lagrangienne - Forçages atmosphériques; Arctic Ocean; Freshwater budget; Freshwater flux; Sea ice; Numerical model; Lagrangian analysis; Atmospheric forcing. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00015/12597/9474.pdf |
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| Ilicak, Mehmet; Drange, Helge; Wang, Qiang; Gerdes, Rudiger; Aksenov, Yevgeny; Bailey, David; Bentsen, Mats; Biastoch, Arne; Bozec, Alexandra; Boening, Claus; Cassou, Christophe; Chassignet, Eric; Coward, Andrew C.; Curry, Beth; Danabasoglu, Gokhan; Danilov, Sergey; Fernandez, Elodie; Fogli, Pier Giuseppe; Fujii, Yosuke; Griffies, Stephen M.; Iovino, Doroteaciro; Jahn, Alexandra; Jung, Thomas; Large, William G.; Lee, Craig; Lique, Camille; Lu, Jianhua; Masina, Simona; Nurser, A. J. George; Roth, Christina; Salas Y Melia, David; Samuels, Bonita L.; Spence, Paul; Tsujino, Hiroyuki; Valcke, Sophie; Voldoire, Aurore; Wang, Xuezhu; Yeager, Steve G.. |
| In this paper we compare the simulated Arctic Ocean in 15 global ocean–sea ice models in the framework of the Coordinated Ocean-ice Reference Experiments, phase II (CORE-II). Most of these models are the ocean and sea-ice components of the coupled climate models used in the Coupled Model Intercomparison Project Phase 5 (CMIP5) experiments. We mainly focus on the hydrography of the Arctic interior, the state of Atlantic Water layer and heat and volume transports at the gateways of the Davis Strait, the Bering Strait, the Fram Strait and the Barents Sea Opening. We found that there is a large spread in temperature in the Arctic Ocean between the models, and generally large differences compared to the observed temperature at intermediate depths. Warm bias... |
| Tipo: Text |
Palavras-chave: Arctic Ocean; Atlantic Water; St. Anna Trough; Density currents; CORE-II atmospheric forcing. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00317/42864/42295.pdf |
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| Oziel, L.; Massicotte, P.; Randelhoff, A.; Ferland, J.; Vladoiu, A.; Lacour, L.; Galindo, V; Lambert-girard, S.; Dumont, D.; Cuypers, Y.; Bouruet-aubertot, P.; Mundy, C-j; Ehn, J.; Becu, G.; Marec, Claudie; Forget, M-h; Garcia, N.; Coupel, P.; Raimbault, P.; Houssais, M-n; Babin, M.. |
| Arctic sea ice is experiencing a shorter growth season and an earlier ice melt onset. The significance of spring microalgal blooms taking place prior to sea ice breakup is the subject of ongoing scientific debate. During the Green Edge project, unique time-series data were collected during two field campaigns held in spring 2015 and 2016, which documented for the first time the concomitant temporal evolution of the sea ice algal and phytoplankton blooms in and beneath the landfast sea ice in western Baffin Bay. Sea ice algal and phytoplankton blooms were negatively correlated and respectively reached 26 (6) and 152 (182) mg of chlorophyll a per m(2) in 2015 (2016). Here, we describe and compare the seasonal evolutions of a wide variety of physical... |
| Tipo: Text |
Palavras-chave: Under-ice bloom; Phytoplankton and sea ice algae; Arctic Ocean; Baffin Bay; Environmental conditions; Light and mixing. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00513/62487/66800.pdf |
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| Schneider, A.; Panieri, G.; Lepland, A.; Consolaro, C.; Cremiere, A.; Forwick, M.; Johnson, J. E.; Plaza-faverola, A.; Sauer, S.; Knies, J.. |
| Multiple proxies in the geological record offshore NW Svalbard track shallow subseafloor diagenesis and seafloor methane seepage during the Last Glacial Maximum (LGM) extent and the disintegration of the Svalbard Barents Sea Ice Sheet (SBIS). Vestnesa Ridge, located at 79°N and in 1200 m water depth, is one of the northernmost known active methane seep sites and is characterised by a subseafloor fluid flow system, numerous seafloor pockmarks and gas flares in the water column. In this study, we develop a Late Pleistocene and Holocene stratigraphic framework, use stable oxygen and carbon isotope signatures (δ18O, δ13C) of benthic and planktic foraminifera, the mineralogical and carbon isotope composition of methane-derived authigenic carbonate (MDAC) and... |
| Tipo: Text |
Palavras-chave: Micropaleontology; Foraminifers; Stable isotopes; Methane seepage; Authigenic carbonate; Holocene; Pleistocene; Paleogeography; Deglaciation; Arctic Ocean. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00445/55652/60554.pdf |
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| Dessandier, Pierre-antoine; Borrelli, Chiara; Kalenitchenko, Dimitri; Panieri, Giuliana. |
| Benthic foraminifera have been widely used as proxy for paleo-methane emissions, mainly based on their stable isotopic signature. In cold seeps, the ecology of these organisms remains uncertain, in particular their ability to thrive during active phases of seepage. In this study, we evaluate the benthic foraminiferal response to methane seepage in Arctic sediments. We do so by examining living and dead benthic foraminiferal assemblages (>63 mu m) of 11 push cores collected in two of the most active pockmarks (Lunde and Lomvi) along Vestnesa Ridge, offshore western Svalbard. Benthic foraminiferal assemblages are interpreted in the context of sediment geochemistry, seafloor images, and pore water analyses, which are used to characterize the different... |
| Tipo: Text |
Palavras-chave: Benthic foraminiferal assemblages; Methane advection; Methane diffusion; Arctic Ocean; Microbial mats. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00667/77894/80079.pdf |
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| Wang, Qiang; Ilicak, Mehmet; Gerdes, Ruediger; Drange, Helge; Aksenov, Yevgeny; Bailey, David A.; Bentsen, Mats; Biastoch, Arne; Bozec, Alexandra; Boening, Claus; Cassou, Christophe; Chassignet, Eric; Coward, Andrew C.; Curry, Beth; Danabasoglu, Gokhan; Danilov, Sergey; Fernandez, Elodie; Fogli, Pier Giuseppe; Fujii, Yosuke; Griffies, Stephen M.; Iovino, Doroteaciro; Jahn, Alexandra; Jung, Thomas; Large, William G.; Lee, Craig; Lique, Camille; Lu, Jianhua; Masina, Simona; Nurser, A. J. George; Rabe, Benjamin; Roth, Christina; Salas Y Melia, David; Samuels, Bonita L.; Spence, Paul; Tsujino, Hiroyuki; Valcke, Sophie; Voldoire, Aurore; Wang, Xuezhu; Yeager, Steve G.. |
| The Arctic Ocean simulated in 14 global ocean-sea ice models in the framework of the Coordinated Ocean-ice Reference Experiments, phase II (CORE-II) is analyzed in this study. The focus is on the Arctic liquid freshwater (FW) sources and freshwater content (FWC). The models agree on the interannual variability of liquid FW transport at the gateways where the ocean volume transport determines the FW transport variability. The variation of liquid FWC is induced by both the surface FW flux (associated with sea ice production) and lateral liquid FW transport, which are in phase when averaged on decadal time scales. The liquid FWC shows an increase starting from the mid-1990s, caused by the reduction of both sea ice formation and liquid FW export, with the... |
| Tipo: Text |
Palavras-chave: Arctic Ocean; Freshwater; Sea ice; CORE II atmospheric forcing. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00313/42463/41835.pdf |
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| Oleszczuk, Barbara; Michaud, Emma; Morata, Nathalie; Renaud, Paul E.; Kędra, Monika. |
| The aim of this study was to assess bioturbation rates in relation to macrozoobenthos and environmental variables in the Svalbard fjords, Barents Sea and Nansen Basin during spring to summer transition. The results showed differences in benthic community structure across sampled area in relation to sediment type and phytopigment content. Fjords, Barents Sea and the shallow parts of Nansen Basin (<400 m) were characterized by high functional groups diversity, and by biodiffusive and non-local rates ranging from 0.05 to 1.75 cm−2 y−1 and from 0.2 to 3.2 y−1, respectively. The deeper parts of Nansen Basin, dominated by conveyors species, showed only non-local transport rates (0.1–1 y−1). Both coefficients intensity varied with benthic biomass. Non-local... |
| Tipo: Text |
Palavras-chave: Non-local transport; Biodiffusive transport; Macrozoobenthos; Spring season; Sea ice cover; Arctic Ocean. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00502/61329/64901.pdf |
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| Muilwijk, Morven; Ilicak, Mehmet; Cornish, Sam B.; Danilov, Sergey; Gelderloos, Renske; Gerdes, Rüdiger; Haid, Verena; Haine, Thomas W.n.; Johnson, Helen L.; Kostov, Yavor; Kovács, Tamás; Lique, Camille; Marson, Juliana M.; Myers, Paul G.; Scott, Jon; Smedsrud, Lars H.; Talandier, Claude; Wang, Qiang. |
| Multi‐model Arctic Ocean ``Climate Response Function” (CRF) experiments are analyzed in order to explore the effects of anomalous wind forcing over the Greenland Sea (GS) on poleward ocean heat transport, Atlantic Water (AW) pathways, and the extent of Arctic sea ice. Particular emphasis is placed on the sensitivity of the AW circulation to anomalously strong or weak GS winds in relation to natural variability, the latter manifested as part of the North Atlantic Oscillation (NAO). We find that anomalously strong (weak) GS wind forcing, comparable in strength to a strong positive (negative) NAO index, results in an intensification (weakening) of the poleward AW flow, extending from south of the North Atlantic Subpolar Gyre, through the Nordic Seas, and all... |
| Tipo: Text |
Palavras-chave: Arctic Ocean; Atlantic Water; Sea ice; Wind forcing; Model intercomparison; FAMOS. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00510/62126/66338.pdf |
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| Barton, Benjamin I.; Lique, Camille; Lenn, Yueng‐djern. |
| The Barents Sea is a region of deep water formation where Atlantic Water is converted into cooler, fresher Barents Sea Water. Barents Sea Water properties exhibit variability at seasonal, interannual and decadal timescales. This variability is transferred to Arctic Intermediate Water, which eventually contributes to the deeper branch of the Atlantic Meridional Overturning Circulation. Variations in Barents Sea Water properties are reflected in steric height (contribution of density to sea level variations) that depends on heat and freshwater content, and is a quantity usually derived from in situ observations of water temperature, salinity and pressure that remain sparse during winter in the Barents Sea. This analysis explores the utility of satellite... |
| Tipo: Text |
Palavras-chave: Satellite; Steric height; Freshwater content; Heat content; Arctic Ocean. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00634/74651/74556.pdf |
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| Registros recuperados: 15 | |
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