Blar i Faculty of Mathematics and Natural Sciences på tidsskrift "Biogeosciences"

Viser treff 1-20 av 22

    • Acidification of the Nordic Seas 

      Fransner, Sara Filippa Krusmynta; Fröb, Friederike; Tjiputra, Jerry; Goris, Nadine; Lauvset, Siv Kari; Skjelvan, Ingunn; Jeansson, Emil; Omar, Abdirahman; Chierici, Melissa; Jones, Elizabeth Marie; Fransson, Agneta; Ólafsdóttir, Sólveig R.; Johannessen, Truls; Olsen, Are (Journal article; Peer reviewed, 2022)
      Due to low calcium carbonate saturation states, and winter mixing that brings anthropogenic carbon to the deep ocean, the Nordic Seas and their cold-water corals are vulnerable to ocean acidification. Here, we present a ...

    • Arctic Ocean CO2 uptake: An improved multiyear estimate of the air-sea CO2 flux incorporating chlorophyll a concentrations 

      Yasunaka, Sayaka; Siswanto, Eko; Olsen, Are; Hoppema, Mario; Watanabe, Eiji; Fransson, Agneta Ingrid; Chierici, Melissa; Murata, Akihiko; Lauvset, Siv Kari; Wanninkhof, Rik; Takahashi, Taro; Kosugi, Naohiro; Omar, Abdirahman; van Heuven, Steven; Mathis, Jeremy T. (Peer reviewed; Journal article, 2018-03-22)
      We estimated monthly air–sea CO2 fluxes in the Arctic Ocean and its adjacent seas north of 60∘ N from 1997 to 2014. This was done by mapping partial pressure of CO2 in the surface water (pCO2w) using a self-organizing map ...

    • Compositions of dissolved organic matter in the ice-covered waters above the Aurora hydrothermal vent system, Gakkel Ridge, Arctic Ocean 

      Sert, Muhammed Fatih; Niemann, Helge; Reeves, Eoghan; Granskog, Mats A.; Hand, Kevin P.; Kekäläinen, Timo; Jänis, Janne; Rossel, Pamela; Ferré, Benedicte; Silyakova, Anna; Gründger, Friederike (Journal article; Peer reviewed, 2022)
      Hydrothermal vents modify and displace subsurface dissolved organic matter (DOM) into the ocean. Once in the ocean, this DOM is transported together with elements, particles, dissolved gases and biomass along with the ...

    • Deep-sea sponge grounds as nutrient sinks: Denitrification is common in boreo-Arctic sponges 

      Rooks, Christine; Fang, James Kar-Hei; Mørkved, Pål Tore; Zhao, Rui; Rapp, Hans Tore; Xavier, Joana R; Hoffmann, Friederike (Journal article; Peer reviewed, 2020-03)
      Sponges are commonly known as general nutrient providers for the marine ecosystem, recycling organic matter into various forms of bioavailable nutrients such as ammonium and nitrate. In this study we challenge this view. ...

    • Evaluation of ocean dimethylsulfide concentration and emission in CMIP6 models 

      Bock, Josué; Michou, Martine; Nabat, Pierre; Abe, Manabu; Mulcahy, Jane P.; Oliviè, Dirk Jan Leo; Schwinger, Jörg; Suntharalingam, Parvadha; Tjiputra, Jerry; van Hulten, Marco Marinus Peter; Watanabe, Michio; Yool, Andrew; Séférian, Roland (Journal article; Peer reviewed, 2021)
      Characteristics and trends of surface ocean dimethylsulfide (DMS) concentrations and fluxes into the atmosphere of four Earth system models (ESMs: CNRM-ESM2-1, MIROC-ES2L, NorESM2-LM, and UKESM1-0-LL) are analysed over the ...

    • Experiment design and bacterial abundance control extracellular H2O2 concentrations during four series of mesocosm experiments 

      Hopwood, M. J.; Sanchez, Nicolas; Polyviou, Despo; Leiknes, Øystein; Gallego-Urrea, Julian Alberto; Achterberg, Eric P.; Ardelan, Murat Van; Aristegui, Javier; Bach, Lennart T.; Besiktepe, Sengul; Heriot, Yohann; Kalantzi, Ioanna; Terblylk Kurt, Tuba; Santi, Ioulia; Tsagaraki, Tatiana Margo; Turner, David (Journal article; Peer reviewed, 2020)
      The extracellular concentration of H2O2 in surface aquatic environments is controlled by a balance between photochemical production and the microbial synthesis of catalase and peroxidase enzymes to remove H2O2 from solution. ...

    • Export of calcium carbonate corrosive waters from the East Siberian Sea 

      Anderson, Leif G.; Ek, Jörgen; Ericson, Ylva; Humborg, Christoph; Semiletov, Igor; Sundbom, Magnus; Ulfsbo, Adam (Peer reviewed; Journal article, 2017-04-05)
      The Siberian shelf seas are areas of extensive biogeochemical transformation of organic matter, both of marine and terrestrial origin. This in combination with brine production from sea ice formation results in a cold ...

    • Fe(II) stability in coastal seawater during experiments in Patagonia, Svalbard, and Gran Canaria 

      Hopwood, Mark J.; Santana-González, Carolina; Gallego-Urrea, Julian Alberto; Sanchez, Nicolas; Achterberg, Eric P.; Ardelan, Murat Van; Gledhill, Martha; González-Dávila, Melchor; Hoffmann, Linn; Leiknes, Øystein; Santana-Casiano, Juana Magdalena; Tsagaraki, Tatiana Margo; Turner, David (Journal article; Peer reviewed, 2020-03)
      The speciation of dissolved iron (DFe) in the ocean is widely assumed to consist almost exclusively of Fe(III)-ligand complexes. Yet in most aqueous environments a poorly defined fraction of DFe also exists as Fe(II), the ...

    • First phytoplankton community assessment of the Kong Håkon VII Hav, Southern Ocean, during austral autumn 

      Kauko, Hanna Maria; Assmy, Philipp; Peeken, Ilka; Rózańska-Pluta, Magdalena; Wiktor, Józef M; Bratbak, Gunnar; Singh, Asmita; Ryan-Keogh, Thomas J.; Moreau, Sebastien (Journal article; Peer reviewed, 2022)
      We studied phytoplankton and protozooplankton community composition based on light microscopy, flow cytometry, and photosynthetic pigment data in the Atlantic sector of the Southern Ocean during March 2019 (early austral ...

    • Fluxes of carbon and nutrients to the Iceland Sea surface layer and inferred primary productivity and stoichiometry 

      Jeansson, Emil; Bellerby, Richard; Skjelvan, Ingunn; Frigstad, Helene; Ólafsdóttir, Sólveig R.; Ólafsson, Jón Hjaltalín (Peer reviewed; Journal article, 2015-02-12)
      This study evaluates long-term mean fluxes of carbon and nutrients to the upper 100 m of the Iceland Sea. The study utilises hydro-chemical data from the Iceland Sea time series station (68.00° N, 12.67° W), for the years ...

    • Heterogeneity of impacts of high CO2 on the North Western European shelf 

      Artioli, Yuri; Blackford, Jerry C.; Nondal, Gisle; Bellerby, Richard; Wakelin, Sarah L.; Holt, Jason T.; Butenschön, Momme; Allen, Julian Icarus (Peer reviewed; Journal article, 2014-02-03)
      The increase in atmospheric CO2 is a dual threat to the marine environment: from one side it drives climate change, leading to modifications in water temperature, circulation patterns and stratification intensity; on the ...

    • A model study of the seasonal and long-term North Atlantic surface pCO(2) variability 

      Tjiputra, Jerry; Olsen, Are; Assmann, Karen Margarete; Pfeil, Benjamin; Heinze, Christoph (Peer reviewed; Journal article, 2012-03-05)
      A coupled biogeochemical-physical ocean model is used to study the seasonal and long–term variations of surface pCO2 in the North Atlantic Ocean. The model agrees well with recent underway pCO2 observations from the Surface ...

    • The northern European shelf as an increasing net sink for CO2 

      Becker, Meike; Olsen, Are; Landschützer, Peter; Omar, Abdirahman; Rehder, Gregor; Rödenbeck, Christian; Skjelvan, Ingunn (Journal article; Peer reviewed, 2021)
      We developed a simple method to refine existing open-ocean maps and extend them towards different coastal seas. Using a multi-linear regression we produced monthly maps of surface ocean fCO2 in the northern European coastal ...

    • Ocean acidification in the subpolar North Atlantic: rates and mechanisms controlling pH changes 

      García-Ibáñez, Maribel I.; Zunino, Patricia; Fröb, Friederike; Carracedo, Lidia I.; Ríos, Aida F.; Mercier, Herlé; Olsen, Are; Pérez, Fiz F. (Peer reviewed; Journal article, 2016-06-23)
      Repeated hydrographic sections provide critically needed data on and understanding of changes in basin-wide ocean CO2 chemistry over multi-decadal timescales. Here, high-quality measurements collected at twelve cruises ...

    • On giant shoulders: how a seamount affects the microbialcommunity composition of seawater and sponges 

      Busch, Kathrin; Hanz, Ulrike; Mienis, Furu; Mueller, Benjamin; Franke, Andre; Roberts, Emyr Martyn Tomas; Rapp, Hans Tore; Hentschel, Ute (Journal article; Peer reviewed, 2020)
      Seamounts represent ideal systems to study the influence and interdependency of environmental gradients at a single geographic location. These topographic features represent a prominent habitat for various forms of life, ...

    • Phytoplankton dynamics in contrasting early stage North Atlantic spring blooms: composition, succession, and potential drivers 

      Daniels, Chris; Poulton, Alex J.; Mario, Esposito; Paulsen, Maria Lund; Bellerby, Richard; St. John, Mike; Martin, Adrian P. (Peer reviewed; Journal article, 2015-04-24)
      The spring bloom is a key annual event in the phenology of pelagic ecosystems, making a major contribution to the oceanic biological carbon pump through the production and export of organic carbon. However, there is little ...

    • Projected pH reductions by 2100 might put deep North Atlantic biodiversity at risk 

      Gehlen, Marion; Séférian, Roland; Jones, Daniel O.B.; Roy, Tilla; Roth, Raphael; Barry, James P.; Bopp, Laurent; Doney, Scott C.; Dunne, John P.; Heinze, Christoph; Joos, Fortunat; Orr, James C.; Resplandy, Laure; Segschneider, Joachim; Tjiputra, Jerry (Peer reviewed; Journal article, 2014-12-11)
      This study aims to evaluate the potential for impacts of ocean acidification on North Atlantic deep-sea ecosystems in response to IPCC AR5 Representative Concentration Pathways (RCPs). Deep-sea biota is likely highly ...

    • Quantification of iron-rich volcanogenic dust emissions and deposition over the ocean from Icelandic dust sources 

      Arnalds, Olafur; Ólafsson, Haraldur; Dagsson-Waldhauserova, Pavla (Peer reviewed; Journal article, 2014-12-02)
      Iceland has extremely active dust sources that result in large-scale emissions and deposition on land and at sea. The dust has a volcanogenic origin of basaltic composition with about 10% Fe content. We used two independent ...

    • Riverine impact on future projections of marine primary production and carbon uptake 

      Gao, Shuang; Schwinger, Jörg; Tjiputra, Jerry; Bethke, Ingo; Hartmann, Jens; Mayorga, Emilio; Heinze, Christoph (Journal article; Peer reviewed, 2023)
      Riverine transport of nutrients and carbon from inland waters to the coastal and finally the open ocean alters marine primary production (PP) and carbon (C) uptake regionally and globally. So far, this process has not been ...

    • Southern Ocean controls of the vertical marine δ13C gradient – a modelling study 

      Morée, Anne; Schwinger, Jörg; Heinze, Christoph (Peer reviewed; Journal article, 2018-12-04)
      δ 13 C, the standardised 13C/12C ratio expressed in per mille, is a widely used ocean tracer to study changes in ocean circulation, water mass ventilation, atmospheric pCO2, and the biological carbon pump on timescales ...