• Anthropogenic increase of oceanic pCO2 in the Barents Sea surface water 

      Omar, Abdirahman M.; Johannessen, Truls; Kaltin, Staffan; Olsen, Are (Peer reviewed; Journal article, 2003-12-26)
      We evaluate the change of surface water CO2 partial pressure ( pCO2 sw) in the Barents Sea (BS) between 1967 and 2000–2001. We use temperature (T) data collected during a survey in the BS in 1967 and a relationship between ...
    • Aragonite saturation states and pH in western Norwegian fjords: Seasonal cycles and controlling factors, 2005-2009 

      Omar, Abdirahman; Skjelvan, Ingunn; Erga, Svein Rune; Olsen, Are (Peer reviewed; Journal article, 2016-07-26)
      The uptake of anthropogenic carbon dioxide (CO2) by the ocean leads to a process known as ocean acidification (OA), which lowers the aragonite saturation state (ΩAr) and pH, and this is poorly documented in coastal ...
    • 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 ...
    • Constraining the oceanic uptake and fluxes of greenhouse gases by building an ocean network of certified stations: The ocean component of the Integrated Carbon Observation System, ICOS-Oceans 

      Steinhoff, Tobias; Gkritzalis, Thanos; Lauvset, Siv Kari; Jones, Stephen Daniel; Schuster, Ute; Olsen, Are; Becker, Meike; Bozzano, Roberto; Brunetti, Fabio; Cantoni, Carolina; Cardin, Vanessa; Diverrès, Denis; Fiedler, Björn; Fransson, Agneta; Giani, Michele; Hartman, Sue; Hoppema, Mario; Jeansson, Emil; Johannessen, Truls; Kitidis, Vassilis; Körtzinger, Arne; Landa, Camilla Stegen; Lefèvre, Nathalie; Luchetta, Anna; Naudts, Lieven; Nightingale, Philip D.; Omar, Abdirahman; Pensieri, Sara; Pfeil, Benjamin; Castano Primo, Rocio; Rehder, Gregor; Rutgersson, Anna; Sanders, Richard; Schewe, Ingo; Siena, Giuseppe; Skjelvan, Ingunn; Soltwedel, Thomas; van Heuven, Steven; Watson, Andrew (Peer reviewed; Journal article, 2019)
      The European Research Infrastructure Consortium “Integrated Carbon Observation System” (ICOS) aims at delivering high quality greenhouse gas (GHG) observations and derived data products (e.g., regional GHG-flux maps) for ...
    • Continued warming, salinification and oxygenation of the Greenland Sea gyre 

      Lauvset, Siv Kari; Brakstad, Ailin Dale; Våge, Kjetil; Olsen, Are; Jeansson, Emil; Mork, Kjell Arne (Peer reviewed; Journal article, 2018-06-18)
      The Greenland Sea gyre is one of the few areas where the water column is ventilated through open ocean convection. This process brings both anthropogenic carbon and oxygen from the atmosphere and surface ocean into the ...
    • The effect of wind speed products and wind speed-gas exchange relationships on interannual variability of the air-sea CO2 gas transfer velocity 

      Olsen, Are; Wanninkhof, Rik; Triñanes, Joaquin; Johannessen, Truls (Journal article, 2005)
      The lack of a firm relationship between wind speed (U10) and gas transfer velocity (k) is considered to be one of the factors that hinders accurate quantification of interannual variations of ocean–atmosphere CO2 fluxes. ...
    • Effects of sea-ice and biogeochemical processes and storms on under-ice water fCO2 during the winter-spring transition in the high Arctic Ocean: Implications for sea-air CO2 fluxes 

      Fransson, Agneta Ingrid; Chierici, Melissa; Skjelvan, Ingunn; Olsen, Are; Assmy, Philipp; Peterson, Algot Kristoffer; Spreen, Gunnar; Ward, Brian (Peer reviewed; Journal article, 2017-07)
      We performed measurements of carbon dioxide fugacity (fCO2) in the surface water under Arctic sea ice from January to June 2015 during the Norwegian young sea ICE (N-ICE2015) expedition. Over this period, the ship drifted ...
    • A Framework for the Development, Design and Implementation of a Sustained Arctic Ocean Observing System 

      Lee, Craig M.; Starkweather, Sandy; Eicken, Hajo; Timmermans, Mary-Louise; Wilkinson, Jeremy; Sandven, Stein; Dukhovskoy, Dmitry; Gerland, Sebastian; Grebmeier, Jacqueline; Intrieri, Janet M.; Kang, Sung-Ho; McCammon, Molly; Nguyen, An T.; Polyakov, Igor; Rabe, Benjamin; Sagen, Hanne; Seeyave, Sophie; Volkov, Denis; Beszczynska-Möller, Agnieszka; Chafik, Léon; Dzieciuch, Matthew; Goni, Gustavo; Hamre, Torill; King, Andrew Luke; Olsen, Are; Raj, Roshin Pappukutty; Rossby, Thomas; Skagseth, Øystein; Søiland, Henrik; Sørensen, Kai (Peer reviewed; Journal article, 2019-08-08)
      Rapid Arctic warming drives profound change in the marine environment that have significant socio-economic impacts within the Arctic and beyond, including climate and weather hazards, food security, transportation, ...
    • Global carbon budget 2014 

      Le Quéré, Corinne; Moriarty, Roisin; Andrew, Robbie; Peters, Glen Philip; Ciais, Philippe; Friedlingstein, Pierre; Jones, Samantha D.; Sitch, Stephen; Tans, Pieter; Arneth, Almut; Boden, Thomas A.; Bopp, Laurent; Bozec, Yann; Canadell, Josep G.; Chini, Louise P.; Chevallier, Frédéric; Cosca, Cathrine E.; Harris, Ian C.; Hoppema, Mario; Houghton, Richard A.; House, Joanna I.; Jain, Atul K.; Johannessen, Truls; Kato, Etsushi; Keeling, Ralph F.; Kitidis, Vassilis; Klein Goldewijk, Kees; Koven, Charles D.; Landa, Camilla Stegen; Landschützer, Peter; Lenton, Andrew; Lima, Ivan D.; Marland, Gregg; Mathis, Jeremy T.; Metzl, Nicolas; Nojiri, Yukihiro; Olsen, Are; Ono, Tsuneo; Peng, Shushi; Peters, Wouter; Pfeil, Benjamin; Poulter, Benjamin; Raupach, Michael R.; Regnier, Pierre; Rödenbeck, Christian; Saito, Shu; Salisbury, Joseph E.; Schuster, Ute; Schwinger, Jörg; Séférian, Roland; Segschneider, Joachim; Steinhoff, Tobias; Stocker, Benjamin D.; Sutton, Adrienne J.; Takahashi, Taro; Tilbrook, Bronte; van der Werf, Guido R.; Viovy, Nicolas; Wang, Yingping; Wanninkhof, Rik; Wiltshire, Andrew J.; Zeng, Ning (Peer reviewed; Journal article, 2015-05-08)
      Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the ...
    • Global Carbon Budget 2015 

      Le Quéré, Corinne; Moriarty, Roisin; Andrew, Robbie; Canadell, Josep G.; Sitch, Stephen; Korsbakken, Jan Ivar; Friedlingstein, Pierre; Peters, Glen Philip; Andres, Robert J.; Boden, Thomas A.; Houghton, Richard A.; House, Joanna I.; Keeling, Ralph F.; Tans, Pieter; Arneth, Almut; Bakker, Dorothée C.E.; Barbero, Leticia; Bopp, Laurent; Chang, Joseph; Chevallier, Frédéric; Chini, Louise P.; Ciais, Philippe; Fader, Marianela; Feely, Richard A.; Gkritzalis, Thanos; Harris, Ian; Hauck, Judith; Ilyina, Tatiana; Jain, Atul K.; Kato, Etsushi; Kitidis, Vassilis; Goldewijk, K. Klein; Koven, Charles Dunbar; Landschützer, Peter; Lauvset, Siv Kari; Lefévre, Nathalie; Lenton, Andrew; Lima, Ivan D.; Metzl, Nicolas; Millero, Frank; Munro, David R.; Murata, Aki; Nabel, Julia E.M.S.; Nakaoka, Shinichirou; Nojiri, Yukihiro; O'Brien, Kevin; Olsen, Are; Ono, Tsuneo; Pérez, Fiz Fernández; Pfeil, Benjamin; Pierrot, Denis; Poulter, Benjamin; Rehder, Gregor; Rödenbeck, Christian; Saito, Shu; Schuster, Ute; Schwinger, Jörg; Séférian, Roland; Steinhoff, Tobias; Stocker, Benjamin D.; Sutton, Adrienne J.; Takahashi, Taro; Tilbrook, Bronte; van der Laan-Luijkx, Ingrid Theodora; van der Werf, Guido R.; van Heuven, Steven; Vandemark, Douglas; Viovy, Nicolas; Wiltshire, Andy; Zaehle, Sönke; Zeng, Ning (Peer reviewed; Journal article, 2015-12-07)
      Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the ...
    • Global Carbon Budget 2016 

      Le Quéré, Corinne; Andrew, Robbie; Canadell, Josep G.; Sitch, Stephen; Korsbakken, Jan Ivar; Peters, Glen Philip; Manning, Andrew C; Boden, Thomas A; Tans, Pieter P; Houghton, Richard A; Keeling, Ralph F; Alin, Simone; Andrews, Oliver D; Anthoni, Peter; Barbero, Leticia; Bopp, Laurent; Chevallier, Frederic; Chini, Louise P; Ciais, Philippe; Currie, Kim; Delire, Christine; Doney, Scott C; Friedlingstein, Pierre; Gkritzalis, Thanos; Harris, Ian; Hauck, Judith; Haverd, Vanessa; Hoppema, Mario; Klein Goldewijk, Kees; Jain, Atul K; Kato, Etsushi; Körtzinger, Arne; Landschutzer, Peter; Lefevre, Nathalie; Lenton, Andrew; Lienert, Sebastian; Lombardozzi, Danica; Melton, Joe R; Metzl, Nicolas; Millero, Frank; Monteiro, Pedro M S; Munro, David R; Nabel, Julia E M S; Nakaoka, Shin-Ichiro; O'Brien, Kevin; Olsen, Are; Omar, Abdirahman; Pierrot, Denis; Ono, Tsuneo; Poulter, Benjamin; Rödenbeck, Christian; Salisbury, Joe; Schuster, Ute; Schwinger, Jörg; Seferian, Roland; Skjelvan, Ingunn; Stocker, Benjamin D; Sutton, Adrienne J; Takahashi, Taro; Tian, Hanqin; Tilbrook, Bronte; Van Der Laan-Luijkx, Ingrid T; Van Der Werf, Guido R; Viovy, Nicolas; Walker, Anthony P; Wiltshire, Andrew J; Zaehle, Sönke (Peer reviewed; Journal article, 2016-11-14)
      Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere – the “global carbon budget” – is important to better understand the global ...
    • Global Carbon Budget 2020 

      Friedlingstein, Pierre; O'Sullivan, Michael; Jones, Matthew W.; Andrew, Robbie; Hauck, Judith; Olsen, Are; Peters, Glen Philip; Peters, Wouter; Pongratz, Julia; Sitch, Stephen; Le Quéré, Corinne; Canadell, Josep G.; Ciais, Philippe; Jackson, Robert B.; Alin, Simone; Aragão, Luiz E.O.C.; Arneth, Almut; Arora, Vivek K.; Bates, Nicholas R.; Becker, Meike; Benoit-Cattin, Alice; Bittig, Henry C.; Bopp, Laurent; Bultan, Selma; Chandra, Naveen; Chevallier, Frédéric; Chini, Louise P.; Evans, Wiley; Florentie, Liesbeth; Forster, Piers M.; Gasser, Thomas; Gehlen, Marion; Gilfillan, Dennis; Gkritzalis, Thanos; Gregor, Luke; Gruber, Nicolas; Harris, Ian; Hartung, Kerstin; Haverd, Vanessa; Houghton, Richard A.; Ilyina, Tatiana; Jain, Atul K.; Joetzjer, Emilie; Kadono, Koji; Kato, Etsushi; Kitidis, Vassilis; Korsbakken, Jan Ivar; Landschützer, Peter; Lefevre, Nathalie; Lenton, Andrew; Lienert, Sebastian; Liu, Zhu; Lombardozzi, Danica; Marland, Gregg; Metzl, Nicolas; Munro, David; Nabel, Julia E.M.S.; Nakaoka, Shin-Ichiro; Niwa, Yosuke; O'Brien, Kevin M.; Ono, Tsuneo; Palmer, Paul I.; Pierrot, Denis; Poulter, Ben; Resplandy, Laure; Robertson, Eddy; Rödenbeck, Christian; Schwinger, Jörg; Séférian, Roland; Skjelvan, Ingunn; Smith, Adam J.P.; Sutton, Adrienne; Tanhua, Toste; Tans, Pieter P.; Tian, Hanqin; Tilbrook, Bronte; Van Der Werf, Guido; Vuichard, Nicolas; Walker, Anthony P.; Wanninkhof, Rik; Watson, Andrew; Willis, David; Wiltshire, Andy; Yuan, Wenping; Yue, Xu; Zaehle, Sönke (Journal article; Peer reviewed, 2020)
      Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate – the “global carbon budget” – is important to better ...
    • A global monthly climatology of oceanic total dissolved inorganic carbon: a neural network approach 

      Broullón, Daniel; Velo, Antón; Hoppema, Mario; Olsen, Are; Takahashi, Taro; Key, Robert M.; Tanhua, Toste; Santana-Casiano, J. Magdalena; Kozyr, Alex; Perez, Fiz F. (Journal article; Peer reviewed, 2020)
      Anthropogenic emissions of CO2 to the atmosphere have modified the carbon cycle for more than 2 centuries. As the ocean stores most of the carbon on our planet, there is an important task in unraveling the natural and ...
    • Inorganic Carbon and Water Masses in the Irminger Sea since 1991 

      Fröb, Friederike; Olsen, Are; Pérez, Fiz F.; García-Ibáñez, Maribel I.; Jeansson, Emil; Omar, Abdirahman; Lauvset, Siv K. (Peer reviewed; Journal article, 2017-02-17)
      The subpolar gyre region in the North Atlantic is a major sink for anthropogenic carbon. While the storage rates show large interannual variability related to atmospheric forcing, less is known about variability in the ...
    • Interannual sea-air CO2 flux variability from an observation-driven ocean mixed-layer scheme 

      Rödenbeck, Christian; Bakker, Dorothée C.E.; Metzl, Nicolas; Olsen, Are; Sabine, Christopher; Cassar, Nicolas; Reum, Friedemann; Keeling, Ralph F.; Heimann, Martin (Peer reviewed; Journal article, 2014-09-01)
      Interannual anomalies in the sea–air carbon dioxide (CO2) exchange have been estimated from surface-ocean CO2 partial pressure measurements. Available data are sufficient to constrain these anomalies in large parts of the ...
    • Interannual variability in the wintertime air–sea flux of carbon dioxide in the northern North Atlantic, 1981–2001 

      Olsen, Are; Bellerby, Richard G. J.; Johannessen, Truls; Omar, Abdirahman M.; Skjelvan, Ingunn (Peer reviewed; Journal article, 2003)
      Gridded fields of sea surface temperature (SST), sea level pressure (SLP), and wind speed were used in combination with data for the atmospheric mole fraction of CO2 and an empirical relationship between measured values ...
    • Long-term surface pCO2 trends from observations and models 

      Tjiputra, Jerry; Olsen, Are; Bopp, Laurent; Lenton, Andrew; Pfeil, Benjamin; Roy, Tilla; Segschneider, Joachim; Totterdell, Ian; Heinze, Christoph (Peer reviewed; Journal article, 2014-05-19)
      We estimate regional long-term surface ocean pCO2 growth rates using all available underway and bottled biogeochemistry data collected over the past four decades. These observed regional trends are compared with those ...
    • Magnitude and Origin of the Anthropogenic CO2 Increase and the 13C Suess Effect in the Nordic Seas since 1981 

      Olsen, Are; Abdirahman, Omar M.; Bellerby, Richard G. J.; Johannessen, Truls; Ninnemann, Ulysses Silas; Brown, Kelly R.; Olsson, K. Anders; Olafsson, Jon; Nondal, Gisle; Kivimäe, Caroline; Kringstad, Solveig; Neill, Craig; Olafsdottir, Solveig (Peer reviewed; Journal article, 2006-09-29)
      This study evaluates the anthropogenic changes of CO2 (∆Cant) and δ13C (∆δ13Cant) in the Nordic seas, the northern limb of the Atlantic Meridional Overturning Circulation, that took place between 1981 and 2002/03. The ...
    • Mg/Ca ratios in the planktonic foraminifer Neogloboquadrina pachyderma (sinistral) in the northern North Atlantic/Nordic Seas 

      Meland, Marius Yddal; Jansen, Eystein; Elderfield, Henry; Dokken, Trond Martin; Olsen, Are; Bellerby, Richard G. J. (Peer reviewed; Journal article, 2006-06-15)
      In core top samples in the Nordic Seas, Mg/Ca ratios of N. pachyderma (sin.) are generally consistent with previous high-latitude calibration data but do not reflect the modern calcification temperature gradient from 2ºC ...
    • 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 ...