Articles | Volume 16, issue 2
https://doi.org/10.5194/os-16-483-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-16-483-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Apr 2020
Research article |
| 24 Apr 2020
| 24 Apr 2020
Mass, nutrients and dissolved organic carbon (DOC) lateral transports off northwest Africa during fall 2002 and spring 2003
Departamento de Física, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Francisco Machín
Departamento de Física, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Ángeles Marrero-Díaz
Departamento de Física, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Ángel Rodríguez-Santana
Departamento de Física, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Antonio Martínez-Marrero
Instituto de Oceanografía y Cambio Global, Universidad de Las Palmas de Gran Canaria, Telde, Spain
Javier Arístegui
Instituto de Oceanografía y Cambio Global, Universidad de Las Palmas de Gran Canaria, Telde, Spain
Carlos Manuel Duarte
Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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Marta Veny, Borja Aguiar-González, Ángeles Marrero-Díaz, Tania Pereira-Vázquez, and Ángel Rodríguez-Santana
Ocean Sci., 20, 389–415, https://doi.org/10.5194/os-20-389-2024, https://doi.org/10.5194/os-20-389-2024, 2024
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This study examines the seasonal patterns of chlorophyll-a (chl-a) blooms in the Bransfield Strait using remote sensing data supported by novel and historical in situ observations. Through satellite data we show that we can identify two distinct phytoplankton niches along a thermal front known as the Peninsula Front: the Transitional Bellingshausen Water and Transitional Weddell Water pools. These findings enable the first climatological description of the chl-a blooms in the Bransfield Strait.
Christian Lønborg, Cátia Carreira, Gwenaël Abril, Susana Agustí, Valentina Amaral, Agneta Andersson, Javier Arístegui, Punyasloke Bhadury, Mariana B. Bif, Alberto V. Borges, Steven Bouillon, Maria Ll. Calleja, Luiz C. Cotovicz Jr., Stefano Cozzi, Maryló Doval, Carlos M. Duarte, Bradley Eyre, Cédric G. Fichot, E. Elena García-Martín, Alexandra Garzon-Garcia, Michele Giani, Rafael Gonçalves-Araujo, Renee Gruber, Dennis A. Hansell, Fuminori Hashihama, Ding He, Johnna M. Holding, William R. Hunter, J. Severino P. Ibánhez, Valeria Ibello, Shan Jiang, Guebuem Kim, Katja Klun, Piotr Kowalczuk, Atsushi Kubo, Choon-Weng Lee, Cláudia B. Lopes, Federica Maggioni, Paolo Magni, Celia Marrase, Patrick Martin, S. Leigh McCallister, Roisin McCallum, Patricia M. Medeiros, Xosé Anxelu G. Morán, Frank E. Muller-Karger, Allison Myers-Pigg, Marit Norli, Joanne M. Oakes, Helena Osterholz, Hyekyung Park, Maria Lund Paulsen, Judith A. Rosentreter, Jeff D. Ross, Digna Rueda-Roa, Chiara Santinelli, Yuan Shen, Eva Teira, Tinkara Tinta, Guenther Uher, Masahide Wakita, Nicholas Ward, Kenta Watanabe, Yu Xin, Youhei Yamashita, Liyang Yang, Jacob Yeo, Huamao Yuan, Qiang Zheng, and Xosé Antón Álvarez-Salgado
Earth Syst. Sci. Data, 16, 1107–1119, https://doi.org/10.5194/essd-16-1107-2024, https://doi.org/10.5194/essd-16-1107-2024, 2024
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In this paper, we present the first edition of a global database compiling previously published and unpublished measurements of dissolved organic matter (DOM) collected in coastal waters (CoastDOM v1). Overall, the CoastDOM v1 dataset will be useful to identify global spatial and temporal patterns and to facilitate reuse in studies aimed at better characterizing local biogeochemical processes and identifying a baseline for modelling future changes in coastal waters.
Afrah Alothman, Daffne López-Sandoval, Carlos M. Duarte, and Susana Agustí
Biogeosciences, 20, 3613–3624, https://doi.org/10.5194/bg-20-3613-2023, https://doi.org/10.5194/bg-20-3613-2023, 2023
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Biogeosciences, 20, 1605–1619, https://doi.org/10.5194/bg-20-1605-2023, https://doi.org/10.5194/bg-20-1605-2023, 2023
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Allanah Joy Paul, Lennart Thomas Bach, Javier Arístegui, Elisabeth von der Esch, Nauzet Hernández-Hernández, Jonna Piiparinen, Laura Ramajo, Kristian Spilling, and Ulf Riebesell
Biogeosciences, 19, 5911–5926, https://doi.org/10.5194/bg-19-5911-2022, https://doi.org/10.5194/bg-19-5911-2022, 2022
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We investigated how different deep water chemistry and biology modulate the response of surface phytoplankton communities to upwelling in the Peruvian coastal zone. Our results show that the most influential drivers were the ratio of inorganic nutrients (N : P) and the microbial community present in upwelling source water. These led to unexpected and variable development in the phytoplankton assemblage that could not be predicted by the amount of inorganic nutrients alone.
Kai G. Schulz, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Isabel Baños, Tim Boxhammer, Dirk Erler, Maricarmen Igarza, Verena Kalter, Andrea Ludwig, Carolin Löscher, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Elisabeth von der Esch, Bess B. Ward, and Ulf Riebesell
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Upwelling of nutrient-rich deep waters to the surface make eastern boundary upwelling systems hot spots of marine productivity. This leads to subsurface oxygen depletion and the transformation of bioavailable nitrogen into inert N2. Here we quantify nitrogen loss processes following a simulated deep water upwelling. Denitrification was the dominant process, and budget calculations suggest that a significant portion of nitrogen that could be exported to depth is already lost in the surface ocean.
Nadia Burgoa, Francisco Machín, Ángel Rodríguez-Santana, Ángeles Marrero-Díaz, Xosé Antón Álvarez-Salgado, Bieito Fernández-Castro, María Dolores Gelado-Caballero, and Javier Arístegui
Ocean Sci., 17, 769–788, https://doi.org/10.5194/os-17-769-2021, https://doi.org/10.5194/os-17-769-2021, 2021
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The circulation patterns in the confluence of the North Atlantic subtropical and tropical gyres delimited by the Cape Verde Front were examined during a field cruise in summer 2017. The collected hydrographic data, O2 and inorganic nutrients along the perimeter of a closed box embracing the Cape Verde Frontal Zone allowed for the independent estimation of the transport of these properties.
Lennart Thomas Bach, Allanah Joy Paul, Tim Boxhammer, Elisabeth von der Esch, Michelle Graco, Kai Georg Schulz, Eric Achterberg, Paulina Aguayo, Javier Arístegui, Patrizia Ayón, Isabel Baños, Avy Bernales, Anne Sophie Boegeholz, Francisco Chavez, Gabriela Chavez, Shao-Min Chen, Kristin Doering, Alba Filella, Martin Fischer, Patricia Grasse, Mathias Haunost, Jan Hennke, Nauzet Hernández-Hernández, Mark Hopwood, Maricarmen Igarza, Verena Kalter, Leila Kittu, Peter Kohnert, Jesus Ledesma, Christian Lieberum, Silke Lischka, Carolin Löscher, Andrea Ludwig, Ursula Mendoza, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Joaquin Ortiz Cortes, Jonna Piiparinen, Claudia Sforna, Kristian Spilling, Sonia Sanchez, Carsten Spisla, Michael Sswat, Mabel Zavala Moreira, and Ulf Riebesell
Biogeosciences, 17, 4831–4852, https://doi.org/10.5194/bg-17-4831-2020, https://doi.org/10.5194/bg-17-4831-2020, 2020
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The eastern boundary upwelling system off Peru is among Earth's most productive ocean ecosystems, but the factors that control its functioning are poorly constrained. Here we used mesocosms, moored ~ 6 km offshore Peru, to investigate how processes in plankton communities drive key biogeochemical processes. We show that nutrient and light co-limitation keep productivity and export at a remarkably constant level while stoichiometry changes strongly with shifts in plankton community structure.
Celina Burkholz, Neus Garcias-Bonet, and Carlos M. Duarte
Biogeosciences, 17, 1717–1730, https://doi.org/10.5194/bg-17-1717-2020, https://doi.org/10.5194/bg-17-1717-2020, 2020
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Seagrass meadows store carbon in their biomass and sediments, but they have also been shown to be sources of carbon dioxide (CO2) and methane (CH4). We experimentally investigated the effect of warming and prolonged darkness on CO2 and CH4 fluxes in Red Sea seagrass (Halophila stipulacea) communities. Our results indicated that sublethal warming may lead to increased emissions of greenhouse gases from seagrass meadows which may contribute to further enhance global warming.
Mark J. Hopwood, Nicolas Sanchez, Despo Polyviou, Øystein Leiknes, Julián Alberto Gallego-Urrea, Eric P. Achterberg, Murat V. Ardelan, Javier Aristegui, Lennart Bach, Sengul Besiktepe, Yohann Heriot, Ioanna Kalantzi, Tuba Terbıyık Kurt, Ioulia Santi, Tatiana M. Tsagaraki, and David Turner
Biogeosciences, 17, 1309–1326, https://doi.org/10.5194/bg-17-1309-2020, https://doi.org/10.5194/bg-17-1309-2020, 2020
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Hydrogen peroxide, H2O2, is formed naturally in sunlight-exposed water by photochemistry. At high concentrations it is undesirable to biological cells because it is a stressor. Here, across a range of incubation experiments in diverse marine environments (Gran Canaria, the Mediterranean, Patagonia and Svalbard), we determine that two factors consistently affect the H2O2 concentrations irrespective of geographical location: bacteria abundance and experiment design.
Kimberlee Baldry, Vincent Saderne, Daniel C. McCorkle, James H. Churchill, Susana Agusti, and Carlos M. Duarte
Biogeosciences, 17, 423–439, https://doi.org/10.5194/bg-17-423-2020, https://doi.org/10.5194/bg-17-423-2020, 2020
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The carbon cycling of coastal ecosystems over large spatial scales is not well measured relative to the open ocean. In this study we measure the carbonate system in the three habitats, to measure ecosystem-driven changes compared to offshore waters. We find (1) 70 % of seagrass meadows and mangrove forests show large ecosystem-driven changes, and (2) mangrove forests show strong and consistent trends over large scales, while seagrass meadows display more variability.
Miguel Agulles, Gabriel Jordà, Burt Jones, Susana Agustí, and Carlos M. Duarte
Ocean Sci., 16, 149–166, https://doi.org/10.5194/os-16-149-2020, https://doi.org/10.5194/os-16-149-2020, 2020
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The Red Sea holds one of the most diverse marine ecosystems in the world, although fragile and vulnerable to ocean warming. To better understand the long-term variability and trends of temperature in the whole water column, we produce a 3-D gridded temperature product (TEMPERSEA) for the period 1958–2017, based on a large number of in situ observations, covering the Red Sea and the Gulf of Aden.
Susana Agustí, Jeffrey W. Krause, Israel A. Marquez, Paul Wassmann, Svein Kristiansen, and Carlos M. Duarte
Biogeosciences, 17, 35–45, https://doi.org/10.5194/bg-17-35-2020, https://doi.org/10.5194/bg-17-35-2020, 2020
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We found that 24 % of the total diatoms community in the Arctic water column (450 m depth) was located below the photic layer. Healthy diatom communities in active spring–bloom stages remained in the photic layer. Dying diatom communities exported a large fraction of the biomass to the aphotic zone, fuelling carbon sequestration and benthic ecosystems in the Arctic. The results of the study conform to a conceptual model where diatoms grow during the bloom until silicic acid stocks are depleted.
Daffne C. López-Sandoval, Katherine Rowe, Paloma Carillo-de-Albonoz, Carlos M. Duarte, and Susana Agustí
Biogeosciences, 16, 2983–2995, https://doi.org/10.5194/bg-16-2983-2019, https://doi.org/10.5194/bg-16-2983-2019, 2019
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We addressed how the intertwined effect of temperature and nutrients modulates the metabolic response of planktonic communities in the Red Sea, one of the warmest seas on earth. Our study unveiled that photosynthesis increases at a faster pace than respiration rates for this group of organisms formed by microalgae, bacteria, and drifting animals. This anomaly is likely due to the nature of the basin where the warmest waters are frequently enriched with nutrients, which favours microalgae growth.
Susann Rossbach, Vincent Saderne, Andrea Anton, and Carlos M. Duarte
Biogeosciences, 16, 2635–2650, https://doi.org/10.5194/bg-16-2635-2019, https://doi.org/10.5194/bg-16-2635-2019, 2019
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Giant clams including the species Tridacna maxima are unique among bivalves as they live in symbiosis with unicellular algae and generally function as net photoautotrophs. Light is therefore crucial for these species to thrive. We show that net calcification and photosynthetic rates of T. maxima are light dependent, with maximum rates at conditions comparable to 4 m water depth, reflected also in the depth-related distribution in the Red Sea with maximum abundances in shallow sunlit coral reefs.
Neus Garcias-Bonet, Raquel Vaquer-Sunyer, Carlos M. Duarte, and Núria Marbà
Biogeosciences, 16, 167–175, https://doi.org/10.5194/bg-16-167-2019, https://doi.org/10.5194/bg-16-167-2019, 2019
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We assess the impact of warming on nitrogen fixation in three key Mediterranean macrophytes by experimentally measuring sediment nitrogen fixation rates at current and projected seawater temperature by 2100 under a scenario of moderate greenhouse gas emissions. The temperature dependence of nitrogen fixation could potentially increase rates by 37 % by the end of the century, with important consequences for primary production in coastal ecosystems.
Neus Garcias-Bonet, Marco Fusi, Muhammad Ali, Dario R. Shaw, Pascal E. Saikaly, Daniele Daffonchio, and Carlos M. Duarte
Biogeosciences, 15, 7333–7346, https://doi.org/10.5194/bg-15-7333-2018, https://doi.org/10.5194/bg-15-7333-2018, 2018
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Nitrogen (N) loads are detrimental for coastal ecosystems. We measured the balance between N losses and gains in a Red Sea seagrass. The N loss was higher than N2 fixed, pointing out the importance of seagrasses in removing N from the system. N2 losses increased with temperature. Therefore, the forecasted warming could increase the N2 flux to the atmosphere, potentially impacting seagrass productivity and their capacity to mitigate climate change but also enhancing their potential N removal.
Ariane Arias-Ortiz, Pere Masqué, Jordi Garcia-Orellana, Oscar Serrano, Inés Mazarrasa, Núria Marbà, Catherine E. Lovelock, Paul S. Lavery, and Carlos M. Duarte
Biogeosciences, 15, 6791–6818, https://doi.org/10.5194/bg-15-6791-2018, https://doi.org/10.5194/bg-15-6791-2018, 2018
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Efforts to include tidal marsh, mangrove and seagrass ecosystems in existing carbon mitigation strategies are limited by a lack of estimates of carbon accumulation rates (CARs). We discuss the use of 210Pb dating to determine CARs in these habitats, which are often composed of heterogeneous sediments and affected by sedimentary processes. Results show that obtaining reliable geochronologies in these systems is ambitious, but estimates of mean 100-year CARs are mostly secure within 20 % error.
Jeffrey W. Krause, Carlos M. Duarte, Israel A. Marquez, Philipp Assmy, Mar Fernández-Méndez, Ingrid Wiedmann, Paul Wassmann, Svein Kristiansen, and Susana Agustí
Biogeosciences, 15, 6503–6517, https://doi.org/10.5194/bg-15-6503-2018, https://doi.org/10.5194/bg-15-6503-2018, 2018
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Diatoms can dominate the Arctic Ocean spring bloom, the key annual event for regional food webs. Diatom growth requires silicon and this nutrient has been declining in the European Arctic. This study communicates an unprecedented combination of silicon-cycling measurements around Svalbard during the spring and shows that dissolved silicon can limit diatom production. These results suggest an important coupling of silicon and carbon cycling during the spring bloom in the European Arctic.
Mallory A. Sea, Neus Garcias-Bonet, Vincent Saderne, and Carlos M. Duarte
Biogeosciences, 15, 5365–5375, https://doi.org/10.5194/bg-15-5365-2018, https://doi.org/10.5194/bg-15-5365-2018, 2018
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Mangroves are capable of storing carbon in their roots, leaves, and in the sediment; however they can also emit carbon as greenhouse gases (GHG) to the atmosphere. In this study, we collected sediment cores and calculated GHG flux rates from mangrove forests along the Red Sea coastline. Using flux rates reported in this study, we determined that Red Sea mangroves are net carbon sinks, storing more carbon than they emit. This study provides rationale to conserve and expand Red Sea mangroves.
Aisling Fontanini, Alexandra Steckbauer, Sam Dupont, and Carlos M. Duarte
Biogeosciences, 15, 3717–3729, https://doi.org/10.5194/bg-15-3717-2018, https://doi.org/10.5194/bg-15-3717-2018, 2018
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Invertebrate species of the Gullmar Fjord (Sweden) were exposed to four different treatments (high/low oxygen and low/high CO2) and respiration measured. Respiration responses of species of contrasting habitats and life-history strategies to single and multiple stressors was evaluated. Results show that the responses of the respiration were highly species specific as we observed both synergetic as well as antagonistic responses, and neither phylum nor habitat explained trends in respiration.
Francesca Iuculano, Carlos Maria Duarte, Núria Marbà, and Susana Agustí
Biogeosciences, 14, 5069–5075, https://doi.org/10.5194/bg-14-5069-2017, https://doi.org/10.5194/bg-14-5069-2017, 2017
Melchor González-Dávila, J. Magdalena Santana Casiano, and Francisco Machín
Biogeosciences, 14, 3859–3871, https://doi.org/10.5194/bg-14-3859-2017, https://doi.org/10.5194/bg-14-3859-2017, 2017
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The Mauritanian–Cap Vert upwelling is shown to be sensitive to climate change forcing on upwelling processes, which strongly affects the CO2 surface distribution, ocean acidification rates, and air–sea CO2 exchange. We confirmed an upwelling intensification, an increase in the CO2 outgassing, and an important decrease in the pH of the surface waters. Upwelling areas are poorly studied and VOS lines are shown as one of the most significant contributors to our knowledge of the ocean's response.
Carlos M. Duarte
Biogeosciences, 14, 301–310, https://doi.org/10.5194/bg-14-301-2017, https://doi.org/10.5194/bg-14-301-2017, 2017
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Vegetated coastal habitats (mangroves, seagrass meadows, salt marshes and macroalgal beds) are key contributors to the marine carbon budget, but remain hidden in the representation of the coastal carbon budget. While they have been acknowledged to play an important role in carbon burial, this is small compared to the export flow, which may lead to carbon sequestration beyond these habitats. The carbon fluxes supported by vegetated coastal habitats are globally relevant.
Oscar Serrano, Paul S. Lavery, Carlos M. Duarte, Gary A. Kendrick, Antoni Calafat, Paul H. York, Andy Steven, and Peter I. Macreadie
Biogeosciences, 13, 4915–4926, https://doi.org/10.5194/bg-13-4915-2016, https://doi.org/10.5194/bg-13-4915-2016, 2016
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We explored the relationship between organic carbon and mud (i.e. silt and clay) contents in seagrass ecosystems to address whether mud can be used to predict soil C content, thereby enabling robust scaling up exercises at a low cost as part of blue carbon stock assessments. We show that mud is not a universal proxy for blue carbon content in seagrass ecosystems, but it can be used to estimate soil Corg content when low biomass seagrass species (i.e. Zostera, Halodule and Halophila) are present.
Oscar Serrano, Aurora M. Ricart, Paul S. Lavery, Miguel Angel Mateo, Ariane Arias-Ortiz, Pere Masque, Mohammad Rozaimi, Andy Steven, and Carlos M. Duarte
Biogeosciences, 13, 4581–4594, https://doi.org/10.5194/bg-13-4581-2016, https://doi.org/10.5194/bg-13-4581-2016, 2016
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The recent focus on carbon (C) trading has intensified interest in "Blue Carbon" – C sequestered by coastal vegetation. However, the factors influencing C storage are poorly understood. The patterns found in this study support that C storage in Posidonia seagrass soils is influenced by interactions of biological, chemical and physical factors within the meadow. We conclude that there is a need to improve global estimates accounting for biogeochemical factors driving variability within habitats.
D. Krause-Jensen, C. M. Duarte, I. E. Hendriks, L. Meire, M. E. Blicher, N. Marbà, and M. K. Sejr
Biogeosciences, 12, 4895–4911, https://doi.org/10.5194/bg-12-4895-2015, https://doi.org/10.5194/bg-12-4895-2015, 2015
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The Arctic Ocean is considered the most vulnerable ecosystem to ocean acidification (OA), but very little information is available on natural variability of pH in the Arctic coastal zone. We report pH variability at various scales in a Greenland fjord. Variability ranged up to 0.2-0.3 pH units horizontally and vertically in the fjord, between seasons and on diel basis in kelp forests and was extreme in tidal pools. Overall, primary producers played a fundamental role in producing mosaics of pH.
L. S. García-Corral, E. Barber, A. Regaudie-de-Gioux, S. Sal, J. M. Holding, S. Agustí, N. Navarro, P. Serret, P. Mozetič, and C. M. Duarte
Biogeosciences, 11, 4529–4540, https://doi.org/10.5194/bg-11-4529-2014, https://doi.org/10.5194/bg-11-4529-2014, 2014
I. E. Hendriks, Y. S. Olsen, L. Ramajo, L. Basso, A. Steckbauer, T. S. Moore, J. Howard, and C. M. Duarte
Biogeosciences, 11, 333–346, https://doi.org/10.5194/bg-11-333-2014, https://doi.org/10.5194/bg-11-333-2014, 2014
S. Lasternas, M. Piedeleu, P. Sangrà, C. M. Duarte, and S. Agustí
Biogeosciences, 10, 2129–2143, https://doi.org/10.5194/bg-10-2129-2013, https://doi.org/10.5194/bg-10-2129-2013, 2013
R. Vaquer-Sunyer, C. M. Duarte, J. Holding, A. Regaudie-de-Gioux, L. S. García-Corral, M. Reigstad, and P. Wassmann
Biogeosciences, 10, 1451–1469, https://doi.org/10.5194/bg-10-1451-2013, https://doi.org/10.5194/bg-10-1451-2013, 2013
M. Alcaraz, R. Almeda, E. Saiz, A. Calbet, C. M. Duarte, S. Agustí, R. Santiago, and A. Alonso
Biogeosciences, 10, 689–697, https://doi.org/10.5194/bg-10-689-2013, https://doi.org/10.5194/bg-10-689-2013, 2013
Related subject area
Approach: In situ Observations | Depth range: All Depths | Geographical range: Deep Seas: North Atlantic | Phenomena: Current Field
3D reconstruction of ocean velocity from high-frequency radar and acoustic Doppler current profiler: a model-based assessment study
Surface predictor of overturning circulation and heat content change in the subpolar North Atlantic
Arctic Mediterranean exchanges: a consistent volume budget and trends in transports from two decades of observations
Atlantic Meridional Overturning Circulation at 14.5° N in 1989 and 2013 and 24.5° N in 1992 and 2015: volume, heat, and freshwater transports
Atlantic water flow through the Faroese Channels
A stable Faroe Bank Channel overflow 1995–2015
Compensation between meridional flow components of the Atlantic MOC at 26° N
Deep drivers of mesoscale circulation in the central Rockall Trough
Impact of a 30% reduction in Atlantic meridional overturning during 2009–2010
Atlantic transport variability at 25° N in six hydrographic sections
On the seasonal cycles and variability of Florida Straits, Ekman and Sverdrup transports at 26° N in the Atlantic Ocean
The contribution of eastern-boundary density variations to the Atlantic meridional overturning circulation at 26.5° N
Ivan Manso-Narvarte, Erick Fredj, Gabriel Jordà, Maristella Berta, Annalisa Griffa, Ainhoa Caballero, and Anna Rubio
Ocean Sci., 16, 575–591, https://doi.org/10.5194/os-16-575-2020, https://doi.org/10.5194/os-16-575-2020, 2020
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Our main aim is to study the feasibility of reconstructing oceanic currents by extending the data obtained from coastal multiplatform observatories to nearby areas in 3D in the SE Bay of Biscay. To that end, two different data-reconstruction methods with different approaches were tested, providing satisfactory results. This work is a first step towards the real applicability of these methods in this study area, and it shows the capabilities of the methods for a wide range of applications.
Damien G. Desbruyères, Herlé Mercier, Guillaume Maze, and Nathalie Daniault
Ocean Sci., 15, 809–817, https://doi.org/10.5194/os-15-809-2019, https://doi.org/10.5194/os-15-809-2019, 2019
Short summary
Short summary
In the North Atlantic, ocean currents transport warm waters northward in the upper water column, and cold waters southwards at depth. This circulation is here reconstructed from surface data and thermodynamics theory. Its driving role in recent temperature changes (1993–2017) in the North Atlantic is evidenced, and predictions of near-future variability (5 years) are provided and discussed.
Svein Østerhus, Rebecca Woodgate, Héðinn Valdimarsson, Bill Turrell, Laura de Steur, Detlef Quadfasel, Steffen M. Olsen, Martin Moritz, Craig M. Lee, Karin Margretha H. Larsen, Steingrímur Jónsson, Clare Johnson, Kerstin Jochumsen, Bogi Hansen, Beth Curry, Stuart Cunningham, and Barbara Berx
Ocean Sci., 15, 379–399, https://doi.org/10.5194/os-15-379-2019, https://doi.org/10.5194/os-15-379-2019, 2019
Short summary
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Two decades of observations of the Arctic Mediterranean (AM) exchanges show that the exchanges have been stable in terms of volume transport during a period when many other components of the global climate system have changed. The total AM import is found to be 9.1 Sv and has a seasonal variation in amplitude close to 1 Sv, and maximum import in October. Roughly one-third of the imported water leaves the AM as surface outflow.
Yao Fu, Johannes Karstensen, and Peter Brandt
Ocean Sci., 14, 589–616, https://doi.org/10.5194/os-14-589-2018, https://doi.org/10.5194/os-14-589-2018, 2018
Short summary
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Hydrographic analysis in the Atlantic along 14.5° N and 24.5° N shows that between the periods of 1989/92 and 2013/15, the Antarctic Intermediate Water became warmer and saltier at 14.5° N, and that the Antarctic Bottom Water became lighter at both latitudes. By applying a box inverse model, the Atlantic Meridional Overturning Circulation (AMOC) was determined. Comparison among the inverse solution, GECCO2, RAPID, and MOVE shows that the AMOC has not significantly changed in the past 20 years.
Bogi Hansen, Turið Poulsen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, Svein Østerhus, Elin Darelius, Barbara Berx, Detlef Quadfasel, and Kerstin Jochumsen
Ocean Sci., 13, 873–888, https://doi.org/10.5194/os-13-873-2017, https://doi.org/10.5194/os-13-873-2017, 2017
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On its way towards the Arctic, an important branch of warm Atlantic water passes through the Faroese Channels, but, in spite of more than a century of investigations, the detailed flow pattern through this channel system has not been resolved. This has strong implications for estimates of oceanic heat transport towards the Arctic. Here, we combine observations from various sources, which together paint a coherent picture of the Atlantic water flow and heat transport through this channel system.
Bogi Hansen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, and Svein Østerhus
Ocean Sci., 12, 1205–1220, https://doi.org/10.5194/os-12-1205-2016, https://doi.org/10.5194/os-12-1205-2016, 2016
Short summary
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The Faroe Bank Channel is one of the main passages for the flow of cold dense water from the Arctic into the depths of the world ocean where it feeds the deep branch of the AMOC. Based on in situ measurements, we show that the volume transport of this flow has been stable from 1995 to 2015. The water has warmed, but salinity increase has maintained its high density. Thus, this branch of the AMOC did not weaken during the last 2 decades, but increased its heat transport into the deep ocean.
E. Frajka-Williams, C. S. Meinen, W. E. Johns, D. A. Smeed, A. Duchez, A. J. Lawrence, D. A. Cuthbertson, G. D. McCarthy, H. L. Bryden, M. O. Baringer, B. I. Moat, and D. Rayner
Ocean Sci., 12, 481–493, https://doi.org/10.5194/os-12-481-2016, https://doi.org/10.5194/os-12-481-2016, 2016
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The ocean meridional overturning circulation (MOC) is predicted by climate models to slow down in this century, resulting in reduced transport of heat northward to mid-latitudes. At 26° N, the Atlantic MOC has been measured continuously for the past decade (2004–2014). In this paper, we discuss the 10-year record of variability, identify the origins of the continued weakening of the circulation, and discuss high-frequency (subannual) compensation between transport components.
T. J. Sherwin, D. Aleynik, E. Dumont, and M. E. Inall
Ocean Sci., 11, 343–359, https://doi.org/10.5194/os-11-343-2015, https://doi.org/10.5194/os-11-343-2015, 2015
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The Rockall Trough feeds warm salty water to Polar regions and the European Shelf. Detailed observations from an underwater glider show that a) the meandering surface current field in the central trough is driven by deep eddies; b) chance circulations deflect the eastern slope current and warm the western side; c) and altimeter observations omit the mean flow in the narrow slope current. There are wider implications for satellite altimeter observations, ocean monitoring and ocean model results.
H. L. Bryden, B. A. King, G. D. McCarthy, and E. L. McDonagh
Ocean Sci., 10, 683–691, https://doi.org/10.5194/os-10-683-2014, https://doi.org/10.5194/os-10-683-2014, 2014
C. P. Atkinson, H. L. Bryden, S. A. Cunningham, and B. A. King
Ocean Sci., 8, 497–523, https://doi.org/10.5194/os-8-497-2012, https://doi.org/10.5194/os-8-497-2012, 2012
C. P. Atkinson, H. L. Bryden, J. J-M. Hirschi, and T. Kanzow
Ocean Sci., 6, 837–859, https://doi.org/10.5194/os-6-837-2010, https://doi.org/10.5194/os-6-837-2010, 2010
M. P. Chidichimo, T. Kanzow, S. A. Cunningham, W. E. Johns, and J. Marotzke
Ocean Sci., 6, 475–490, https://doi.org/10.5194/os-6-475-2010, https://doi.org/10.5194/os-6-475-2010, 2010
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Short summary
The main objective of the study is to analyze the export of carbon to the open ocean from the rich waters of the upwelling system of North Africa. South of the Canary Islands, permanent upwelling interacts with other physical processes impacting the main biogeochemical processes. Taking advantage of data from two cruises combined with the outputs of models, important conclusions from the differences observed between seasons are obtained, largely related to changes in the CVFZ in this area.
The main objective of the study is to analyze the export of carbon to the open ocean from the...
