Articles | Volume 17, issue 3
https://doi.org/10.5194/os-17-769-2021
© Author(s) 2021. 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-17-769-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Jun 2021
Research article |
| 11 Jun 2021
| 11 Jun 2021
Cape Verde Frontal Zone in summer 2017: lateral transports of mass, dissolved oxygen and inorganic nutrients
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
Ángel Rodríguez-Santana
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
Xosé Antón Álvarez-Salgado
Departamento de Oceanografía, CSIC Instituto de Investigacións Mariñas, Vigo, Spain
Bieito Fernández-Castro
Ocean and Earth Science, University of Southampton, Southampton, United Kingdom
María Dolores Gelado-Caballero
Departamento de Química, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Javier Arístegui
Instituto de Oceanografía y Cambio Global, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
Related authors
Nadia Burgoa, Francisco Machín, Ángeles Marrero-Díaz, Ángel Rodríguez-Santana, Antonio Martínez-Marrero, Javier Arístegui, and Carlos Manuel Duarte
Ocean Sci., 16, 483–511, https://doi.org/10.5194/os-16-483-2020, https://doi.org/10.5194/os-16-483-2020, 2020
Short summary
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.
Laura Marin-Samper, Javier Arístegui, Nauzet Hernández-Hernández, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2024-1776, https://doi.org/10.5194/egusphere-2024-1776, 2024
Short summary
Short summary
This study exposed a natural community to two non-CO2 equilibrated ocean alkalinity enhancement (OAE) deployments using different minerals. Adding alkalinity in this manner decreases dissolved CO2, essential for photosynthesis. While photosynthesis was not suppressed, bloom formation was delayed, potentially impacting marine food webs. The study emphasizes the need for further research on OAE without prior equilibration and its ecological implications
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, Joaquín Ortiz, Stephen D. Archer, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 21, 2859–2876, https://doi.org/10.5194/bg-21-2859-2024, https://doi.org/10.5194/bg-21-2859-2024, 2024
Short summary
Short summary
Our planet is facing a climate crisis. Scientists are working on innovative solutions that will aid in capturing the hard to abate emissions before it is too late. Exciting research reveals that ocean alkalinity enhancement, a key climate change mitigation strategy, does not harm phytoplankton, the cornerstone of marine ecosystems. Through meticulous study, we may have uncovered a positive relationship: up to a specific limit, enhancing ocean alkalinity boosts photosynthesis by certain species.
Tania Pereira-Vázquez, Borja Aguiar-González, Ángeles Marrero-Díaz, Marta Veny, and Ángel Rodríguez-Santana
EGUsphere, https://doi.org/10.5194/egusphere-2024-1166, https://doi.org/10.5194/egusphere-2024-1166, 2024
Preprint archived
Short summary
Short summary
We explore the seasonal dynamics of the Western Boundary Current System of the Weddell Sea Gyre using two ocean circulation models and observational data. Our analysis aims to evaluate the goodness of ocean reanalysis products in capturing these dynamics and to lay the groundwork for future interannual variability studies. We also report a previously unknown current, the Inner Weddell Current. Our results provide valuable insights for understanding a key region for the global ocean circulation.
Librada Ramírez, Leonardo J. Pozzo-Pirotta, Aja Trebec, Víctor Manzanares-Vázquez, José L. Díez, Javier Arístegui, Ulf Riebesell, Stephen D. Archer, and María Segovia
EGUsphere, https://doi.org/10.5194/egusphere-2024-847, https://doi.org/10.5194/egusphere-2024-847, 2024
Short summary
Short summary
We studied the potential effects of increasing ocean alkalinity on a natural plankton community in subtropical waters of the Atlantic near Gran Canaria, Spain. Alkalinity is the capacity of water to resist acidification and plankton are usually microscopic plants (phytoplankton) and animals (zooplankton), often less than 2,5 cm in length. This study suggests that increasing ocean alkalinity did not have a significant negative impact on the studied plankton community.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Zhibo Shao, Yangchun Xu, Hua Wang, Weicheng Luo, Lice Wang, Yuhong Huang, Nona Sheila R. Agawin, Ayaz Ahmed, Mar Benavides, Mikkel Bentzon-Tilia, Ilana Berman-Frank, Hugo Berthelot, Isabelle C. Biegala, Mariana B. Bif, Antonio Bode, Sophie Bonnet, Deborah A. Bronk, Mark V. Brown, Lisa Campbell, Douglas G. Capone, Edward J. Carpenter, Nicolas Cassar, Bonnie X. Chang, Dreux Chappell, Yuh-ling Lee Chen, Matthew J. Church, Francisco M. Cornejo-Castillo, Amália Maria Sacilotto Detoni, Scott C. Doney, Cecile Dupouy, Marta Estrada, Camila Fernandez, Bieito Fernández-Castro, Debany Fonseca-Batista, Rachel A. Foster, Ken Furuya, Nicole Garcia, Kanji Goto, Jesús Gago, Mary R. Gradoville, M. Robert Hamersley, Britt A. Henke, Cora Hörstmann, Amal Jayakumar, Zhibing Jiang, Shuh-Ji Kao, David M. Karl, Leila R. Kittu, Angela N. Knapp, Sanjeev Kumar, Julie LaRoche, Hongbin Liu, Jiaxing Liu, Caroline Lory, Carolin R. Löscher, Emilio Marañón, Lauren F. Messer, Matthew M. Mills, Wiebke Mohr, Pia H. Moisander, Claire Mahaffey, Robert Moore, Beatriz Mouriño-Carballido, Margaret R. Mulholland, Shin-ichiro Nakaoka, Joseph A. Needoba, Eric J. Raes, Eyal Rahav, Teodoro Ramírez-Cárdenas, Christian Furbo Reeder, Lasse Riemann, Virginie Riou, Julie C. Robidart, Vedula V. S. S. Sarma, Takuya Sato, Himanshu Saxena, Corday Selden, Justin R. Seymour, Dalin Shi, Takuhei Shiozaki, Arvind Singh, Rachel E. Sipler, Jun Sun, Koji Suzuki, Kazutaka Takahashi, Yehui Tan, Weiyi Tang, Jean-Éric Tremblay, Kendra Turk-Kubo, Zuozhu Wen, Angelicque E. White, Samuel T. Wilson, Takashi Yoshida, Jonathan P. Zehr, Run Zhang, Yao Zhang, and Ya-Wei Luo
Earth Syst. Sci. Data, 15, 3673–3709, https://doi.org/10.5194/essd-15-3673-2023, https://doi.org/10.5194/essd-15-3673-2023, 2023
Short summary
Short summary
N2 fixation by marine diazotrophs is an important bioavailable N source to the global ocean. This updated global oceanic diazotroph database increases the number of in situ measurements of N2 fixation rates, diazotrophic cell abundances, and nifH gene copy abundances by 184 %, 86 %, and 809 %, respectively. Using the updated database, the global marine N2 fixation rate is estimated at 223 ± 30 Tg N yr−1, which triplicates that using the original database.
Kristian Spilling, Jonna Piiparinen, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Maria T. Camarena-Gómez, Elisabeth von der Esch, Martin A. Fischer, Markel Gómez-Letona, Nauzet Hernández-Hernández, Judith Meyer, Ruth A. Schmitz, and Ulf Riebesell
Biogeosciences, 20, 1605–1619, https://doi.org/10.5194/bg-20-1605-2023, https://doi.org/10.5194/bg-20-1605-2023, 2023
Short summary
Short summary
We carried out an enclosure experiment using surface water off Peru with different additions of oxygen minimum zone water. In this paper, we report on enzyme activity and provide data on the decomposition of organic matter. We found very high activity with respect to an enzyme breaking down protein, suggesting that this is important for nutrient recycling both at present and in the future ocean.
Jens Hartmann, Niels Suitner, Carl Lim, Julieta Schneider, Laura Marín-Samper, Javier Arístegui, Phil Renforth, Jan Taucher, and Ulf Riebesell
Biogeosciences, 20, 781–802, https://doi.org/10.5194/bg-20-781-2023, https://doi.org/10.5194/bg-20-781-2023, 2023
Short summary
Short summary
CO2 can be stored in the ocean via increasing alkalinity of ocean water. Alkalinity can be created via dissolution of alkaline materials, like limestone or soda. Presented research studies boundaries for increasing alkalinity in seawater. The best way to increase alkalinity was found using an equilibrated solution, for example as produced from reactors. Adding particles for dissolution into seawater on the other hand produces the risk of losing alkalinity and degassing of CO2 to the atmosphere.
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
Short summary
Short summary
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.
Pascal Perolo, Bieito Fernández Castro, Nicolas Escoffier, Thibault Lambert, Damien Bouffard, and Marie-Elodie Perga
Earth Syst. Dynam., 12, 1169–1189, https://doi.org/10.5194/esd-12-1169-2021, https://doi.org/10.5194/esd-12-1169-2021, 2021
Short summary
Short summary
Wind blowing over the ocean creates waves that, by increasing the level of turbulence, promote gas exchange at the air–water interface. In this study, for the first time, we measured enhanced gas exchanges by wind-induced waves at the surface of a large lake. We adapted an ocean-based model to account for the effect of surface waves on gas exchange in lakes. We finally show that intense wind events with surface waves contribute disproportionately to the annual CO2 gas flux in a large lake.
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
Biogeosciences, 18, 4305–4320, https://doi.org/10.5194/bg-18-4305-2021, https://doi.org/10.5194/bg-18-4305-2021, 2021
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Nadia Burgoa, Francisco Machín, Ángeles Marrero-Díaz, Ángel Rodríguez-Santana, Antonio Martínez-Marrero, Javier Arístegui, and Carlos Manuel Duarte
Ocean Sci., 16, 483–511, https://doi.org/10.5194/os-16-483-2020, https://doi.org/10.5194/os-16-483-2020, 2020
Short summary
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.
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
Short summary
Short summary
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.
Jose Luis Otero-Ferrer, Pedro Cermeño, Antonio Bode, Bieito Fernández-Castro, Josep M. Gasol, Xosé Anxelu G. Morán, Emilio Marañon, Victor Moreira-Coello, Marta M. Varela, Marina Villamaña, and Beatriz Mouriño-Carballido
Biogeosciences, 15, 6199–6220, https://doi.org/10.5194/bg-15-6199-2018, https://doi.org/10.5194/bg-15-6199-2018, 2018
Short summary
Short summary
The effect of inorganic nutrients on planktonic assemblages has been traditionally assessed by looking at concentrations rather than fluxes of nutrient supply. However, in near-steady-state systems such as subtropical gyres, nitrate concentrations are kept close to the detection limit due to phytoplankton uptake. Our results, based on direct measurements of nitrate diffusive fluxes, support the key role of nitrate supply in controlling the structure of marine picoplankton communities.
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
Short summary
Short summary
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.
Cited articles
Anderson, L. A. and Sarmiento, J. L.: Redfield ratios of remineralization
determined by nutrient data analysis, Global Biogeochem. Cy., 8,
65–80, 1994. a
von Appen, W.-J., Strass, V. H., Bracher, A., Xi, H., Hörstmann, C., Iversen, M. H., and Waite, A. M.: High-resolution physical–biogeochemical structure of a filament and an eddy of upwelled water off northwest Africa, Ocean Sci., 16, 253–270, https://doi.org/10.5194/os-16-253-2020, 2020. a, b
Barceló-Llull, B., Sangrà, P., Pallàs-Sanz, E., Barton, E. D.,
Estrada-Allis, S. N., Martínez-Marrero, A., Aguiar-González, B.,
Grisolía, D., Gordo, C., Rodríguez-Santana, Á., Marrero-Díaz, Á., and Arístegui, J.: Anatomy
of a subtropical intrathermocline eddy, Deep-Sea Res. Pt. I, 124, 126–139, 2017. a
Barton, E.: Meanders, eddies and intrusions in the thermohaline front off
Northwest Africa, Oceanol. Acta, 10, 267–283, 1987. a
Barton, E. D.: The poleward undercurrent on the eastern boundary
of the subtropical North Atlantic, Poleward flows along eastern
ocean boundaries, Springer, New York, NY, 82–95, 1989. a
Benazzouz, A., Pelegrí, J. L., Demarcq, H., Machín, F., Mason, E.,
Orbi, A., Peña-Izquierdo, J., and Soumia, M.: On the temporal memory
of coastal upwelling off NW Africa, J. Geophys. Res. C, 119, 6356–6380, https://doi.org/10.1002/2013JC009559, 2014b. a
Bentamy, A. and Fillon, D. C.: Gridded surface wind fields from Metop/ASCAT
measurements, Int. J. Remote Sens., 33, 1729–1754, 2012. a
Brandt, P., Bange, H. W., Banyte, D., Dengler, M., Didwischus, S.-H., Fischer, T., Greatbatch, R. J., Hahn, J., Kanzow, T., Karstensen, J., Körtzinger, A., Krahmann, G., Schmidtko, S., Stramma, L., Tanhua, T., and Visbeck, M.: On the role of circulation and mixing in the ventilation of oxygen minimum zones with a focus on the eastern tropical North Atlantic, Biogeosciences, 12, 489–512, https://doi.org/10.5194/bg-12-489-2015, 2015. a
Broecker, W.: “NO”A conservative-mass tracer, Earth Planet Sc. Lett.,
23, 100–107, 1974. a
Burgoa, N., Machín, F., Marrero-Díaz, A., Rodríguez-Santana, A.,
Martínez-Marrero, A., Arístegui, J., and Duarte, C. M.: Mass,
nutrients and dissolved organic carbon (DOC) lateral transports off northwest
Africa during fall 2002 and spring 2003, Ocean Sci., 16, 483–511,
https://doi.org/10.5194/os-16-483-2020, 2020. a, b, c, d, e
Capet, X., McWilliams, J. C., Molemaker, M. J., and Shchepetkin, A.: Mesoscale
to submesoscale transition in the California Current System. Part II: Frontal
processes, J. Phys. Oceanogr., 38, 44–64, 2008. a
Castellanos, P., Pelegrí, J. L., Campos, E. J., Rosell-Fieschi, M., and
Gasser, M.: Response of the surface tropical Atlantic Ocean to wind forcing,
Prog. Oceanogr., 134, 271–292, 2015. a
Ekman, V. W.: Über Horizontalzirkulation bei winderzeugten
Meeresströmungen, R. Friedländer & Sohn, Berlin, 1923. a
Emery, W. J.: Water types and water masses, Enc. Ocean Sci., 6,
3179–3187, 2001. a
Fu, Y., Karstensen, J., and Brandt, P.: 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, Ocean Sci., 14, 589–616,
https://doi.org/10.5194/os-14-589-2018, 2018. a
Gabric, A. J., Garcia, L., Van Camp, L., Nykjaer, L., Eifler, W., and Schrimpf,
W.: Offshore export of shelf production in the Cape Blanc (Mauritania) giant
filament as derived from coastal zone color scanner imagery, J.
Geophys. Res.-Ocean., 98, 4697–4712, 1993. a
Ganachaud, A.: Large-scale mass transports, water mass formation, and
diffusivities estimated from World Ocean Circulation Experiment (WOCE)
hydrographic data, J. Geophys. Res., 108, 3213,
https://doi.org/10.1029/2002JC001565, 2003a. a, b
Ganachaud, A. S.: Large Scale Oceanic Circulation and Fluxes of Freshwater,
Heat, Nutrients and Oxygen, Ph.D. thesis, Massachusetts Institute of
Technology and Woods Hole Oceanographic Institution, 106–124, https://doi.org/10.1575/1912/4130,
1999. a, b, c, d
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O. K.,
Zweng, M. M., Reagan, J. R., and Johnson, D. R.: World Ocean Atlas 2013,
Vol. 3, Dissolved Oxygen, Apparent Oxygen Utilization, and Oxygen
Saturation, NOAA Atlas NESDIS 75, p. 27, 2014a. a
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O. K.,
Zweng, M. M., Reagan, J. R., and Johnson, D. R.: World Ocean Atlas 2013,
Volume 4: Dissolved Inorganic Nutrients (phosphate, nitrate, silicate), NOAA
Atlas NESDIS 76, p. 25, 2014b. a
Grasshoff, K., Ehrhardt, M., and Kremling, K.: Determination of nutrients,
Methods of Seawater Analysis, WILEY-VCH, Germany, 159–228, 1999. a
Hempel, G.: The Canary Current:Studies of an Upwelling System, A Symposium
held in Las Palmas, 11–14 April 1978, Secretariat of the International
Council for the Exploration of the Sea, Copenhagen, 180, ISSN 0074-4336, 1982. a
Hernández-Guerra, A., Fraile-Nuez, E., López-Laatzen, F.,
Martínez, A., Parrilla, G., and Vélez-Belchí, P.: Canary
Current and North Equatorial Current from an inverse box model, J.
Geophys. Res.-Ocean., 110, 1–16, https://doi.org/10.1029/2005JC003032, 2005. a, b
Hernández-Guerra, A., Espino-Falcón, E., Vélez-Belchí,
P., Pérez-Hernández, M. D., Martínez-Marrero, A., and Cana,
L.: Recirculation of the Canary Current in fall 2014, J. Mar.
Syst., 174, 25–39, https://doi.org/10.1016/j.jmarsys.2017.04.002, 2017. a
Hughes, P. and Barton, E. D.: Stratification and water mass structure in the
upwelling area off northwest Africa in April/May 1969, Deep-Sea Res.
Oceanogr. Abstracts, 21, 611–628, https://doi.org/10.1016/0011-7471(74)90046-1, 1974. a
IOC, SCOR, and IAPSO: The international thermodynamic equation of seawater – 2010: Calculation and
use of thermodynamic properties. Intergovernmental Oceanographic Commission, Manuals and Guides No.
56, UNESCO (English), 196 pp., 2010. a
Jackett, D. R. and McDougall, T. J.: A Neutral Density Variable for the
World's Oceans, J. Phys. Oceanogr., 27, 237–263, 1997. a
Karstensen, J. and Tomczak, M.: Age determination of mixed water masses using
CFC and oxygen data, J. Geophys. Res.-Ocean., 103,
18599–18609, 1998. a
Karstensen, J., Stramma, L., and Visbeck, M.: Oxygen minimum zones in the
eastern tropical Atlantic and Pacific oceans, Prog. Oceanogr., 77,
331–350, 2008. a
Kawase, M. and Sarmiento, J. L.: Nutrients in the Atlantic thermocline, J. Geophys. Res.-Ocean., 90, 8961–8979, 1985. a
Lázaro, C., Fernandes, M. J., Santos, A. M. P., and Oliveira, P.:
Seasonal and interannual variability of surface circulation in the Cape
Verde region from 8 years of merged T/P and ERS-2 altimeter data, Remote
Sens. Environ., 98, 45–62, https://doi.org/10.1016/j.rse.2005.06.005, 2005. a
Locarnini, R. A., Mishonov, A. V., Antonov, J. I., Boyer, T. P., Garcia, H. E.,
Baranova, O. K., Zweng, M. M., Paver, C. R., Reagan, J. R., Johnson, D. R.,
Hamilton, M., and Seidov, D.: World Ocean Atlas 2013, Volume 1: Temperature,
NOAA Atlas NESDIS 73, p. 44, 2013. a
Locarnini, R. A., Mishonov, A. V., Baranova, O. K., Boyer, T. P., Zweng, M. M.,
Garcia, H. E., Reagan, J. R., Seidov, D., Weathers, K., Paver, C. R., and
Smolyar, I.: World Ocean Atlas 2018, Volume 1: Temperature, NOAA Atlas
NESDIS, 81, 52 pp., 2018. a
Lønborg, C. and Álvarez-Salgado, X. A.: Tracing dissolved organic matter
cycling in the eastern boundary of the temperate North Atlantic using
absorption and fluorescence spectroscopy, Deep-Sea Res. Pt. I, 85, 35–46, 2014. a
Lovecchio, E., Gruber, N., and Münnich, M.: Mesoscale contribution to the long-range offshore transport of organic carbon from the Canary Upwelling System to the open North Atlantic, Biogeosciences, 15, 5061–5091, https://doi.org/10.5194/bg-15-5061-2018, 2018. a
Luyten, J., Pedlosky, J., and Stommel, H.: The ventilated thermocline, J. Phys. Oceanogr., 13, 292–309, 1983. a
Machín, F.: Variabilidad espacio temporal de la Corriente de Canarias,
del afloramiento costero al noroeste de África y de los intercambios
atmósfera-océano de calor y agua dulce, Ph.D. thesis, Universidad de Las
Palmas de Gran Canaria, available at: http://hdl.handle.net/10553/2118 (last access: 7 June 2021), 2003. a, b, c
Machín, F., Pelegrí, J. L., Fraile-Nuez, E.,
Vélez-Belchí, P., López-Laatzen, F., and
Hernández-Guerra, A.: Seasonal Flow Reversals of Intermediate Waters
in the Canary Current System East of the Canary Islands, J. Phys.
Oceanogr., 40, 1902–1909, https://doi.org/10.1175/2010JPO4320.1, 2010. a, b, c
Martel, F. and Wunsch, C.: The North Atlantic Circulation in the Early
1980s-An Estimate from Inversion of a Finite-Difference Model, J.
Phys. Oceanogr., 23, 898–924, 1993. a
Martínez-Marrero, A., Rodríguez-Santana, A.,
Hernández-Guerra, A., Fraile-Nuez, E., López-Laatzen, F.,
Vélez-Belchí, P., and Parrilla, G.: Distribution of water masses
and diapycnal mixing in the Cape Verde Frontal Zone, Geophys. Res.
Lett., 35, 0–4, https://doi.org/10.1029/2008GL033229, 2008. a, b, c, d
MATLAB: version R2019b, The MathWorks Inc., Natick, Massachusetts,
available at: https://www.mathworks.com/products/matlab.html (last access: 30 March 2021), 2019. a
McDougall, T. J. and Barker, P. M.: Getting started with TEOS-10 and the Gibbs
Seawater (GSW) oceanographic toolbox, SCOR/IAPSO WG, 127, 1–28, 2011. a
McDougall, T. J., Jackett, D. R., Millero, F. J., Pawlowicz, R., and Barker, P. M.: A global algorithm for estimating Absolute Salinity, Ocean Sci., 8, 1123–1134, https://doi.org/10.5194/os-8-1123-2012, 2012. a
Meunier, T., Barton, E. D., Barreiro, B., and Torres, R.: Upwelling filaments
off Cap Blanc: Interaction of the NW African upwelling current and the Cape
Verde frontal zone eddy field?, J. Geophys. Res.-Ocean., 117, https://doi.org/10.1029/2012JC007905,
2012. a, b
Paillet, J. and Mercier, H.: An inverse model of the eastern North Atlantic
general circulation and thermocline ventilation, Deep-Sea Res. Pt. I, 44, 1293–1328,
https://doi.org/10.1016/S0967-0637(97)00019-8, 1997. a
Pastor, M. V., Palter, J. B., Pelegrí, J. L., and Dunne, J. P.: Physical
drivers of interannual chlorophyll variability in the eastern subtropical
North Atlantic, J. Geophys. Res.-Ocean., 118, 3871–3886,
https://doi.org/10.1002/jgrc.20254, 2013. a, b
Pelegrí, J. L. and Benazzouz, A.: Oceanographic and biological features
in the Canary Current Large Marine Ecosystem, Chap. 3.4, Coastal Upwelling
off north-west Africa, IOC Technical Series, 115, 2015a. a
Pelegrí, J. L., Arístegui, J., Cana, L.,
González-Dávila, M., Hernández-Guerra, A.,
Hernández-León, S., Marrero-Díaz, A., Montero, M. F.,
Sangrà, P., and Santana-Casiano, M.: Coupling between the open ocean
and the coastal upwelling region off northwest Africa: Water recirculation
and offshore pumping of organic matter, J. Mar. Syst. 54,
3–37, https://doi.org/10.1016/j.jmarsys.2004.07.003, 2005. a
Pelegrí, J. L., Marrero-Díaz, A., and Ratsimandresy, A. W.:
Nutrient irrigation of the North Atlantic, Prog. Oceanogr., 70,
366–406, https://doi.org/10.1016/j.pocean.2006.03.018, 2006. a, b
Pelegrí, J. L., Peña-Izquierdo, J., Machín, F., Meiners, C., and
Presas-Navarro, C.: Deep-Sea Ecosystems Off Mauritania, Chapter 3,
Oceanography of the Cape Verde Basin and Mauritanian Slope Waters, Springer, 119–153,
https://doi.org/10.1007/978-94-024-1023-5_3, 2017. a, b, c
Peña-Izquierdo, J., Pelegrí, J. L., Pastor, M. V., Castellanos, P.,
Emelianov, M., Gasser, M., Salvador, J., and Vázquez-Domínguez,
E.: The continental slope current system between Cape Verde and the Canary
Islands, Sci. Mar., 76, 65–78, https://doi.org/10.3989/scimar.03607.18C, 2012. a, b
Pérez, F. F., Mintrop, L., Llinás, O., Glez-Dávila, M., Castro, C. G.,
Alvarez, M., Körtzinger, A., Santana-Casiano, M., Rueda, M. J., and Ríos,
A. F.: Mixing analysis of nutrients, oxygen and inorganic carbon in the
Canary Islands region, J. Mar. Syst., 28, 183–201,
https://doi.org/10.1016/S0924-7963(01)00003-3, 2001. a
Pérez-Hernández, M. D., Hernández-Guerra, A., Fraile-Nuez,
E., Comas-Rodríguez, I., Benítez-Barrios, V. M.,
Domínguez-Yanes, J. F., Vélez-Belchí, P., and De Armas,
D.: The source of the Canary current in fall 2009, J. Geophys.
Res.-Ocean., 118, 2874–2891, https://doi.org/10.1002/jgrc.20227, 2013. a
Pérez-Rodríguez, P., Pelegrí, J. L., and Marrero-Díaz,
A.: Dynamical characteristics of the Cape Verde frontal zone, Sci.
Mar., 65, 241–250, https://doi.org/10.3989/scimar.2001.65s1241, 2001. a
Powers, J. G., Klemp, J. B., Skamarock, W. C., Davis, C. A., Dudhia, J., Gill,
D. O., Coen, J. L., Gochis, D. J., Ahmadov, R., Peckham, S. E., Grell, G. A., Michalakes, J., Trahan, S., Beniamin, S. G., Alexander, C. R., Dimego, G. J., Wang, W., Schwartz, C. S., Romine, G. S., Liu, Z., Snyder C., Chen, F., Barlage, M. J., Yu, W., and Duda, M. G.: The
weather research and forecasting model: Overview, system efforts, and future
directions, Bull. Am. Meteorol. Soc., 98, 1717–1737,
2017. a
Sangrà, P., Pascual, A., Rodríguez-Santana, Á., Machín,
F., Mason, E., McWilliams, J. C., Pelegrí, J. L., Dong, C., Rubio, A.,
Arístegui, J., Marrero-Díaz, Á., Hernández-Guerra,
A., Martínez-Marrero, A., and Auladell, M.: The Canary Eddy Corridor:
A major pathway for long-lived eddies in the subtropical North Atlantic,
Deep-Sea Res. Pt. I, 56, 2100–2114,
https://doi.org/10.1016/j.dsr.2009.08.008, 2009. a, b
Smith, W. H. F. and Sandwell, D. T.: Global Sea Floor Topography from Satellite
Altimetry and Ship Depth Soundings, Science, 277, 1956–1962,
https://doi.org/10.1126/science.277.5334.1956, 1997. a
Stramma, L.: Geostrophic transport in the warm water sphere of the eastern
subtropical North Atlantic, J. Mar. Res., 42, 537–558,
https://doi.org/10.1357/002224084788506022, 1984. a
Stramma, L. and Siedler, G.: Seasonal changes in the North Atlantic subtropical
gyre, J. Geophys. Res.-Ocean., 93, 8111–8118, 1988. a
Thomas, L. N.: Formation of intrathermocline eddies at ocean fronts by
wind-driven destruction of potential vorticity, Dynam. Atmos.
Ocean., 45, 252–273, 2008. a
Thomsen, S., Karstensen, J., Kiko, R., Krahmann, G., Dengler, M., and Engel, A.: Remote and local drivers of oxygen and nitrate variability in the shallow oxygen minimum zone off Mauritania in June 2014, Biogeosciences, 16, 979–998, https://doi.org/10.5194/bg-16-979-2019, 2019.
a, b
Tomczak, M.: The CINECA experience, Mar. Policy, 3, 59–65,
https://doi.org/10.1016/0308-597X(79)90040-X, 1979. a
Troupin, C., Barth, A., Sirjacobs, D., Ouberdous, M., Brankart, J.-M.,
Brasseur, P., Rixen, M., Alvera-Azcárate, A., Belounis, M., Capet, A.,
Lenartz, F., Toussaint, M.-E., and Beckers, J.-M.: Generation of analysis and consistent error fields using the Data
Interpolating Variational Analysis (DIVA), Ocean Modell., 52, 90–101,
2012. a
UNESCO: The international system of units (SI) in oceanography, Technical Paper
in Marine Science, 45, 1–124, 1985. a
Volkov, D. L., Lee, T., and Fu, L.-L.: Eddy-induced meridional heat transport
in the ocean, Geophys. Res. Lett., 35, https://doi.org/10.1029/2008GL035490, 2008. a
Wanninkhof, R.: Relationship between wind speed and gas exchange over the ocean
revisited, Limnol. Oceanogr.-Method., 12, 351–362, 2014. a
Wunsch, C.: North Atlantic general circulation west of 50∘W determined
by inverse methods, Rev. Geophys., 16, 583–620, 1978. a
Zhang, Z., Wang, W., and Qiu, B.: Oceanic mass transport by mesoscale eddies,
Science, 345, 322–324, 2014. a
Zweng, M. M., Reagan, J. R., Antonov, J. I., Locarnini, R. A., Mishonov, A. V.,
Boyer, T. P., Garcia, H. E., Baranova, O. K., Johnson, D. R., Seidov, D., and
Biddle, M. M.: World Ocean Atlas 2013, Volume 2: Salinity, NOAA Atlas NESDIS
74, p. 39, 2013. a
Zweng, M. M., Reagan, J. R., Seidov, D., Boyer, T. P., Locarnini, R. A.,
Garcia, H. E., Mishonov, A. V., Baranova, O. K., Weathers, K., Paver, C. R.,
and Smolyar, I.: World Ocean Atlas 2018, Vol. 2, Salinity, NOAA Atlas
NESDIS, 82, 50 pp., 2018. a
Short summary
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.
The circulation patterns in the confluence of the North Atlantic subtropical and tropical gyres...
