Articles | Volume 20, issue 2
https://doi.org/10.5194/os-20-475-2024
© Author(s) 2024. 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-20-475-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Apr 2024
Research article |
| 04 Apr 2024
| 04 Apr 2024
Exploring the relationship between sea ice and phytoplankton growth in the Weddell Gyre using satellite and Argo float data
Clara Celestine Douglas
CORRESPONDING AUTHOR
Ocean and Earth Science, University of Southampton, Southampton, UK
Ocean BioGeosciences, National Oceanography Centre, Southampton, UK
Nathan Briggs
Ocean BioGeosciences, National Oceanography Centre, Southampton, UK
Peter Brown
Ocean BioGeosciences, National Oceanography Centre, Southampton, UK
Graeme MacGilchrist
Atmospheric and Oceanic Science, Princeton University, Princeton, NJ, USA
School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK
Alberto Naveira Garabato
Ocean and Earth Science, University of Southampton, Southampton, UK
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Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 16, 2047–2072, https://doi.org/10.5194/essd-16-2047-2024, https://doi.org/10.5194/essd-16-2047-2024, 2024
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2023 is the fifth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1108 hydrographic cruises covering the world's oceans from 1972 to 2021.
Chuqing Zhang, Yingxu Wu, Peter J. Brown, David Stappard, Amavi N. Silva, and Toby Tyrrell
EGUsphere, https://doi.org/10.5194/egusphere-2023-3143, https://doi.org/10.5194/egusphere-2023-3143, 2024
Preprint archived
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In this study, we found that float-based pCO2 is overall high by systematically comparing ship-based pCO2 with float-based pCO2. This finding partly explains the apparent difference between the carbon fluxes calculated from the float data and other databases. It inspires further examination of the quality of the float pH data and the pCO2 calculation process.
Jennifer Cocks, Alessandro Silvano, Alice Marzocchi, Oana Dragomir, Noémie Schifano, Anna E. Hogg, and Alberto C. Naveira Garabato
EGUsphere, https://doi.org/10.5194/egusphere-2023-3050, https://doi.org/10.5194/egusphere-2023-3050, 2023
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Heat and freshwater fluxes in the Southern Ocean mediate global ocean circulation and abyssal ventilation. These fluxes manifest as changes in steric height: sea level anomalies from changes in ocean density. We compute the steric height anomaly of the Southern Ocean using satellite data and validate it against in-situ observations. We analyse interannual patterns, drawing links to climate variability, and discuss the effectiveness of the method, highlighting issues and suggesting improvements.
Christoph Heinze, Thorsten Blenckner, Peter Brown, Friederike Fröb, Anne Morée, Adrian L. New, Cara Nissen, Stefanie Rynders, Isabel Seguro, Yevgeny Aksenov, Yuri Artioli, Timothée Bourgeois, Friedrich Burger, Jonathan Buzan, B. B. Cael, Veli Çağlar Yumruktepe, Melissa Chierici, Christopher Danek, Ulf Dieckmann, Agneta Fransson, Thomas Frölicher, Giovanni Galli, Marion Gehlen, Aridane G. González, Melchor Gonzalez-Davila, Nicolas Gruber, Örjan Gustafsson, Judith Hauck, Mikko Heino, Stephanie Henson, Jenny Hieronymus, I. Emma Huertas, Fatma Jebri, Aurich Jeltsch-Thömmes, Fortunat Joos, Jaideep Joshi, Stephen Kelly, Nandini Menon, Precious Mongwe, Laurent Oziel, Sólveig Ólafsdottir, Julien Palmieri, Fiz F. Pérez, Rajamohanan Pillai Ranith, Juliano Ramanantsoa, Tilla Roy, Dagmara Rusiecka, J. Magdalena Santana Casiano, Yeray Santana-Falcón, Jörg Schwinger, Roland Séférian, Miriam Seifert, Anna Shchiptsova, Bablu Sinha, Christopher Somes, Reiner Steinfeldt, Dandan Tao, Jerry Tjiputra, Adam Ulfsbo, Christoph Völker, Tsuyoshi Wakamatsu, and Ying Ye
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-182, https://doi.org/10.5194/bg-2023-182, 2023
Preprint under review for BG
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For assessing the consequences of human-induced climate change for the marine realm, it is necessary to not only look at gradual changes but also at abrupt changes of environmental conditions. We summarise abrupt changes in ocean warming, acidification, and oxygen concentration as the key environmental factors for ecosystems. Taking these abrupt changes into account requires greenhouse gas emissions to be reduced to a larger extent than previously thought to limit respective damage.
Dani C. Jones, Maike Sonnewald, Shenjie Zhou, Ute Hausmann, Andrew J. S. Meijers, Isabella Rosso, Lars Boehme, Michael P. Meredith, and Alberto C. Naveira Garabato
Ocean Sci., 19, 857–885, https://doi.org/10.5194/os-19-857-2023, https://doi.org/10.5194/os-19-857-2023, 2023
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Machine learning is transforming oceanography. For example, unsupervised classification approaches help researchers identify underappreciated structures in ocean data, helping to generate new hypotheses. In this work, we use a type of unsupervised classification to identify structures in the temperature and salinity structure of the Weddell Gyre, which is an important region for global ocean circulation and for climate. We use our method to generate new ideas about mixing in the Weddell Gyre.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Simone Alin, Marta Álvarez, Kumiko Azetsu-Scott, Leticia Barbero, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Li-Qing Jiang, Steve D. Jones, Claire Lo Monaco, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 14, 5543–5572, https://doi.org/10.5194/essd-14-5543-2022, https://doi.org/10.5194/essd-14-5543-2022, 2022
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2022 is the fourth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1085 hydrographic cruises covering the world's oceans from 1972 to 2021.
Stefanie L. Ypma, Quinten Bohte, Alexander Forryan, Alberto C. Naveira Garabato, Andy Donnelly, and Erik van Sebille
Ocean Sci., 18, 1477–1490, https://doi.org/10.5194/os-18-1477-2022, https://doi.org/10.5194/os-18-1477-2022, 2022
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In this research we aim to improve cleanup efforts on the Galapagos Islands of marine plastic debris when resources are limited and the distribution of the plastic on shorelines is unknown. Using a network that describes the flow of macroplastic between the islands we have identified the most efficient cleanup locations, quantified the impact of targeting these locations and showed that shorelines where the plastic is unlikely to leave are likely efficient cleanup locations.
Charles E. Turner, Peter J. Brown, Kevin I. C. Oliver, and Elaine L. McDonagh
Ocean Sci., 18, 523–548, https://doi.org/10.5194/os-18-523-2022, https://doi.org/10.5194/os-18-523-2022, 2022
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Ocean heat and carbon content increase proportionately as the planet warms. However, circulation changes in response to changing heat content, redistributing preindustrial heat, carbon, and salinity fields. Redistribution leaves properties unchanged, so we may leverage our skill identifying preindustrial carbon in order to trace preindustrial heat and salinity field redistribution. Excess salinity opposes excess-temperature-induced density change, and redistribution grows continually.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Steven van Heuven, Mario Hoppema, Masao Ishii, Emil Jeansson, Sara Jutterström, Steve D. Jones, Maren K. Karlsen, Claire Lo Monaco, Patrick Michaelis, Akihiko Murata, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Anton Velo, Rik Wanninkhof, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 13, 5565–5589, https://doi.org/10.5194/essd-13-5565-2021, https://doi.org/10.5194/essd-13-5565-2021, 2021
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2021 is the third update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality control, including systematic evaluation of measurement biases. This version contains data from 989 hydrographic cruises covering the world's oceans from 1972 to 2020.
Are Olsen, Nico Lange, Robert M. Key, Toste Tanhua, Henry C. Bittig, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Steven van Heuven, Mario Hoppema, Masao Ishii, Emil Jeansson, Sara Jutterström, Camilla S. Landa, Siv K. Lauvset, Patrick Michaelis, Akihiko Murata, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Anton Velo, Rik Wanninkhof, and Ryan J. Woosley
Earth Syst. Sci. Data, 12, 3653–3678, https://doi.org/10.5194/essd-12-3653-2020, https://doi.org/10.5194/essd-12-3653-2020, 2020
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by chemical analysis of water bottle samples at scientific cruises. GLODAPv2.2020 is the second update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality control, including systematic evaluation of measurement biases. This version contains data from 946 hydrographic cruises covering the world's oceans from 1972 to 2019.
Pieter Demuynck, Toby Tyrrell, Alberto Naveira Garabato, Mark Christopher Moore, and Adrian Peter Martin
Biogeosciences, 17, 2289–2314, https://doi.org/10.5194/bg-17-2289-2020, https://doi.org/10.5194/bg-17-2289-2020, 2020
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The availability of macronutrients N and Si is of key importance to sustain life in the Southern Ocean. N and Si are available in abundance at the southern boundary of the Southern Ocean due to constant supply from the deep ocean. In the more northern regions of the Southern Ocean, a decline in macronutrient concentration is noticed, especially strong for Si rather than N. This paper uses a simplified biogeochemical model to investigate processes responsible for this decline in concentration.
Jan D. Zika, Jean-Baptiste Sallée, Andrew J. S. Meijers, Alberto C. Naveira-Garabato, Andrew J. Watson, Marie-Jose Messias, and Brian A. King
Ocean Sci., 16, 323–336, https://doi.org/10.5194/os-16-323-2020, https://doi.org/10.5194/os-16-323-2020, 2020
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The ocean can regulate climate by distributing heat and carbon dioxide into its interior. This work has resulted from a major experiment aimed at understanding how that distribution occurs. In the experiment an artificial tracer was released into the ocean. After release the tracer was tracked as it was distorted by ocean currents. Using novel methods we reveal how the tracer's distortions follow the movement of the underlying water masses in the ocean and we estimate the rate at which it mixes.
Alexander Forryan, Sheldon Bacon, Takamasa Tsubouchi, Sinhué Torres-Valdés, and Alberto C. Naveira Garabato
The Cryosphere, 13, 2111–2131, https://doi.org/10.5194/tc-13-2111-2019, https://doi.org/10.5194/tc-13-2111-2019, 2019
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We compare control volume and geochemical tracer-based methods of estimating the Arctic Ocean freshwater budget and find both methods in good agreement. Inconsistencies arise from the distinction between
Atlanticand
Pacificwaters in the geochemical calculations. The definition of Pacific waters is particularly problematic due to the non-conservative nature of the nutrients underpinning the definition and the low salinity characterizing waters entering the Arctic through Bering Strait.
M. Dolores Pérez-Hernández, Alonso Hernández-Guerra, Isis Comas-Rodríguez, Verónica M. Benítez-Barrios, Eugenio Fraile-Nuez, Josep L. Pelegrí, and Alberto C. Naveira Garabato
Ocean Sci., 13, 577–587, https://doi.org/10.5194/os-13-577-2017, https://doi.org/10.5194/os-13-577-2017, 2017
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The decadal differences between the ALBATROSS (April 1999) and MOC2-Austral (February 2010) hydrographic cruises are analyzed. Changes in the intermediate water masses beneath seem to be very sensitive to the wind conditions existing in their formation area. The Subantarctic Front is wider and weaker in 2010 than in 1999, while the Polar Front remains in the same position and strengthens.
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Short summary
We use data from satellites and robotic floats to assess what drives year-to-year variability in primary production in the Weddell Gyre. We find that the maximum area of ice-free water in the summer is important in determining the total primary production in the region but that areas that are ice free for longer than 120 d become nutrient limited. This has potential implications for ecosystem health in a warming world, where a decline in sea ice cover will affect total primary production.
We use data from satellites and robotic floats to assess what drives year-to-year variability in...
