Articles | Volume 19, issue 3
https://doi.org/10.5194/bg-19-715-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-19-715-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Feb 2022
Research article |
| 07 Feb 2022
| 07 Feb 2022
Biogeochemical controls on ammonium accumulation in the surface layer of the Southern Ocean
Shantelle Smith
CORRESPONDING AUTHOR
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Katye E. Altieri
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Mhlangabezi Mdutyana
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Southern Ocean Carbon and Climate Observatory (SOCCO), CSIR,
Rosebank, Cape Town, South Africa
David R. Walker
Department of Conservation and Marine Sciences, Cape Peninsula
University of Technology, Cape Town, South Africa
Ruan G. Parrott
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Sedick Gallie
Department of Conservation and Marine Sciences, Cape Peninsula
University of Technology, Cape Town, South Africa
Kurt A. M. Spence
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Jessica M. Burger
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Sarah E. Fawcett
Department of Oceanography, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town, South Africa
Marine and Antarctic Research centre for Innovation and
Sustainability (MARIS), University of Cape Town, Cape Town, South Africa
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Short summary
Ammonium is a crucial yet poorly understood component of the Southern Ocean nitrogen cycle. We attribute our finding of consistently high ammonium concentrations in the winter mixed layer to limited ammonium consumption and sustained ammonium production, conditions under which the Southern Ocean becomes a source of carbon dioxide to the atmosphere. From similar data collected over an annual cycle, we propose a seasonal cycle for ammonium in shallow polar waters – a first for the Southern Ocean.
Ammonium is a crucial yet poorly understood component of the Southern Ocean nitrogen cycle. We...
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