Articles | Volume 16, issue 6
https://doi.org/10.5194/os-16-1347-2020
© 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-16-1347-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Nov 2020
Research article |
| 09 Nov 2020
| 09 Nov 2020
Influence of intraseasonal eastern boundary circulation variability on hydrography and biogeochemistry off Peru
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Marcus Dengler
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Stefan Sommer
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
David Clemens
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Sören Thomsen
LOCEAN-IPSL, IRD/CNRS/Sorbonnes Universites (UPMC)/MNHN, UMR 7159,
Paris, France
Gerd Krahmann
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Andrew W. Dale
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Eric P. Achterberg
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
Martin Visbeck
GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker
Weg 20, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
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Yu-Te Hsieh, Walter Geibert, E. Malcolm S. Woodward, Neil J. Wyatt, Maeve C. Lohan, Eric P. Achterberg, and Gideon M. Henderson
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Henrike Schmidt, Rena Czeschel, and Martin Visbeck
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Our investigations give detailed insight on the seasonally changing current system at intermediate depth in the Arabian Sea that is influenced by the monsoon. The changing currents influence the oxygen transport in the interior ocean and thus allow us to draw conclusions on the maintenance and seasonal variability of the upper part of the oxygen minimum zone in the Arabian Sea.
Ruifang C. Xie, Frédéric A. C. Le Moigne, Insa Rapp, Jan Lüdke, Beat Gasser, Marcus Dengler, Volker Liebetrau, and Eric P. Achterberg
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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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Alexandra N. Loginova, Andrew W. Dale, Frédéric A. C. Le Moigne, Sören Thomsen, Stefan Sommer, David Clemens, Klaus Wallmann, and Anja Engel
Biogeosciences, 17, 4663–4679, https://doi.org/10.5194/bg-17-4663-2020, https://doi.org/10.5194/bg-17-4663-2020, 2020
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We measured dissolved organic carbon (DOC), nitrogen (DON) and matter (DOM) optical properties in pore waters and near-bottom waters of the eastern tropical South Pacific off Peru. The difference between diffusion-driven and net fluxes of DOC and DON and qualitative changes in DOM optical properties suggested active microbial utilisation of the released DOM at the sediment–water interface. Our results suggest that the sediment release of DOM contributes to microbial processes in the area.
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Short summary
We analyse the intraseasonal variability of the alongshore circulation off Peru in early 2017, this circulation is very important for the supply of nutrients to the upwelling regime. The causes of this variability and its impact on the biogeochemistry are investigated. The poleward flow is strengthened during the observed time period, likely by a downwelling coastal trapped wave. The stronger current causes an increase in nitrate and reduces the deficit of fixed nitrogen relative to phosphorus.
We analyse the intraseasonal variability of the alongshore circulation off Peru in early 2017,...
