Articles | Volume 22, issue 9
https://doi.org/10.5194/bg-22-2239-2025
© Author(s) 2025. 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-22-2239-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 May 2025
Research article |
| 13 May 2025
| 13 May 2025
Sea ice and mixed layer depth influence on nitrate depletion and associated isotopic effects in the Drake Passage–Weddell Sea region, Southern Ocean
Aymeric P. M. Servettaz
CORRESPONDING AUTHOR
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Institute of Arctic Climate and Environment Research, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Yuta Isaji
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Chisato Yoshikawa
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Yanghee Jang
Marine Radioactive Monitoring Group, Marine Environment Research Institute, Korea Marine Environment Management Corporation, Busan 49111, Republic of Korea
Boo-Keun Khim
CORRESPONDING AUTHOR
Department of Oceanography and Marine Research Institute, Pusan National University, Busan 46241, Republic of Korea
Yeongjun Ryu
Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA
Daniel M. Sigman
Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA
Nanako O. Ogawa
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Francisco J. Jiménez-Espejo
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
Instituto Andaluz de Ciencias de la Tierra, Spanish Research Council, 18100 Armilla, Granada, Spain
Naohiko Ohkouchi
Biogeochemistry Research Center, Japan Agency for Marine–Earth Science and Technology, Yokosuka, 237-0061 Kanagawa, Japan
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Short summary
Phytoplankton blooms occur after sea ice retreats in the Southern Ocean. In this study we investigate the influence of seasonal cycle of sea ice concentration on nitrate depletion, testing the hypothesis that meltwater release stabilizes the water column and favors nutrient utilization. We find that, at a regional scale, nitrate depletion and vertical mixing are weakly correlated with sea ice cycle. Nitrate depletion is rather linked to other oceanographic processes controlling mixing depth.
Phytoplankton blooms occur after sea ice retreats in the Southern Ocean. In this study we...
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