Sea ice and mixed layer depth influence on nitrate depletion and associated isotopic effects in the Drake Passage–Weddell Sea region, Southern Ocean

Servettaz, Aymeric P. M.; Isaji, Yuta; Yoshikawa, Chisato; Jang, Yanghee; Khim, Boo-Keun; Ryu, Yeongjun; Sigman, Daniel M.; Ogawa, Nanako O.; Jiménez-Espejo, Francisco J.; Ohkouchi, Naohiko

doi:https://doi.org/10.5194/bg-22-2239-2025

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.

https://doi.org/10.5194/bg-22-2239-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 22, issue 9

Research article

|

13 May 2025

Research article |

| 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, Yuta Isaji, Chisato Yoshikawa, Yanghee Jang, Boo-Keun Khim, Yeongjun Ryu, Daniel M. Sigman, Nanako O. Ogawa, Francisco J. Jiménez-Espejo, and Naohiko Ohkouchi

Data sets

Global Ocean Data Analysis Project version 2.2022 (GLODAPv2.2022) NCEI Accession 0257247 S. K. Lauvset et al. https://doi.org/10.25921/1f4w-0t92

Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) and Global Ocean Biogeochemistry (GO-BGC) Biogeochemical-Argo Float Data Archive K. S. Johnson et al. https://doi.org/10.6075/J0SJ1KT8

Global Sea Ice Concentration Climate Data Record v3.0 - Multimission OSI SAF https://doi.org/10.15770/EUM_SAF_OSI_0013

Global Sea Ice Concentration Interim Climate Data Record Release 3 - DMSP OSI SAF https://doi.org/10.15770/EUM_SAF_OSI_0014

Model code and software

Figure Notebook for Servettaz et al. EGUSPHERE-2024-3687 Aymeric P. M. Servettaz https://doi.org/10.5281/zenodo.14958219

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.