Changes in water mass composition and circulation in the central Arctic Ocean between 2011 and 2021 inferred from tracer observations

Wefing, Anne-Marie; Payne, Annabel; Scheiwiller, Marcel; Vockenhuber, Christof; Christl, Marcus; Tanhua, Toste; Casacuberta, Núria

doi:10.5194/os-21-3311-2025

Articles | Volume 21, issue 6

https://doi.org/10.5194/os-21-3311-2025

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

https://doi.org/10.5194/os-21-3311-2025

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

Articles | Volume 21, issue 6

Research article

|

04 Dec 2025

Research article |

| 04 Dec 2025

Changes in water mass composition and circulation in the central Arctic Ocean between 2011 and 2021 inferred from tracer observations

Anne-Marie Wefing, Annabel Payne, Marcel Scheiwiller, Christof Vockenhuber, Marcus Christl, Toste Tanhua, and Núria Casacuberta

Data sets

I-129 and U-236 data from the ODEN expedition SO21 for the Synoptic Arctic Survey Anne-Marie Wefing et al. https://doi.org/10.5281/zenodo.15056897

Physical Oceanography during ODEN expedition SO21 for the Synoptic Arctic Survey C. Heuzé et al. https://doi.org/10.1594/PANGAEA.951266

Physical Oceanography measured on bottle water samples during ODEN expedition SO21 for the Synoptic Arctic Survey C. Heuzé et al. https://doi.org/10.1594/PANGAEA.951264

The annual update GLODAPv2.2023: the global interior ocean biogeochemical data product (https://glodap.info/index.php/merged-and-adjusted-data-product-v2-2023/) S. K. Lauvset et al. https://doi.org/10.5194/essd-16-2047-2024

Short summary

Here we used the anthropogenic radionuclides I-129 and U-236 as tracers for Atlantic Water circulation in the Arctic Ocean. New data collected in 2021 allowed to assess the distribution of Atlantic Water and mixing with Pacific-origin water in the surface layer in that year. By using historical tracer data from 2011 to 2021, we looked into temporal changes of the circulation and found slightly older waters in the central Arctic Ocean in 2021 compared to 2015.