Enhanced water mass mixing in Fram Strait in 2020 and elevated circulation timescales of Atlantic-derived waters in 2021 based on transient tracers I-129 and U-236

Scheiwiller, Marcel; Wefing, Anne-Marie; Pérez-Tribouillier, Habacuc; Vockenhuber, Christof; Dodd, Paul A.; Gwynn, Justin P.; Casacuberta, Núria

doi:10.5194/os-22-2779-2026

Articles | Volume 22, issue 5

https://doi.org/10.5194/os-22-2779-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/os-22-2779-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 22, issue 5

Research article

|

11 Sep 2026

Research article |

| 11 Sep 2026

Enhanced water mass mixing in Fram Strait in 2020 and elevated circulation timescales of Atlantic-derived waters in 2021 based on transient tracers I-129 and U-236

Marcel Scheiwiller, Anne-Marie Wefing, Habacuc Pérez-Tribouillier, Christof Vockenhuber, Paul A. Dodd, Justin P. Gwynn, and Núria Casacuberta

Data sets

CTD raw data files from POLARSTERN cruise PS100, link to tar file T. Kanzow and G. Rohardt https://doi.org/10.1594/PANGAEA.871701

Model code and software

I-129 and U-236 data from the Fram Strait in 2020 and 2021 Marcel Scheiwiller et al. https://doi.org/10.5281/zenodo.19387002

Short summary

We used man-made chemical markers to study how warm Atlantic origin water moves through the Arctic Ocean. Comparing Fram Strait observations from 2016 to 2021, we found stronger mixing in 2020 and longer transit times in 2021. This variability matters because these waters carry heat into the Arctic Ocean, intensifying its warming. Our findings help improve predictions of the Arctic Ocean climate response and its wider effects on ocean circulation.