Arctic sea ice predictability on daily-to-weekly timescales: sensitivity to initial positional errors under different rheology formulations

Fiol, Lohenn; Leroux, Stephanie; Rampal, Pierre; Brankart, Jean-Michel

doi:10.5194/tc-20-4655-2026

Articles | Volume 20, issue 8

https://doi.org/10.5194/tc-20-4655-2026

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

https://doi.org/10.5194/tc-20-4655-2026

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

Articles | Volume 20, issue 8

Research article

|

24 Aug 2026

Research article |

| 24 Aug 2026

Arctic sea ice predictability on daily-to-weekly timescales: sensitivity to initial positional errors under different rheology formulations

Lohenn Fiol, Stephanie Leroux, Pierre Rampal, and Jean-Michel Brankart

Data sets

Lagrangian trajectory dataset used in Fiol et al. 2026 (v1.0) L. Fiol et al. https://doi.org/10.5281/zenodo.17897059

Model code and software

lu-simulator (v1.0) J.-M. Brankart and S. Leroux https://doi.org/10.5281/zenodo.17896830

sitrack: 1.1 L. Brodeau https://doi.org/10.5281/zenodo.17942142

Notebooks of the figures of Fiol et al. 2026 (v1.0) L. Fiol https://doi.org/10.5281/zenodo.17896832

Short summary

We examine how uncertainty in the initial position of sea ice features (leads, ridges), affects daily-to-weekly winter sea-ice forecasts. Using ensemble simulations with a sea ice–ocean model, we compare two formulations of sea ice mechanics. We show that pack-ice dynamics are highly sensitive to this choice: one formulation strongly amplifies small initial errors, while the other damps them. Our results highlight the need for ensemble forecasts to capture uncertainty and risks in the Arctic.