Arctic sea ice has undergone a rapid decrease in extent, significant thinning, and a reduction in multiyear ice over recent decades, impacting the region's climate, human activities, and ecosystems. The rate and pattern of sea ice decline vary by region and season, leading to a gradual shift from consolidated to more seasonal ice conditions.

In a recent paper, Francesco Cocetta et al. examine the spatiotemporal variability of the Arctic sea ice area and thickness using the Global ocean Reanalysis Ensemble Product (GREP), which is produced and disseminated by the Copernicus Marine Service. Their findings indicate that GREP is a valuable tool for deepening our understanding of Arctic sea ice, especially as warming trends suggest an approaching transition to ice-free Arctic summers.

The study demonstrates that GREP sea ice variables are as reliable as satellite estimates and regional sea ice reanalyses in describing the marginal ice zone (MIZ), which is expected to become predominant in the future Arctic. Given the high variability of marginal conditions, the authors highlight the need for enhanced simulation capabilities to properly capture MIZ trends and responses to external forces. This study is also especially relevant as reanalyses are increasingly used to train machine learning models for predictions and climate-related applications.


Assessing the representation of Arctic sea ice and the marginal ice zone in ocean–sea ice reanalyses
Cocetta, F., Zampieri, L., Selivanova, J., and Iovino, D.
(2024)The Cryosphere, 18, 4687–4702, https://doi.org/10.5194/tc-18-4687-2024