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arXiv · 2601.07392

OceanSAR-2: A Universal Feature Extractor for SAR Ocean Observation

Alexandre Tuel·Thomas Kerdreux·Quentin Febvre·Alexis Mouche·Antoine Grouazel·Jean-Renaud Miadana·Antoine Audras·Chen Wang·Bertrand Chapron
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Abstract

We present OceanSAR-2, the second generation of our foundation model for SAR-based ocean observation. Building on our earlier release, which pioneered self-supervised learning on Sentinel-1 Wave Mode data, OceanSAR-2 relies on improved SSL training and dynamic data curation strategies, which enhances performance while reducing training cost. OceanSAR-2 demonstrates strong transfer performance across downstream tasks, including geophysical pattern classification, ocean surface wind vector and significant wave height estimation, and iceberg detection. We release standardized benchmark datasets, providing a foundation for systematic evaluation and advancement of SAR models for ocean applications.

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Alexandre Tuel, Thomas Kerdreux, Quentin Febvre, Alexis Mouche, Antoine Grouazel, Jean-Renaud Miadana, Antoine Audras, Chen Wang, Bertrand Chapron. 2026-01-12. OceanSAR-2: A Universal Feature Extractor for SAR Ocean Observation. https://arxiv.org/abs/2601.07392

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