Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 97814 10.2205/2026es001081 asszdj ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Comparative Analysis of Eddies in Open Ocean and Marginal Ice Zone Using SWOT and Sentinel-1 Data Comparative Analysis of Eddies in Open Ocean and Marginal Ice Zone Using SWOT and Sentinel-1 Data https://orcid.org/0000-0001-6432-0722 Сандалюк Никита Валерьевич Sandalyuk Nikita Valer'evich nikitasandaliuk@gmail.com https://orcid.org/0000-0002-5765-8781 Хачатрян Эдуард Матевосович Khachatrian Eduard Matevosovich Московский физико-технический институт Россия The Moscow Institute of Physics and Technology Russian Federation Санкт-Петербургский государственный университет Россия Saint Petersburg State University Russian Federation Арктический университет Норвегии Норвегия UiT The Arctic University of Norway Norway GEOFEM Кипр GEOFEM Cyprus 20 02 2026 20 02 2026 26 1 ES1003 23 04 2025 05 11 2025 https://rjes.ru/en/nauka/article/97814/view

The new Surface Water and Ocean Topography (SWOT) mission, featuring unprecedented resolution and precision, represents a new era in satellite altimetry and exploration of ocean eddy dynamics. This paper provides a specific test case for the inter-comparison of eddy fields in the open ocean and the Marginal Ice Zone in the Fram Strait, utilizing Synthetic Aperture Radar (SAR) data and a complementary Level 3 product from the SWOT altimetry mission. We identified and matched 7 occurrences of open ocean eddies from both data sources. A crucial and anticipated finding is that the SSHA fields demonstrate clear capability in resolving small (up to 10 km) submesoscale eddies. The comparison of the SAR and backscattering coefficient from the SWOT unsmoothed fields for the Marginal Ice Zone region revealed a generally good agreement between both data types and can be used by the researchers as complementary data sources.

The new Surface Water and Ocean Topography (SWOT) mission, featuring unprecedented resolution and precision, represents a new era in satellite altimetry and exploration of ocean eddy dynamics. This paper provides a specific test case for the inter-comparison of eddy fields in the open ocean and the Marginal Ice Zone in the Fram Strait, utilizing Synthetic Aperture Radar (SAR) data and a complementary Level 3 product from the SWOT altimetry mission. We identified and matched 7 occurrences of open ocean eddies from both data sources. A crucial and anticipated finding is that the SSHA fields demonstrate clear capability in resolving small (up to 10 km) submesoscale eddies. The comparison of the SAR and backscattering coefficient from the SWOT unsmoothed fields for the Marginal Ice Zone region revealed a generally good agreement between both data types and can be used by the researchers as complementary data sources.

 SWOT Sentinel-1 SAR submesoscale-mesoscale eddies Fram Strait SWOT Sentinel-1 SAR submesoscale-mesoscale eddies Fram Strait This research was funded by the Moscow Institute of Physics and Technology under the State Agreement No. 075-03-2026-305 dated 16.01.2026, with the support of the grant of St. Petersburg University No. 129659573, and The Arctic University of Norway (UiT). The authors would also like to express their gratitude to the SWOT GitHub community for providing comprehensive tutorials on the processing of the SWOT data and to all members of the SWOT project. Sentinel-1 SAR data used in this study are publicly available on the Copernicus Data Space Ecosystem (https://dataspace.copernicus.eu/). The SWOT L2/L3 beta products are publicly available on the AVISO website (https://www. aviso.altimetry.fr). The L4 product from the merged altimetry missions containing ADT fields is publicly available at the Copernicus Marine Environment Monitoring Service portal (https://marine.copernicus.eu/). This research was funded by the Moscow Institute of Physics and Technology under the State Agreement No. 075-03-2026-305 dated 16.01.2026, with the support of the grant of St. Petersburg University No. 129659573, and The Arctic University of Norway (UiT). The authors would also like to express their gratitude to the SWOT GitHub community for providing comprehensive tutorials on the processing of the SWOT data and to all members of the SWOT project. Sentinel-1 SAR data used in this study are publicly available on the Copernicus Data Space Ecosystem (https://dataspace.copernicus.eu/). The SWOT L2/L3 beta products are publicly available on the AVISO website (https://www. aviso.altimetry.fr). The L4 product from the merged altimetry missions containing ADT fields is publicly available at the Copernicus Marine Environment Monitoring Service portal (https://marine.copernicus.eu/).

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