Articles | Volume 22, issue 4
https://doi.org/10.5194/os-22-2267-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-22-2267-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Documenting the 2015–2017 freshening of the eastern Eurasian Basin of the Arctic Ocean and evaluating its drivers and consequences
Dolly More
International Arctic Research Center and College of Natural Science and Mathematics, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
International Arctic Research Center and College of Natural Science and Mathematics, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
Andrey V. Pnyushkov
International Arctic Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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Masao Uchida, Yuichiro Kumamoto, Igor Polyakov, Kanako Mantoku, Chie Amano, Motoo Utsumi, Yongwon Kim, Motoyo Itoh, Shigeto Nishino, Koji Shimada, and Naomi Harada
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-493, https://doi.org/10.5194/essd-2026-493, 2026
Preprint under review for ESSD
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We present a new full-water-column Arctic Ocean dataset of dissolved inorganic carbon (DIC) radiocarbon (Δ¹⁴C) and δ¹³C, from R/V Mirai cruises (1999–2009) and the 2008 NABOS expedition: 255 new DIC Δ¹⁴C measurements (42 from NABOS 2008), each paired with δ¹³C and concentration. Combined with published records spanning 1979–2021, it resolves the surface, halocline, Atlantic Water and deep layers. The Atlantification interpretation appears in a companion paper.
Igor V. Polyakov, Andrey V. Pnyushkov, Eddy C. Carmack, Matthew Charette, Kyoung-Ho Cho, Steven Dykstra, Jari Haapala, Jinyoung Jung, Lauren Kipp, Eun Jin Yang, and Sergey Molodtsov
Ocean Sci., 21, 3105–3122, https://doi.org/10.5194/os-21-3105-2025, https://doi.org/10.5194/os-21-3105-2025, 2025
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The Siberian Arctic Ocean greatly influences the Arctic climate system. Moreover, the region is experiencing some of the most notable Arctic climate change. In the summer, strong near-inertial currents in the upper (<30m) ocean account for more than half of the current speed and shear. In the winter, upper ocean ventilation due to atlantification distributes wind energy to far deeper (>100m) layers. Understanding the implications for mixing and halocline weakening depends on these findings.
Naoya Kanna, Kazutaka Tateyama, Takuji Waseda, Anna Timofeeva, Maria Papadimitraki, Laura Whitmore, Hajime Obata, Daiki Nomura, Hiroshi Ogawa, Youhei Yamashita, and Igor Polyakov
Biogeosciences, 22, 1057–1076, https://doi.org/10.5194/bg-22-1057-2025, https://doi.org/10.5194/bg-22-1057-2025, 2025
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This article presents data on iron and manganese, essential micronutrients for primary producers in the Arctic Laptev and East Siberian seas (LESS). There, observations were made through international cooperation with the Nansen and Amundsen Basin Observational System expedition during the late summer of 2021. The results from this study indicate that the major sources controlling the iron and manganese distributions on the LESS continental margins are river discharge and shelf sediment input.
Qiang Wang, Qi Shu, Alexandra Bozec, Eric P. Chassignet, Pier Giuseppe Fogli, Baylor Fox-Kemper, Andy McC. Hogg, Doroteaciro Iovino, Andrew E. Kiss, Nikolay Koldunov, Julien Le Sommer, Yiwen Li, Pengfei Lin, Hailong Liu, Igor Polyakov, Patrick Scholz, Dmitry Sidorenko, Shizhu Wang, and Xiaobiao Xu
Geosci. Model Dev., 17, 347–379, https://doi.org/10.5194/gmd-17-347-2024, https://doi.org/10.5194/gmd-17-347-2024, 2024
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Increasing resolution improves model skills in simulating the Arctic Ocean, but other factors such as parameterizations and numerics are at least of the same importance for obtaining reliable simulations.
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Short summary
The Arctic Ocean is changing fast, and river runoff plays a key role. Between 2015 and 2017, unusually large flows from Siberia’s Yenisey and Ob Rivers made the eastern Arctic much fresher. This stabilized the ocean, slowed currents, and reduced heat from below, allowing thicker sea ice to persist through summer. The study shows how bursts of river discharge can reshape the Arctic and help sea ice survive.
The Arctic Ocean is changing fast, and river runoff plays a key role. Between 2015 and 2017,...