Articles | Volume 22, issue 1
https://doi.org/10.5194/os-22-565-2026
© 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-22-565-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Feb 2026
Research article |
| 12 Feb 2026
| 12 Feb 2026
The Arctic overturning circulation: transformations, pathways and timescales
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Carlo Mans
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Marius Årthun
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Kristofer Döös
Department of Meteorology, Stockholm University, Stockholm, Sweden
Dafydd Gwyn Evans
National Oceanography Centre, Southampton, UK
Yanchun He
Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research, Bergen, Norway
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Jakob Simon Dörr, David B. Bonan, Marius Årthun, Lea Svendsen, and Robert C. J. Wills
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Oliver John Tooth, Helen Louise Johnson, Chris Wilson, and Dafydd Gwyn Evans
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Dafydd Gwyn Evans, N. Penny Holliday, Sheldon Bacon, and Isabela Le Bras
Ocean Sci., 19, 745–768, https://doi.org/10.5194/os-19-745-2023, https://doi.org/10.5194/os-19-745-2023, 2023
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This study investigates the processes that form dense water in the high latitudes of the North Atlantic to determine how they affect the overturning circulation in the Atlantic. We show for the first time that turbulent mixing is an important driver in the formation of dense water, along with the loss of heat from the ocean to the atmosphere. We point out that the simulation of turbulent mixing in ocean–climate models must improve to better predict the ocean's response to climate change.
Ole Rieke, Marius Årthun, and Jakob Simon Dörr
The Cryosphere, 17, 1445–1456, https://doi.org/10.5194/tc-17-1445-2023, https://doi.org/10.5194/tc-17-1445-2023, 2023
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The Barents Sea is the region of most intense winter sea ice loss, and future projections show a continued decline towards ice-free conditions by the end of this century but with large fluctuations. Here we use climate model simulations to look at the occurrence and drivers of rapid ice change events in the Barents Sea that are much stronger than the average ice loss. A better understanding of these events will contribute to improved sea ice predictions in the Barents Sea.
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One of the most striking and robust features of climate change is the acceleration of the atmospheric water cycle branch. Earlier studies were able to provide a quantification of the global atmospheric water cycle, but they missed addressing the atmospheric water transport connectivity within and between ocean basins and land. These shortcomings were overcome in the present study and presented a complete synthesised and quantitative view of the atmospheric water cycle.
Marilena Oltmanns, N. Penny Holliday, James Screen, D. Gwyn Evans, Simon A. Josey, Sheldon Bacon, and Ben I. Moat
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Revised manuscript not accepted
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The Arctic is currently warming twice as fast as the global average. This results in enhanced melting and thus freshwater releases into the North Atlantic. Using a combination of observations and models, we show that atmosphere-ocean feedbacks initiated by freshwater releases into the North Atlantic lead to warmer and drier weather over Europe in subsequent summers. The existence of this dynamical link suggests that European summer weather can potentially be predicted months to years in advance.
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Short summary
The Arctic Ocean plays a key role in the global ocean circulation by producing dense waters that feed the lower limb of the Atlantic meridional overturning circulation (AMOC). We use a high-resolution ocean simulation to investigate the pathways and mechanisms through which these dense waters are formed in the Arctic. Our results show that surface cooling in the Barents Sea dominates the dense water production, but that internal mixing plays a role at high densities.
The Arctic Ocean plays a key role in the global ocean circulation by producing dense waters that...
