OS - recent papers

TS-Cast: deep learning for subsurface ocean reconstruction from satellite observations in the northwestern Pacific

Thu, 16 Jul 2026 08:21:33 +0200

TS-Cast: deep learning for subsurface ocean reconstruction from satellite observations in the northwestern Pacific
Jeong-Yeob Chae, Kathleen A. Donohue, and Jae-Hun Park
Ocean Sci., 22, 2161–2177, https://doi.org/10.5194/os-22-2161-2026, 2026
We introduce TS (Temperature-Salinity)-Cast, a novel deep neural network that reconstructs subsurface thermohaline structures from satellite observations. Validated against independent time-series data, TS-Cast achieves root mean squared errors of < 1 °C and < 0.1 psu in the upper 500 m of the Kuroshio Extension, comparable or surpassing data-assimilated numerical models. Critically, we demonstrate that the physical limitations of the input satellite data fundamentally constrain the model's predictive skill.

Filamentogenesis and Filamentolysis of a Low-Density Filament: Dynamic Processes in the Near-Surface Ocean Under Tidal Forcing

Thu, 09 Jul 2026 08:21:33 +0200

Filamentogenesis and Filamentolysis of a Low-Density Filament: Dynamic Processes in the Near-Surface Ocean Under Tidal Forcing
Michelle Albinus, Thomas H. Badewien, Lisa Gassen, Oliver Wurl, and Jens Meyerjürgens
Ocean Sci., 22, 2143–2160, https://doi.org/10.5194/os-22-2143-2026, 2026
This study reveals the structure and alteration of a narrow freshwater-driven ocean low-density filament and its evolution through tidal modulationa an dlocale filament kinematics. Using multi-platform in situ observations, it is shown that these submesoscale features can rapidly being altered and reshape in near-surface waters, influencing how energy and heat alter just below the ocean-atmosphere interface.

Wave-induced sediment resuspension potential in the Finnish Archipelago, Baltic Sea: integrating field measurements with large-scale numerical model simulations

Mon, 06 Jul 2026 08:21:33 +0200

Wave-induced sediment resuspension potential in the Finnish Archipelago, Baltic Sea: integrating field measurements with large-scale numerical model simulations
Jan-Victor Björkqvist, Mari Savela, Heidi Pettersson, Victor Alari, and Alf Norkko
Ocean Sci., 22, 2123–2141, https://doi.org/10.5194/os-22-2123-2026, 2026
Strong motions caused by surface waves can set the material at the bottom in motion. How strong the wave motions need to be depends on the bottom type, for example mud or sand. We estimated how often waves can lift particles from the bottom by comparing wave model results to sea floor samples in the laboratory. We included the effect of seasonal biological activity, which was found to be significant.

A T-DINEOF model for multiple oceanic variables reconstruction

Fri, 03 Jul 2026 08:21:33 +0200

A T-DINEOF model for multiple oceanic variables reconstruction
Bo Ping, Ruiting Yang, Yunshan Meng, Fenzhen Su, and Cunjin Xue
Ocean Sci., 22, 2101–2122, https://doi.org/10.5194/os-22-2101-2026, 2026
Satellite observations are often incomplete due to cloud cover, resulting in missing ocean data. To address this, we developed T-DINEOF (Data Interpolating Empirical Orthogonal Function), a reconstruction method that simultaneously estimates sea surface temperature, chlorophyll concentration, and wind conditions by learning relationships among variables. Results show that T-DINEOF improves reconstruction accuracy, especially in regions with sparse data or weak correlations, providing more reliable ocean information for environmental monitoring.

A multidecadal sea level rise and its hiatus in the tropical Atlantic margin off northwest Africa

Wed, 01 Jul 2026 08:21:33 +0200

A multidecadal sea level rise and its hiatus in the tropical Atlantic margin off northwest Africa
Hamed D. Ibrahim and Yunfang Sun
Ocean Sci., 22, 2059–2081, https://doi.org/10.5194/os-22-2059-2026, 2026
This study characterizes a multidecadal sea level rise and its pause in the tropical North Atlantic margin off northwest Africa hosting important marine fisheries. The pause in sea level rise is owing to temperature-driven seawater contraction that counteracted salt-driven expansion and mass accumulation. Currents originating elsewhere freshened the margin with low-salinity water, highlighting a multidecadal linkage between salinity and sea level anomalies in different North Atlantic regions.

A Digital Twin Ocean: can we improve coastal ocean forecasts using targeted marine autonomy?

Wed, 01 Jul 2026 08:21:33 +0200

A Digital Twin Ocean: can we improve coastal ocean forecasts using targeted marine autonomy?
Dale Partridge, Deep Banerjee, David Ford, Ke Wang, Jozef Skákala, Juliane Wihsgott, Prathyush P. Menon, Susan Kay, Daniel Clewley, Andrea Rochner, Emma Sullivan, and Matthew Palmer
Ocean Sci., 22, 2083–2100, https://doi.org/10.5194/os-22-2083-2026, 2026
This study outlines the development and testing of a Digital Twin Ocean (DTO) framework, aimed at improving coastal ocean forecasts through the use of autonomous underwater gliders. A fleet of gliders were deployed in the western English Channel during August–September 2024 to collect measurements of temperature, salinity, chlorophyll and oxygen, aiming to track the movement of the harmful algal bloom Karenia mikimotoi.

The past evolution of marine heatwaves and their drivers in the southern North Sea

Tue, 30 Jun 2026 08:21:33 +0200

The past evolution of marine heatwaves and their drivers in the southern North Sea
Tobias Schulzki, Franziska U. Schwarzkopf, and Arne Biastoch
Ocean Sci., 22, 2027–2058, https://doi.org/10.5194/os-22-2027-2026, 2026
Marine heatwaves are periods of unusually warm ocean temperatures that can affect ecosystems and weather. In the North Sea, they have become more frequent over recent decades, but their peak intensity has decreased in many areas. Our results show that marine heatwaves depend on both short-term weather and longer seasonal to decadal variability. The local atmospheric conditions play a key role in the German Bight.

Dynamically downscaled future projections of the Northwest Atlantic Ocean across low to high emissions scenarios

Fri, 26 Jun 2026 08:21:33 +0200

Dynamically downscaled future projections of the Northwest Atlantic Ocean across low to high emissions scenarios
Dongmin Kim, Andrew C. Ross, Sang-Ik Shin, Fabian A. Gomez, Jasmin G. John, Denis L. Volkov, Sang-Ki Lee, Michael A. Alexander, and Charles A. Stock
Ocean Sci., 22, 1987–2009, https://doi.org/10.5194/os-22-1987-2026, 2026
Using high-resolution Modular Ocean Model version 6, we projected Northwest Atlantic changes under four future emission scenarios. Results show a weakening Gulf Stream reduces upwelling, causing significant shelf warming and salinification. This also leads to dynamic sea-level rise along the US East Coast, particularly in the South Atlantic Bight, with critical implications for marine ecosystems and coastal risks.

Modulation of internal tides properties off the Vitória–Trindade ridge during contrasted seasons from altimetry and a regional ocean model

Fri, 26 Jun 2026 08:21:33 +0200

Modulation of internal tides properties off the Vitória–Trindade ridge during contrasted seasons from altimetry and a regional ocean model
Perrine Bauchot, Ariane Koch-Larrouy, Michel Tchilibou, Loren Carrère, Fabrice Hernandez, Guillaume Morvan, and Jérôme Chanut
Ocean Sci., 22, 2011–2025, https://doi.org/10.5194/os-22-2011-2026, 2026
The Vitória–Trindade Ridge off the Brazilian coast is a hotspot for internal tides, which drive energy and nutrients exchanges in the ocean. Using satellite data and a high-resolution ocean model, we study what influences these small waves in this region. We show that internal tides are generated more strongly in summer and lose energy faster in winter. Ocean eddies may also affect their fate. These results are essential for understanding oceanic energy pathways and refine model predictions.

Investigating the predictability of marine heatwaves at subseasonal to seasonal timescales in New Caledonia, South Pacific

Tue, 23 Jun 2026 08:21:33 +0200

Investigating the predictability of marine heatwaves at subseasonal to seasonal timescales in New Caledonia, South Pacific
Inès Mangolte, Sophie Cravatte, Alexandre Ganachaud, and Christophe Menkes
Ocean Sci., 22, 1937–1964, https://doi.org/10.5194/os-22-1937-2026, 2026
Marine heatwaves pose a serious threat to marine ecosystems that will become increasingly important with climate change. Here we show in the Southwest Pacific that dynamical forecasting systems are able to forecast long, large-scale marine heatwaves occurring in austral winter, but have less skill in predicting smaller, shorter events, and summer events. We discuss the implications for operational forecasts dedicated to help marine managers to prepare and mitigate some of their impacts.

Interaction of AMOC and intrinsic multidecadal Southern Ocean variability

Tue, 23 Jun 2026 08:21:33 +0200

Interaction of AMOC and intrinsic multidecadal Southern Ocean variability
Emma J. V. Smolders, René M. van Westen, and Henk A. Dijkstra
Ocean Sci., 22, 1965–1985, https://doi.org/10.5194/os-22-1965-2026, 2026
The Southern Ocean shows strong natural variability on multi-decadal time scales, known as the Southern Ocean Mode (SOM). Using high-resolution ocean simulations, we show that a collapse of the Atlantic Meridional Overturning Circulation (AMOC) strongly weakens the SOM. This weakening is linked to changes in ocean density, a slowdown of the Antarctic Circumpolar Current, and shifts in deep convection across the Southern Ocean.

Estuarine mixing

Mon, 22 Jun 2026 08:21:33 +0200

Estuarine mixing
Hans Burchard, Knut Klingbeil, Xiangyu Li, Lloyd Reese, and W. Rockwell Geyer
Ocean Sci., 22, 1875–1918, https://doi.org/10.5194/os-22-1875-2026, 2026
This review presents major aspects of estuarine mixing. Due to the large amounts of brackish water in estuaries produced by mixing of fresh river discharge and salty ocean water, mixing is one major characteristic of what is an estuary. Mixing is quantified locally as well as on estuary-wide scales. Diagnostics of integrated mixing are given for estuarine volumes bounded by transects as well as surfaces of constant salinity moving with the flow. Examples for real-world estuaries are given.

Stratified-turbulence observations dominated by slantwise downward convective warm-water periods in the deep Mediterranean

Mon, 22 Jun 2026 08:21:33 +0200

Stratified-turbulence observations dominated by slantwise downward convective warm-water periods in the deep Mediterranean
Hans van Haren
Ocean Sci., 22, 1919–1936, https://doi.org/10.5194/os-22-1919-2026, 2026
Turbulence is vital for life, also in 2500-m deep Mediterranean waters. Yearlong observations with about 3000 high-resolution temperature sensors show: About half the time, relatively warm stratified waters are moved from 100’s of meters higher levels to near the seafloor. These internal-wave and eddy-induced motions are three times more turbulent than those induced via general geothermal heating from below, and about ten times more turbulent than those from open-ocean processes.

Along-channel variability of Total Exchange Flow in a narrow, well-mixed estuary: influence of the M4 tide

Thu, 18 Jun 2026 08:21:33 +0200

Along-channel variability of Total Exchange Flow in a narrow, well-mixed estuary: influence of the M4 tide
Manuel Díez-Minguito and Hans Burchard
Ocean Sci., 22, 1861–1874, https://doi.org/10.5194/os-22-1861-2026, 2026
Combining field observations with an analytical tidal scenario, we estimated in the Guadalquivir estuary its Total Exchange Flow (TEF), which has implications for water quality and residence times. The influence of tidal asymmetry on TEF is also explored. Results reveal a spatial variability in TEF and that salinity–current covariance exerts greater control on TEF than tidal asymmetry. The approach is suitable for regional studies evaluating sensitivity to changes in runoff, salinity and tides.

Radionuclides as tracers of Arctic outflows: pathways, water mass mixing, and freshwater input to Davis Strait and the Labrador Sea

Wed, 17 Jun 2026 08:21:33 +0200

Radionuclides as tracers of Arctic outflows: pathways, water mass mixing, and freshwater input to Davis Strait and the Labrador Sea
Lisa G. T. Leist, Maxi Castrillejo, Kumiko Azetsu-Scott, Craig Lee, Jed Lenetsky, Marc Ringuette, Christof Vockenhuber, Habacuc Pérez-Tribouillier, Catherine Jeandel, Jean-Éric Tremblay, and Núria Casacuberta
Ocean Sci., 22, 1835–1860, https://doi.org/10.5194/os-22-1835-2026, 2026
The Arctic and Atlantic Oceans are connected by narrow passages, and the exchange of waters affect global climate. Using artificial radionuclides from nuclear reprocessing discharges, we traced the origin of water masses from the Arctic to the Labrador Sea. Results show that waters from Canadian Arctic origin entering via Lancaster Sound are a key freshwater source to the Labrador Sea. These flows strongly influence the formation of deep waters in the Atlantic, vital for the global circulation.

Greenland tip jet and deep convection in the Irminger Sea: disentangling the roles of heat loss and wind stress

Fri, 12 Jun 2026 08:21:33 +0200

Greenland tip jet and deep convection in the Irminger Sea: disentangling the roles of heat loss and wind stress
Aleksandr M. Fedorov, M. Femke De Jong, Claudia E. Wieners, Elodie Duyck, and Henk A. Dijkstra
Ocean Sci., 22, 1819–1834, https://doi.org/10.5194/os-22-1819-2026, 2026
Deep ocean mixing in the North Atlantic helps power major currents, but it is weakening as the surface warms. We used a high-resolution ocean model and separate experiments that added either extra heat loss, extra wind, or both during Greenland storm events. Extra heat loss caused most of the deep mixing, but strong winds also helped by mixing salty water upward and removing the fresh surface layer early in winter. This wind effect may modulate the future decline of deep mixing.

Gliding through marine heatwaves: subsurface biogeochemical characteristics on the Australian continental shelf

Thu, 11 Jun 2026 08:21:33 +0200

Gliding through marine heatwaves: subsurface biogeochemical characteristics on the Australian continental shelf
Daneeja Mawren, Julia Araujo, Romain Le Gendre, Jessica A. Benthuysen, Franck Eitel Kemgang Ghomsi, Jayanthi S. Saranya, and Amandine Schaeffer
Ocean Sci., 22, 1793–1817, https://doi.org/10.5194/os-22-1793-2026, 2026
Using 16 years of ocean glider data, we show that marine heatwaves are characterised by shallow mixed layers and alter subsurface biogeochemistry across Australia’s continental shelf. Surface chlorophyll generally declined, but strong stratification and event severity promoted deeper, intensified chlorophyll maxima, highlighting region-specific ecological responses to heatwaves.

Sea ice melt drives vertical pCO2 variability modulating air–sea gas exchange

Wed, 03 Jun 2026 08:21:33 +0200

Sea ice melt drives vertical pCO2 variability modulating air–sea gas exchange
Henry C. Henson, Dorte H. Søgaard, Bjarne Jensen, Kunuk Lennert, Tim Papakyriakou, Mikael K. Sejr, Jakob Sievers, Søren Rysgaard, and Lise Lotte Sørensen
Ocean Sci., 22, 1781–1792, https://doi.org/10.5194/os-22-1781-2026, 2026
Sea ice melt adds less-saline water to the surface ocean. This creates vertical gradients in salinity, temperature, and partial pressures of carbon dioxide (pCO2). The concentration difference of pCO2 across the air-ocean boundary is used to estimate gas transfer. Thus, the depth that we measure will impact our estimates. Similar patterns were observed in multiple Arctic fjords years apart, suggesting these vertical gradients may be common during the spring melt season.

On the fate of the Irminger Current water and its impact on the convection region in the Irminger Sea – a Lagrangian model study

Wed, 03 Jun 2026 08:21:33 +0200

On the fate of the Irminger Current water and its impact on the convection region in the Irminger Sea – a Lagrangian model study
Nora Fried, Renske Gelderloos, Oliver J. Tooth, Caroline A. Katsman, and M. Femke de Jong
Ocean Sci., 22, 1763–1780, https://doi.org/10.5194/os-22-1763-2026, 2026
This study investigates how much warm and saline subtropical-origin water flowing in the Irminger Current (IC) can enter the Irminger Sea convection region by releasing virtual particles in an ocean model. We show that one quarter of IC waters enter the convection region with the potential to increase local stratification. Our results suggest that changes in the water mass properties of the IC have the potential to influence the strength of deep convection in the Irminger Sea.

Intraseasonal modulation of sea surface temperatures in the Tropical North Atlantic by African Easterly Waves

Tue, 02 Jun 2026 08:21:33 +0200

Intraseasonal modulation of sea surface temperatures in the Tropical North Atlantic by African Easterly Waves
Marc Kakante Mendy, Florent Gasparin, Manon Gévaudan, Moussa Diakhaté, Issa Sakho, and Julien Jouanno
Ocean Sci., 22, 1745–1762, https://doi.org/10.5194/os-22-1745-2026, 2026
The North Tropical Atlantic plays an important role in shaping climate in the region. In our study we examined how African Easterly Waves influence the ocean surface. Using numerical modelling and buoy records, we found that these waves can warm or cool the sea by more than half a degree. The faster waves have the strongest impact. Because sea temperature affects rainfall and storms, understanding these waves can help improve weather and climate forecasts.