Articles | Volume 21, issue 4
https://doi.org/10.5194/os-21-1291-2025
© Author(s) 2025. 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-21-1291-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Topographic modulation on the layered circulation in the South China Sea
Qibang Tang
Department of Ocean Science and Technology, State Key Laboratory of Internet of Things for Smart City, University of Macau, Macau, China
Centre of Ocean Research in Hong Kong and Macau (CORE), Hong Kong, China
Department of Ocean Science and Technology, State Key Laboratory of Internet of Things for Smart City, University of Macau, Macau, China
Centre of Ocean Research in Hong Kong and Macau (CORE), Hong Kong, China
Zhiqiang Liu
Department of Ocean Science and Engineering and Center for Complex Flows and Soft Matter Research, Southern University of Science and Technology, Shenzhen, China
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Yunping Song, Yunxin Lin, Peng Zhan, Zhiqiang Liu, and Zhongya Cai
EGUsphere, https://doi.org/10.5194/egusphere-2025-2712, https://doi.org/10.5194/egusphere-2025-2712, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
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Our research investigates year-to-year changes in the Northern South China Sea's shelf currents, which are influenced by climate patterns like El Niño and freshwater discharge from the Pearl River Estuary. Using long-term observations and computer models , we analyzed these dynamic shifts. Our findings reveal that El Niño generates distinct sea-level patterns, intensifying currents and altering large-scale ocean flows, while increased river runoff reduces coastal salinity.
Mingyu Li, Alessandro Stocchino, Zhongya Cai, and Tingting Zu
Ocean Sci., 20, 931–944, https://doi.org/10.5194/os-20-931-2024, https://doi.org/10.5194/os-20-931-2024, 2024
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In this study, we explored how water accumulates in a coastal estuary, a key factor affecting the estuary's environmental health and ecosystem. We revealed significant bottom accumulations influenced by plume fronts and velocity convergence, with notable seasonal variability. By analyzing trajectories, we identified subregions with distinct accumulation patterns and examined their interconnections, highlighting the substantial impact of tides and river discharge on these dynamics.
Fanglou Liao, Xiao Hua Wang, and Zhiqiang Liu
Geosci. Model Dev., 15, 1129–1153, https://doi.org/10.5194/gmd-15-1129-2022, https://doi.org/10.5194/gmd-15-1129-2022, 2022
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The ocean heat content (OHC) estimated using two eddying hindcast simulations, OFES1 and OFES2, was compared from 1960 to 2016, with observation-based results as a reference. Marked differences were found, especially in the Atlantic Ocean. These were related to the differences in the net surface heating, heat advection, and vertical heat diffusion. These documented differences may help the community better understand and use these quasi-global high-resolution datasets for their own purposes.
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Ciara Pimm, Andrew J. S. Meijers, Dani C. Jones, and Richard G. Williams
Ocean Sci., 21, 1237–1253, https://doi.org/10.5194/os-21-1237-2025, https://doi.org/10.5194/os-21-1237-2025, 2025
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Ocean Sci., 21, 1081–1103, https://doi.org/10.5194/os-21-1081-2025, https://doi.org/10.5194/os-21-1081-2025, 2025
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The ocean buffers human-induced climate change by taking up excess heat from the atmosphere. In this study, we use an ensemble of global climate models to study the physical processes which set the efficiency at which this heat is stored in the ocean. We reconcile previous attempts to explain controls on this efficiency and find that Southern Ocean stratification is a key model property due to its influence on the local overturning circulation and its connection to the subpolar North Atlantic.
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The North Atlantic Subpolar Gyre (SPG) forms dense water as part of the Atlantic Meridional Overturning Circulation. To explore the factors controlling dense water formation around the SPG, we trace the pathways of virtual water parcels in a high-resolution ocean model. We show that the amount of dense water formed around the SPG depends principally on the availability of light waters flowing northward, such that a stronger SPG circulation results in more dense water formation along-stream.
Hendrik Großelindemann, Frederic S. Castruccio, Gokhan Danabasoglu, and Arne Biastoch
Ocean Sci., 21, 93–112, https://doi.org/10.5194/os-21-93-2025, https://doi.org/10.5194/os-21-93-2025, 2025
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This study investigates the Agulhas Leakage and examines its role in the global ocean circulation. It utilises a high-resolution Earth system model and a preindustrial climate to look at the response of the Agulhas Leakage to the wind field and the Atlantic Meridional Overturning Circulation (AMOC) and its evolution under climate change. The Agulhas Leakage could influence the stability of the AMOC, whose possible collapse would impact the climate in the Northern Hemisphere.
Olivier Narinc, Thierry Penduff, Guillaume Maze, Stéphanie Leroux, and Jean-Marc Molines
Ocean Sci., 20, 1351–1365, https://doi.org/10.5194/os-20-1351-2024, https://doi.org/10.5194/os-20-1351-2024, 2024
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Eike E. Köhn, Richard J. Greatbatch, Peter Brandt, and Martin Claus
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The latitudinally alternating zonal jets are a ubiquitous feature of the ocean. We use a simple model to illustrate the potential role of these jets in the formation, maintenance, and multidecadal variability in the oxygen minimum zones, using the eastern tropical North Atlantic oxygen minimum zone as an example.
René M. van Westen and Henk A. Dijkstra
Ocean Sci., 20, 549–567, https://doi.org/10.5194/os-20-549-2024, https://doi.org/10.5194/os-20-549-2024, 2024
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The Atlantic Meridional Overturning Circulation (AMOC) is an important component in the global climate system. Observations of the present-day AMOC indicate that it may weaken or collapse under global warming, with profound disruptive effects on future climate. However, AMOC weakening is not correctly represented because an important feedback is underestimated due to biases in the Atlantic's freshwater budget. Here we address these biases in several state-of-the-art climate model simulations.
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Ocean Sci., 20, 521–547, https://doi.org/10.5194/os-20-521-2024, https://doi.org/10.5194/os-20-521-2024, 2024
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We examine factors affecting variability in the volume of Labrador Sea Water (LSW), a water mass that is important for the uptake and storage of heat and carbon in the Atlantic Ocean. We find that LSW accumulated in the Labrador Sea exhibits a lagged response to remote conditions: surface wind stress, heat flux, and freshwater flux anomalies, especially along the pathways of the North Atlantic Current branches. We use our results to reconstruct and attribute historical changes in LSW volume.
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Short summary
The South China Sea is the largest semi-enclosed marginal sea in the western Pacific, featuring unique layered circulation with rotating currents in its upper, middle, and deep layers. This study uses simulations to explore how stronger currents in the upper layer influence circulation across the entire basin. The vorticity analyses show that the enhanced upper currents increase the strength of middle and deep currents, driven by changes in bottom pressure and cross-slope movements.
The South China Sea is the largest semi-enclosed marginal sea in the western Pacific, featuring...