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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                                    This preprint is open for discussion and under review for Ocean Science (OS). 
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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...
            
         
 
                        
                                         
                        
                                         
             
             
            