High-resolution simulation of upper-ocean submesoscale variability in the South China Sea:Spatial and seasonal dynamical regimes  

作　　者：Haijin Cao Xin Meng Zhiyou Jing Xiaoxiao Yang 

机构地区：[1]Key Laboratory of Marine Hazards Forecasting of Ministry of Natural Resources,Hohai University,Nanjing,210024,China [2]College of Oceanography,Hohai University,Nanjing,210024,China [3]State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou,510301,China

出　　处：《Acta Oceanologica Sinica》2022年第7期26-41,共16页海洋学报（英文版）

基　　金：The National Key Research and Development Program of China under contract No.2017YFA0604104;the National Natural Science Foundation of China under contract Nos 42176004,92058201 and 41776040;the Fundamental Research Funds for the Central Universities under contract No.B220202050.

摘　　要：Submesoscale processes in marginal seas usually have complex generating mechanisms,highly dependent on the local background flow and forcing.This numerical study investigates the spatial and seasonal differences of submesoscale activities in the upper ocean of the South China Sea(SCS)and the different dynamical regimes for sub-regions.The spatial and seasonal variations of vertical vorticity,horizontal convergence,lateral buoyancy gradient,and strain rate are analyzed to compare the submesoscale phenomenon within four sub-regions,the northern region near the Luzon Strait(R1),the middle ocean basin(R2),the western SCS(R3),and the southern SCS(R4).The results suggest that the SCS submesoscale processes are highly heterogeneous in space,with different seasonalities in each sub-region.The submesoscale activities in the northern sub-regions(R1,R2)are active in winter but weak in summer,while there appears an almost seasonal anti-phase in the western region(R3)compared to R1 and R2.Interestingly,no clear seasonality of submesoscale features is shown in the southern region(R4).Further analysis of Ertel potential vorticity reveals different generating mechanisms of submesoscale processes in different sub-regions.Correlation analyses also show the vertical extent of vertical velocity and the role of monsoon in generating submesoscale activities in the upper ocean of sub-regions.All these results suggest that the sub-regions have different regimes for submesoscale processes,e.g.,Kuroshio intrusion(R1),monsoon modulation(R2),frontal effects(R3),topography wakes(R4).

关 键 词：SUBMESOSCALE South China Sea high-resolution simulation spatial difference seasonal difference 

分 类 号：P73[天文地球—海洋科学]