The influence of cold filaments on the evolution of dipole structures

Frontiers in Marine Science

Marine Science

Guoping Gao¹  Qi Yang²  Guihua Wang³  Ruili Sun⁴  Chi Xu⁵ 

[1] College of Marine Science, Shanghai Ocean University, Shanghai, China;College of Marine Science, Shanghai Ocean University, Shanghai, China;Shanghai Meteorological Bureau, China Meteorological Administration, Shanghai, China;Department of Atmospheric and Oceanic Sciences and CMA-FDU (China Meteorological Administration and Fudan University) Joint Laboratory of Marine Meteorology, Fudan University, Shanghai, China;Hainan Institute of Zhejiang University, Sanya, Hainan, China;Key Laboratory of Science and Technology on Operational Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China;State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China;

关键词: filament;    mesoscale eddy dipole;    interaction;    structure;    Lagrangian trajectory;    chlorophyll;   

DOI  :  10.3389/fmars.2023.1113993

 received in 2022-12-02, accepted in 2023-05-29,  发布年份 2023

来源: Frontiers

【 摘 要 】

Mesoscale eddy dipoles are oceanographic structures that can transport ocean water parcels horizontally and vertically in ways that differ from individual mesoscale eddies. The most conspicuous additional feature that presents in dipoles is the cold filament (CF) that can be spontaneously generated between a dipole’s anticyclonic eddy (AE) and cyclonic eddy (CE). A case study in this paper shows that the interaction between the CF and the CE component of the dipole is associated with the structural evolution of the dipole. This interaction is verified in synthesis and normalization studies of the CF dipoles. The CF-dipole interaction entrains CF water into the center of the dipole’ CE and leads to a cold and high chlorophyll center in the upper layer of the CE. The formation of this cold center changes the dipole’s structure by eliminating the phase difference between the thermal and dynamic centers of the dipole. The entrainment also provides a new mechanism for the development of high chlorophyll levels in the CE. In the analysis of the HYCOM (Hybrid Coordinate Ocean Model) simulation of a synthetic CF dipole, the AE has a three-zone structure while the CE only has two. The convergence of the CE’s outermost zone results in a biased interaction.

【 授权许可】

Unknown   
Copyright © 2023 Yang, Wang, Xu, Gao and Sun