Cite this paper:
SONG Xinxin, YUAN Dongliang, LI Ruixiang, WANG Zheng. Migration of mesoscale eddies across a leaping or penetrating western boundary current in the vicinity of a gap[J]. HaiyangYuHuZhao, 2018, 36(6): 2098-2109

Migration of mesoscale eddies across a leaping or penetrating western boundary current in the vicinity of a gap

SONG Xinxin1,2,3, YUAN Dongliang1,3, LI Ruixiang4, WANG Zheng1
1 Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, and Function Laboratory for Ocean Dynamics and Climate, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China;
2 Key Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, and Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China;
3 University of Chinese Academy of Sciences, Beijing 100049, China;
4 South China Sea Marine Survey and Technology Center, State Oceanic Administration, Guangzhou 510300, China
Abstract:
A 1.5-layer quasi-geostrophic reduced gravity ocean circulation model is used to study the propagation of mesoscale eddies across a western boundary current (WBC) either leaping across or penetrating in an anti-cyclonic path through the gap. The steady leaping WBC nearly blocks all eddies from propagating across it through the gap completely. However, both cyclonic and anti-cyclonic eddies can migrate across a penetrating WBC in the vicinity of a gap, while inducing an opposite type of eddies on the cyclonic side of the WBC by weakening or strengthening the intrusion of the WBC. Both type of eddies gained strength from the WBC in the course of the propagation across the WBC in the gap. Eddies approaching the gap from the upstream are found to migrate more easily into the western basin due to the advection of the WBC. The migration speeds of the eddies are almost unchanged by the presence of the WBC in all experiments.
Key words:    mesoscale eddy|Western Boundary Current|gap   
Received: 2017-10-25   Revised:
Tools
PDF (1354 KB) Free
Print this page
Add to favorites
Email this article to others
Authors
Articles by SONG Xinxin
Articles by YUAN Dongliang
Articles by LI Ruixiang
Articles by WANG Zheng
References:
Chelton D B, Schlax M G, Samelson R M. 2011. Global observations of nonlinear mesoscale eddies. Progress in Oceanography, 91(2):167-216.
Chern C S, Wang J. 2005. Interactions of mesoscale eddy and western boundary current:a reduced-gravity numerical model study. Journal of Oceanography, 61(2):271-282.
Johnson E R, McDonald N R. 2005. Vortices near barriers with multiple gaps. Journal of Fluid Mechanics, 531:335-358.
Kuehl J J, Sheremet V A. 2014. Two-layer gap-leaping oceanic boundary currents:experimental investigation. Journal of Fluid Mechanics, 740:97-113.
Li L, Nowlin Jr W D, Su J. 1998. Anticyclonic rings from the Kuroshio in the South China Sea. Deep Sea Research Part I:Oceanographic Research Papers 45(9):1 469-1 482.
Li R X. 2008. Dynamics of eddy-induced Kuroshio variability in the Luzon Strait. University of Chinese Academy of Sciences, Beijing, China. p.1-44. (in Chinese with English abstract)
Lu J Y, Liu Q Y. 2013. Gap-leaping Kuroshio and blocking westward-propagating Rossby wave and eddy in the Luzon Strait. Journal of Geophysical Research:Oceans, 118(3):1 170-1 181.
McWilliams J C, Flierl G R. 1979. On the evolution of isolated, nonlinear vortices. Journal of Physical Oceanography, 9:1 155-1 182.
McWilliams J C. 2006. Fundamentals of Geophysical Fluid Dynamics. Cambridge University Press, Cambridge. 283p.
Nitani H. 1972. Beginning of the kuroshio. In:Stommel H, Yoshida K eds. Kuroshio:Its Physical Aspects. University of Tokyo Press, Tokyo. p.129-163.
Nof D. 1988. Eddy-wall interactions. Journal of Marine Research, 46(3):527-555.
Pedlosky J. 1994. Ridges and recirculations:gaps and jets.Journal of Physical Oceanography, 24(2):2 703.
Pu S Z, Yu H L, Jiang S N. 1992. Branchings of Kuroshio into Bashi Channel and the South China Sea. Tropic Oceanology, 11(2):1-8. (in Chinese with English abstract)
Sheremet V A. 2001. Hysteresis of a western boundary current leaping across a gap. Journal of Physical Oceanography, 31(5):1 247-1 259.
Sheu W J, Wu C R, Oey L Y. 2010. Blocking and westward passage of eddies in the Luzon Strait. Deep Sea Research Part Ⅱ:Topical Studies in Oceanography, 57(19-20):1 783-1 791.
Sutyrin G G, Rowe G D, Rothstein L M, Ginis I. 2003.Baroclinic eddy interactions with continental slopes and shelves. Journal of Physical Oceanography, 33(1):283-291.
Van Leeuwen P J. 2007. The propagation mechanism of a vortex on the β plane. Journal of Physical Oceanography, 37(9):2 316-2 330.
Wang G H, Su J L, Chu P C. 2003. Mesoscale eddies in the South China Sea observed with altimeter data. Geophysical Research Letters, 30(21):2 121.
Yuan D L, Han W Q, Hu D X. 2006. Surface Kuroshio path in the Luzon Strait area derived from satellite remote sensing data. Journal of Geophysical Research:Oceans, 111(C11):C11007.
Yuan D L, Wang Z. 2011. Hysteresis and dynamics of a western boundary current flowing by a gap forced by impingement of mesoscale eddies. Journal of Physical Oceanography, 41(5):878-888.
Zheng Q A, Tai C K, Hu J Y, Lin H Y, Zhang Y H, Su F C, Yang X F. 2011. Satellite altimeter observations of nonlinear Rossby eddy-Kuroshio interaction at the Luzon Strait.Journal of Oceanography, 67(4):365-376.