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5% 26;i3 5% 5 Wl1995 "f 9 JJ

#i 1$ 1=3 ffi] mOCEANOLOGIA ET LIMNOLOGIA SINICA

Vol. 26, No.5

Sep., 1995

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Fig.1 Distribution of x and y(path) for thefirst" kind of boundary condition

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:y.J\mJ>jZ,:EJG~,'lltJa.f4,1987 ,~iililr'Uftf,l:*~iiIE~(~~)rt-J1JJZI75HIT,~iililU\HltiQ;)(~(- ),iliii$tl:\llIHt(;ft:ll'O,1-140

Masuda, A., 1982, An interpretation of the bimodal character of the stable kuroshio path, Deep SeaRes., 29:471-484.

Robinson, A. K. e t aL, 1975, On the theory of thin rotating jets: a quasigeostrophisic time dependa-nt model, Geopb: Fluid Dyn., 6:211-244.

Robinson, A. R. and Niiler, P. P., 1967, The theory of free intertial currents L path and structure,T'e ll us , 19:269-291.' .

Robinson, A. R. and Taft, B. A., 1972; A numerical Experiment for the Path of the Kuroshio, J.Mar. Res., 30:65-101.

ON FURTHER APPLICATION OF THE THIN-JET MODELINTO THE BIMODALITY OF KUROSHIO

Dong Changming, Zhang Qinghua(First Institute of Oceanography, SOA, Qingdao 266003)

ABSTRACT

Flowing in a semi-enclosed sea, the Kuroshio south of Japan is a jet forced byIsu Islands downstream. Based on Masuda's work, the present paper discusses two

kinds of boundary conditions, .d6 I = ko and 6 I r=o = 60, for the path curves,studyds ,~o

of which' show that the second one is more resonable than the first one. Comparisonof the results with the force of Isu Islands and with no force downstream revealsthat attribution of Isu Islands as the downstream external forece leading to the fo-rmation of the bimodality is important. The results of study on the above two aspe-cts reflect that both the local factor and nonlinearity exert important effects on theformation of the bimodality of the Kuroshio south of Japan.

Key words Bimodality Local factor