Abstract
Temporal variations of the Kuroshio volume transport in the Tokara Strait and at the ASUKA line are decomposed by phase-propagating Complex EOF modes of high-resolution sea surface dynamic topography (SSDT) field during the first tandem period of TOPEX/POSEIDON and ERS-1 (from October 1992 to December 1993). Both variations are dominated by a mode with nearly semi-annual cycle, which indicates a series of interactions between the Kuroshio and meso-scale eddies. Namely, northern part of a westward-propagating meso-scale eddy at 23°N is captured into the southern side of the Kuroshio at the south of Okinawa, then it moves downstream along the Kuroshio path passing the Tokara Strait, and reaches to the ASUKA line where it merges with another eddy propagating from the east at 30°N. The variation at the ASUKA line is, however, less dominated by this mode; instead, it includes the SSDT variations in the south of Shikoku and the east of Kyushu which would be directly affected by eddies from the east without passing the Tokara Strait. On the other hand, the same analysis for movements of the Kuroshio axis in the Strait indicates that they are governed by short-term variations locally confined to the Kuroshio in the East China Sea without being induced by meso-scale eddies. This results, however, seem to depend strongly on a time scale of interest. It is suggested that the long-term movements of the Kuroshio axis in the Strait would demonstrate coincidence with SSDT variation in the south of Japan.
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References
Akitomo, K., T. Awaji and N. Imasato (1991): Kuroshio path variation south of Japan 1. Barotropic inflow-outflow model. J. Geophys. Res., 96(C2), 2549-2560.
Akitomo, K., M. Ooi, T. Awaji and K. Kutsuwada (1996): Interannual variability of the Kuroshio transport in response to the wind stress field over the North Pacific: Its relation to the path variation south of Japan. J. Geophys. Res., 101(C6), 14,057-14,071.
Akitomo, K., S. Masuda and T. Awaji (1997): Kuroshio path variation south of Japan: Stability of the paths in a multiple equilibrium regime. J. Oceanogr., 53, 129-142.
AVISO (1996): AVISO Handbook for Merged TOPEX/POSEIDON Products, AVI-NT-02-101-CN, Edition 3.0.
Barnet, T. P. (1983): Interaction of the monsoon and Pacific trade wind system at interannual time scales. Part I: The equatorial zone. Mon. Wea. Rev., 111, 756-773.
Ebuchi, N. and K. Hanawa (2000): Mesoscale eddies observed by TOLEX-ADCP and TOPEX/POSEIDON altimeter in the Kuroshio recirculation region south of Japan. J. Oceanogr., 56, 43-57.
Emery, W. J., W. G. Lee and L. Magaard (1984): Geographic and seasonal distributions of Brunt-Väisälä frequency and Rossby radii in the North Pacific and North Atlantic. J. Phys. Oceranogr., 14, 294-317.
Feng, M., H. Mitsudera and Y. Yoshikawa (2000): Structure and variability of Kuroshio current at the Tokara Strait. J. Phys. Oceranogr. (in press).
Hanawa, K. and H. Mitsudera (1985): On the data processings of daily mean values of oceanographical data—Note on daily mean sea-level data—. Bull. Coast. Oceanogr., 23, 79-87 (in Japanese).
Ichikawa, H. and R. C. Beardsley (1993): Temporal and spatial variability of volume transport of the Kuroshio in the East China Sea. Deep-Sea Res. I, 40, 583-605.
Ichikawa, K. and S. Imawaki (1994): Life history of a cyclonic ring detached from the Kuroshio Extension as seen by the Geosat altimeter. J. Geophys. Res., 99(C8), 15953-15966.
Ichikawa, K. and S. Imawaki (1996): Estimating the sea surface dynamic topography from Geosat altimetry data. J. Oceanogr., 52, 43-68.
Ichikawa, K. and A. Kaneda (2001): Coastal impacts of offshore meso-scale eddies through the Kuroshio variation. La mer (in press).
Imawaki, S., H. Uchida, H. Ichikawa, M. Fukasawa, S. Umatani and ASUKA group (1997): Time series of the Kuroshio transport derived from field observations and altimetry data. Int. WOCE Newsletter, 25, 15-18.
Kawabe, M. (1995): Variations of current path, velocity and volume transport of the Kuroshio in relation with the large meander. J. Phys. Oceranogr., 25, 3103-3117.
Koshlyakov, M. N. (1986): Eddies of western boundary currents. p. 208-376. In Synoptic Eddies in the Ocean, ed. by V. M. Kamenkovich, M. N. Koshlyakov and A. S. Monin, D. Reidel, Norwell, Mass.
Le Traon, P. Y. and F. Ogor (1998): ERS-1/2 orbit improvement using TOPEX/POSEIDON: the 2 cm challenge. J. Geophys. Res., 103(C4) 8045-8057.
Le Traon, P. Y., P. Gaspar, F. Bouyssel and H. Makhmara (1995): Using TOPEX/POSEIDON data to enhance ERS-1 data. J. Atmos. Ocean. Tech., 12, 161-170.
Lie, H.-J., C.-H. Cho, J.-H. Lee, P. Niiler and J.-H. Hu (1998): Separation of the Kuroshio water and its penetration onto the continental shelf west of Kyushu. J. Geophys. Res., 103(C2), 2963-2976.
Masuda, A. (1982): An interpretation of the bimodal character of the stable Kuroshio path. Deep-Sea Res. Part A, 29, 471-484.
Masuda, S., K. Akitomo and T. Awaji (1999): Effect of stratification and bottom topography on the Kuroshio path variation south of Japan. Part I: Dependence of the path selection on velocity. J. Phys. Oceranogr., 29, 2419-2431.
Nagata, Y. and K. Takeshita (1985): Variation of the sea surface temperature distribution across the Kuroshio in the Tokara Strait. J. Oceanogr. Soc. Japan, 41, 244-258.
Qiu, B., T. Toda and N. Imasato (1990): On Kuroshio fluctuations in the East China Sea using satellite and in situ observational data. J. Geophys. Res., 95(C10), 18191-18204.
Richardson, P. L. (1983): Gulf Stream rings. p. 19-45. In Eddies in Marine Science, ed. by A. R. Robinson, Springer-Verlag, New York.
White, W. B. and J. P. McCreary (1976): On the formation of the Kuroshio meander and its relationship to the large-scale ocean circulation. Deep-Sea Res., 23, 33-47.
White, W. B., S. E. Pazan and M. Inoue (1987): Hindcast/Forecast of ENSO events based upon the redistribution of observed and model heat content in the western tropical Pacific, 1964–86. J. Phys. Oceranogr., 17, 264-280.
Yasuda, I., J.-H. Yoon and N. Suginohara (1985): Dynamics of the Kuroshio large meander—Barotropic model. J. Oceanogr. Soc. Japan, 41, 259-273.
Yasuda, I., K. Okuda and M. Hirai (1992): Evolution of a Kuroshio warm-core ring: Variability of the hydrographic structure. Deep-Sea Res. Part A, 39,Suppl. I, S131-S161.
Yasuda, I., S. Itoh, Y. Shimizu, K. Ichikawa, K. Ueda, T. Honma, M. Uchiyama, K. Watanabe, N. Suno, K. Tanaka and K. Koizumi (2000): Cold-core anti-cyclonic eddies south of Bussol' Strait in the north-western Subarctic Pacific. J. Phys. Oceranogr., 30, 1137-1157.
Yoon, J.-H. and I. Yasuda (1987): Dynamics of the Kuroshio large meander: Two-layer model. J. Phys. Oceranogr., 17, 66-81.
Zhang, D., T. N. Lee, W. E. Johns, C.-T. Liu and R. Zantopp (2000): The Kuroshio east of Taiwan—Modes of variability and relationship to interior ocean meso-scale eddies. J. Phys. Oceranogr. (submitted).
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Ichikawa, K. Variation of the Kuroshio in the Tokara Strait Induced by Meso-Scale Eddies. Journal of Oceanography 57, 55–68 (2001). https://doi.org/10.1023/A:1011174720390
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DOI: https://doi.org/10.1023/A:1011174720390