Journal of Oceanography

, Volume 49, Issue 6, pp 667–682 | Cite as

TheKyucho in Sukumo Bay induced by Kuroshio warm filament intrusion

  • Hideki Akiyama
  • Sei-ichi Saitoh
Article

Abstract

Surface temperature data obtained in and out of the bay all year round from March 1990 through February 1991, except from July through October 1990 were analyzed to investigate seasonal variability of theKyucho in Sukumo Bay, southwest of Shikoku, Japan. TheKyucho periodically occurs in the bay during both the warming period of March through June and the cooding period of November through February. The onset period of theKyucho is 8–15 days during the warming period and 4–14 days during the cooling period, giving an average of about 10 and 8 days, respectively. The position of the Kuroshio axis offshore in the south of Cape Ashizuri-misaki is a significant factor with theKyucho in the bay. Thermal infrared images taken by the NOAA-11 in the sea off east of Kyushu were also analyzed during the two observation periods. It is clearly found that a warm filament derived from the Kuroshio (KWF) advects northeast to Cape Ashizurimisaki along the Kuroshio, then encounters the southwest coast of Shikoku, followed by inducing theKyucho in the bay by the warm water intrusion. The alongshelf dimension of the KWFs is approximately 50–100 km, and the cross-shelf distance from the western edge of the KWFs to that of the body of the east Kuroshio is about 30–50 km. The KWF sometimes closely approaches to the east coast of Kyushu. An onshore meander of the Kuroshio front around Cape Toimisaki might grow into a KWF in the sea off east of Kyushu.

Keywords

Japan Surface Temperature Temperature Data East Coast Warm Water 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Akiyama, H. (1991): TheKyucho in Sukumo Bay.Bull. Coast. Oceangr.,29, 90–96 (in Japanese with English abstract).Google Scholar
  2. Akiyama, H. and T. Yanagi (1984): The mechanism of the sudden change of water temperature in Sukumo Bay.Bull. Coast. Oceangr.,22, 61–66 (in Japanese).Google Scholar
  3. Akiyama, H. and T. Yanagi (1990): Seasonal variation in water distribution off Cape of Toi.Umi to Sora,65, 267–283 (in Japanese with English abstract).Google Scholar
  4. Akiyama, H., T. Yanagi and K. Nakata (1987): Sudden change of water temperature during summer in Sukumo Bay.Bull. Coast. Oceangr.,24, 169–181 (in Japanese).Google Scholar
  5. Akiyama, H., Y. Ohno and S. Saitoh (1992): Kuroshio warm filament passing around the Tokara Strait.Umi to Sora,68, 99–112 (in Japanese with English abstract).Google Scholar
  6. Awaji, T., K. Akitomo and N. Imasato (1991): Numerical study of shelf water motion driven by the Kuroshio: barotropic model.J. Phys. Oceanogr.,21, 11–27.Google Scholar
  7. Bane, J. M., Jr., D. A. Brooks and K. R. Lorenson (1981): Synoptic observation of the three-dimensional structure and propagation of Gulf Stream meanders along the Carolina continental marginJ. Geophys. Res.,86, 6411–6425.Google Scholar
  8. Emery, W. J., A. C. Thomas, M. J. Collins, W. R. Crawford and D. L. Mackas (1986): An objective method for computing advective surface velocities from sequential infrared satellite images.J. Geophys. Res.,91, 12865–12878.Google Scholar
  9. Japan Fisheries Agency, Ooita, Miyazaki, and Kagoshima Prefectural Fisheries Experimental Stations (1978):Technical Report of Fisheries Ecology and Its Nursery Ground Formation in the Coastal Seas, Southwest of Japan. 562 pp. (in Japanese).Google Scholar
  10. Kawai, H. (1972): Oceanography of the Kuroshio and the Oyashio. p. 129–321. InPhysical Oceanography II Tokai Univ. Press (in Japanese).Google Scholar
  11. Kawai, H. (1991): Structures of the currents as an environment of fisheries. p. 2–51. InCurrents and Fisheries-Special Lectures on Fisheries Oceanography, Kyoto Univ. Press (in Japanese).Google Scholar
  12. Kimura, K. (1942): On “Dai Kyucho” along the coasts.Chuo Kishodai Iho,19, 1–85 (in Japanese).Google Scholar
  13. Kimura, S. and T. Sugimoto (1990): Intrusion processes of warm water mass from the Kuroshio into the coastal area of Kumano-nada and Enshu-nada seas.Bull. Japan. Soc. Fish. Oceanogr.,54, 19–31 (in Japanese with English abstract).Google Scholar
  14. Kunishi, H., K. Nishi and T. Suzuki (1968): Some observations on coastal processes in Tanabe Bay (II).Disaster Prev. Res. Inst. Annu. Kyoto Univ.,11B, 327–335 (in Japanese).Google Scholar
  15. Lee, T. N., L. P. Atkinson and R. Legeckis (1981): Observation of a Gulf Stream frontal eddy on the Georgia continental shelf, April 1977.Deep-Sea Res.,28, 347–378.Google Scholar
  16. Luther, M. E. and J. M. Bane, Jr. (1985): Mixed instabilities in the Gulf Stream over the continental slope.J. Phys. Oceanogr.,15, 3–23.Google Scholar
  17. Matsuyama, M. and S. Iwata (1977): TheKyucho in Sagami Bay (I)-theKyucho observed in 1975.Bull. Japan. Soc. Fish. Oceanogr.,30, 1–7 (in Japanese).Google Scholar
  18. Miyaji, K. (1991): Studies on the eddies associated with the meander of the Kuroshio in the waters off southwest coast of Kyushu and their effects on egg and larval transport.Bull. Seikai Nat. Fish. Res. Inst.,69, 1–77 (in Japanese with English abstract).Google Scholar
  19. Oey, L.-Y. (1988): A model of Gulf Stream frontal instabilities, meanders and eddies along the continental slope.J. Phys. Oceanogr.,18, 211–229.Google Scholar
  20. Orlanski, I. (1969): The influence of bottom topography on the stability of jets in a baroclinic fluid.J. Atmos. Sci.,26, 1216–1232.Google Scholar
  21. Pietrafesa, L. J. (1983): Survey of a Gulf Stream frontal filament.Geophys. Res. Lett.,10, 203–206.Google Scholar
  22. Qiu, B., T. Toda and N. Imasato (1990): On Kuroshio front fluctuations in the East China Sea usingin situ observational data.J. Geophys. Res.,95, 18191–18204.Google Scholar
  23. Sakamoto, H. (1971): Some behaviors of a warm filament around the southwest coast of Japan. p. 56–59. InTechnical Report of the Prompt Oceanographic Observation in the Seas, Southwest of Japan, ed. by Japan Fish. Agency and Nansei, Nat. Fish. Res. Inst. (in Japanese).Google Scholar
  24. Takeoka, H. (1990): Physical environment of the sea of Uwa as a ground of marine culture.Bull. Japan. Soc. Fish. Oceanogr.,54, 9–18 (in Japanese with English abstract).Google Scholar
  25. Takeoka, H. and T. Yoshimura (1988): TheKyucho in Uwajima Bay.J. Oceanogr. Soc. Japan,44, 6–16.Google Scholar
  26. Takeuchi, J. (1989): Warm water intrusion in the southern area of Kumano-nada.Bull. Japan. Soc. Fish. Oceanogr.,53, 242–254 (in Japanese with English abstract).Google Scholar
  27. Tanaka, Y., J. Shinohara and R. Tsuda (1992): TheKyucho in Uragami Bay.Bull. Coast. Oceangr.,30, 37–44 (in Japanese with English abstract).Google Scholar
  28. Toda, T. (1993): Movement of the surface front induced by Kuroshio frontal eddy.J. Geophys. Res. (in press).Google Scholar
  29. Toda, T., K. Nakano, K. Nishi, N. Imasato and H. Kunishi (1988): Time series analysis of oceanic fronts using satellite imagery: methods and examples.Sora to Umi,10, 1–16 (in Japanese with English abstract).Google Scholar
  30. Uda, M. (1953): On the Stormy Current (“Kyutyo”) and its prediction in the Sagami Bay. I.J. Oceanogr. Soc. Japan,9, 15–22 (in Japanese with English abstract).Google Scholar
  31. Uda, M. (1984):Oral Traditions in Seas and Fisheries. Tamagawa Univ. Press, 392 pp. (in Japanese).Google Scholar
  32. Vukovich, F. M. and B. W. Crissman (1980): Some aspects of Gulf Stream western boundary eddies from satellite andin situ data.J. Phys. Oceanogr.,10, 1792–1813.Google Scholar
  33. Yokota, T. (1953): Studies on the Sardines in Hyuga-nada and Bungo-Strait.Bull. Nankai Nat. Fish. Res. Inst.,2, 1–251 (in Japanese).Google Scholar
  34. Yousho, F. (1971): Variation of the Kuroshio axis and the migration of warm filaments. p. 49–51. InTechnical Report of the Prompt Oceanographic Observation in the Seas, Southwest of Japan, ed. by Japan Fish. Agency and Nansei Nat. Fish. Res. Inst. (in Japanese).Google Scholar
  35. Zantopp, R., K. D. Leaman and T. N. Lee (1987): Florida Current meanders: a close look in June–July 1984.J. Phys. Oceanogr.,17, 584–595.Google Scholar

Copyright information

© Journal of the Oceanographic Society of Japan 1993

Authors and Affiliations

  • Hideki Akiyama
    • 1
  • Sei-ichi Saitoh
    • 2
  1. 1.Department of Civil and Ocean EngineeringEhime UniversityMatsuyamaJapan
  2. 2.Meteorological Information CenterJapan Weather AssociationTokyoJapan

Personalised recommendations