Journal of Oceanography

, Volume 56, Issue 3, pp 275–294 | Cite as

POM and Two-Way Nesting POM Study of Kuroshio Damping Phenomenon Caused by a Strong Wind

  • Yasumasa Miyazawa
  • Shinya Minato
Article

Abstract

A Kuroshio damping phenomenon of a few days scale caused by a strong wind was studied using the Princeton Ocean Model (POM) and a two-way nesting model for the POM. We simulated an idealized eastward Kuroshio in a zonal channel in terms of the inflow/outflow condition at the western/eastern boundaries and examined responses of the idealized Kuroshio to a strong easterly wind. This study was motivated by observations of JMA research vessel Shumpu Maru which reported deformation of isopycnals and damping of the Kuroshio before and after the attack of Typhoon 6804. Deformation of isopycnals and damping of the Kuroshio are found to depend on magnitude of wind stress, intensity of stratification, distance of the Kuroshio from coast, and grid resolution. The deformation of isopycnals is related to the vertical circulation pattern caused by the divergence/convergence of the onshore Ekman transport. A simple stratification model composed of Niiler (1969)'s modification of the Ekman transport and the coastal boundary is proposed to explain the damping phenomenon. An idealized cape was added in other experiments in order to study whether the Kuroshio damping mechanism discussed here works in three dimensions. The newly developed two-way nesting model for the POM was applied for this experiment and made it possible to clarify more detailed features of response in the nested area than did the coarse grid model.

Kuroshio strong wind stress downwelling/upwelling Niiler cell POM nesting 

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References

  1. Blumsack, S. L. (1972): The transverse circulation near a coast. J. Phys. Oceanogr., 2, 34–40.Google Scholar
  2. Kurihara, Y. and M. A. Bender (1980): Use of a movable nested-mesh model for tracking a small vortex. Mon. Wea. Rev., 108, 1792–1809.Google Scholar
  3. Large, W. G. and S. Pond (1981): Open ocean momentum flux measurements in moderate to strong winds. J. Phys. Oceanogr., 11, 324–336.Google Scholar
  4. Lee, D.-K., P. P. Niiler, A. Warn-Varnas and S. Piacsek (1994): Wind-driven secondary circulation in ocean mesoscale. J. Mar. Res., 52, 371–396.Google Scholar
  5. Mellor, G. L. (1991): An equation of state for numerical models of oceans and estuaries. J. Atmos. Oceanic Tech., 8, 609–611.Google Scholar
  6. Mellor, G. L. (1996): Users guide for a three-dimensional, primitive equation, numerical ocean model. Princeton University.Google Scholar
  7. Mellor, G. L. and T. Yamada (1982): Development of a turbulence closure model for geophysical fluid problems. Rev. Geophys. Space Phys., 20, 851–875.Google Scholar
  8. Niiler, P. P. (1969): On the Ekman divergence in an oceanic jet. J. Geophys. Res., 74, 7048–7052.Google Scholar
  9. Oey, L.-Y. (1986): The formation and maintenance of density fronts on the U.S. southeastern continental shelf during winter. J. Phys. Oceanogr., 16, 1121–1135.Google Scholar
  10. Oey, L.-Y. (1996): Flow around a coastal bend: A model for the Santa Barbara Channel eddy. J. Geophys. Res., 101, 16667–16682.Google Scholar
  11. Oey, L.-Y. and P. Chen (1992): A nested-grid ocean model: with application to the simulation of meanders and eddies in the Norwegian coastal current. J. Geophys. Res., 97, 20063–20086.Google Scholar
  12. Shuto, K. (1978): Effects of wind stress and bottom topography on the Kuroshio. Marine Sciences/quarterly, 1,No. 2, 46–52 (in Japanese).Google Scholar
  13. Spall, M. A. and W. R. Holland (1991): A nested primitive equation model for oceanic applications. J. Phys. Oceanogr., 21, 205–220.Google Scholar
  14. Sugie, H., A. Okazaki, Y. Adachi and M. Ozaki (1985): Numerical Calculation Methods by Fortran77. Baihukan, Tokyo, 122 pp. (in Japanese).Google Scholar
  15. Xue, H. and J. M. Bane, Jr. (1997): A numerical investigation of the Gulf Stream and its meanders in response to cold air outbreaks. J. Phys. Oceanogr., 27, 2606–2629.Google Scholar
  16. Xue, H., J. M. Bane, Jr. and L. M. Goodman (1995): Modification of the Gulf Stream through strong air-sea interactions in winter: observations and numerical simulations. J. Phys. Oceanogr., 25, 533–557.Google Scholar
  17. Yoshida, K. (1955): Coastal upwelling off the California coast. Rec. Oceanogr. Wks. Japan, New Ser., 2, 8–20.Google Scholar
  18. Zhang, D. L., H. R. Chang, N. L. Seaman, T. T. Warner and J. M. Fritsch (1986): A two-way interactive nesting procedure with variable terrain resolution. Mon. Wea. Rev., 114, 1330–1339.Google Scholar

Copyright information

© The Oceanographic Society of Japan 2000

Authors and Affiliations

  • Yasumasa Miyazawa
    • 1
  • Shinya Minato
    • 2
  1. 1.Institute for Global Change Research/FRSGCTokyoJapan
  2. 2.Meteorological Research InstituteIbarakiJapan

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