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Simulation of Formation and Spreading of Salinity Minimum Associated with NPIW Using a High-Resolution Model

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Abstract

A series of numerical experiments were conducted with a high-resolution (eddy-permitting) North Pacific model to simulate the formation and spreading of the salinity minimum associated with the North Pacific Intermediate Water (NPIW). It was found that two factors are required to simulate a realistic configuration of the salinity minimum: a realistic wind stress field and small-scale disturbances. The NCEP reanalyzed wind stress data lead to better results than the Hellerman and Rosenstein wind stress data, due to the closer location of the simulated Oyashio and Kuroshio at the western boundary. Small-scale disturbances formed by relaxing computational diffusivity included in the advection scheme promote the large-scale isopycnal mixing between the Oyashio and Kuroshio waters, simulating a realistic configuration of the salinity minimum. A detailed analysis of the Oyashio water transport was carried out on the final three-year data of the experiment with reduced computational diffusivity. Simulated transport of the Kuroshio Extension in the intermediate layer is generally smaller than the observed value, while those of the Oyashio and the flow at the subarctic front are comparable to the observed levels. In the Oyashio-Kuroshio interfrontal zone the zonally integrated southward transport of the Oyashio water (140–155°E) is borne by the eddy activity, though the time-mean flow reveals the existence of a coastal Oyashio intrusion. In the eastern part (155°E–180°) the zonally integrated transport of the Oyashio water indicates a southward peak at the southern edge of the Kuroshio Extension, which corresponds to the branching of the recirculating flow from the Kuroshio Extension.

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References

  • Bryan, K. and L. J. Lewis (1979): A water mass model of the world ocean. J. Geophys. Res., 84, 2503–2517.

    Google Scholar 

  • Gent, P. R. and J. McWilliams (1990): Isopycnal mixing in ocean general circulation models. J. Phys. Oceanogr., 20, 150–155.

    Article  Google Scholar 

  • Gent, P. R., T. Willebrand, T. McDougall and J. McWilliams (1995): Parameterizing eddy-induced tracer transports in ocean circulation models. J. Phys. Oceanogr., 25, 463–474.

    Article  Google Scholar 

  • Hasunuma, K. (1978): Formation of the intermediate salinity minimum in the northwestern Pacific Ocean. Bull. Ocean. Res. Inst., Univ. of Tokyo, 9, 1–47.

    Google Scholar 

  • Hellerman, S. and M. Rosenstein (1983): Normal monthly wind stress over the World Ocean with error estimates. J. Phys. Oceanogr., 13, 1093–1104.

    Article  Google Scholar 

  • Holland, W. R., J. C. Chow and F. O. Bryan (1998): Application of a third-order upwind scheme in the NCAR ocean model. J. Climate, 11, 1487–1493.

    Article  Google Scholar 

  • Hurlburt, H. E., A. J. Wallcraft, W. J. Schmitz, Jr., P. J. Hohan and E. J. Metzger (1996): Dynamics of the Kuroshio/ Oyashio current system using eddy-resolving models of the North Pacific Ocean. J. Geophys. Res., 101, 941–976.

    Article  Google Scholar 

  • Ishizaki, H. and T. Motoi (1999): Reevaluation of Takano-Oonishi scheme for momentum advection on bottom relief in ocean models. J. Atmos. Ocean. Tech., 16, 1994–2010.

    Article  Google Scholar 

  • Iwao, T., M. Endoh, N. Shikama and T. Nakano (2003): Intermediate circulation in the northwestern North Pacific derived from subsurface floats. J. Oceanogr., 59, 893–904.

    Article  Google Scholar 

  • Kawai, H. (1972): Hydrography of the Kuroshio and the Oyashio. p. 129–320. In Physical Oceanography II, Fundamental Lectures of Oceanography, ed. by M. Iwashita et al., Tokai University Press (in Japanese).

  • Kawamura, H., K. Mizuno and Y. Toba (1986): Formation process of a warm-core ring in the Kuroshio-Oyashio frontal zone-December 1981-October 1982. Deep-Sea Res., 33, 1617–1640.

    Article  Google Scholar 

  • Kawasaki, Y. (1992): Processes of modification and decay of the Kuroshio warm-core ring 86B in the North Pacific western Subarctic Region. Bull. Hokkaido Natl. Fish. Res. Inst., 56, 43–53 (in Japanese).

    Google Scholar 

  • Kobayashi, T. (1999): Study of the formation of North Pacific Intermediate Water by a general circulation model and the particle-tracking method 1. A pitfall of general circulation model studies. J. Geophys. Res., 104, 5423–5439.

    Article  Google Scholar 

  • Kobayashi, T. (2000): Study of the formation of North Pacific Intermediate Water by a general circulation model and the particle-tracking method 2. Formation mechanism of salinity minimum from the view of the "critical gradient" of the Oyashio mixing ratio. J. Geophys. Res., 105, 1055–1069.

    Article  Google Scholar 

  • Kono, T. (1997): Modification of the Oyashio Water in the Hokkaido and Tohoku areas. Deep-Sea Res. I, 44, 669–688.

    Article  Google Scholar 

  • Kono, T. (1998): Formation of the salinity minimum in the Mixed Water Region between the Oyashio and Kuroshio Fronts. Deep-Sea Res. I, 45, 2035–2057.

    Article  Google Scholar 

  • Kono, T., Y. Kawasaki, A. Kusaka, T. Takizawa and M. Wakatushi (2003): Time change of water properties in Bussol Strait in the Kuril Islands and southeast coast of Hokkaido. J. Oceanogr. (submitted).

  • Lee, M.-M., A. C. Coward and A. J. G. Nurser (2002): Spurious diapycnal mixing of the deep waters in an eddy-permitting global ocean model. J. Phys. Oceanogr., 32, 1522–1535.

    Article  Google Scholar 

  • Levitus, S., R. Burgett and T. Boyer (1994): World Ocean Atlas 1994. NOAA Atlas NESDIS 3 and 4, U.S. Dep. Comm., Washington, D.C.

    Google Scholar 

  • Miyao, T. and K. Ishikawa (2003): Formation, distribution and volume transport of the North Pacific Intermediate Water studied by repeat hydrographic observations. J. Oceanogr., 59, 905–919.

    Article  Google Scholar 

  • Nakamura, T., T. Toyoda, Y. Ishikawa and T. Awaji (2004): Tidal mixing in the Kuril Straits and its impact on ventilation in the North Pacific Ocean. J. Oceanogr., 60, this issue, 411–423.

    Article  Google Scholar 

  • Okuda, K., K. Segawa and Y. Hiroe (1995): Observational study in the region of the Kuroshio Extension. J-WOCE Report, 187–204, Japan Science Tech. Agency (in Japanese).

  • Okuda, K., I. Yasuda, Y. Hiroe and Y. Shimizu (2001): Structure of subsurface intrusion of the Oyashio Water into the Kuroshio Extension and formation process of the North Pacific Intermediate Water. J. Oceanogr., 57, 121–140.

    Article  Google Scholar 

  • Shimizu, Y., I. Yasuda and S. Ito (2001): Distriution and circulation of the coastal Oyashio intrusion. J. Phys. Oceanogr., 31, 1561–1578.

    Article  Google Scholar 

  • Shimizu, Y., I. Yasuda, K. Okuda, K. Hanawa and S. Ito (2003): ADCP-referenced Kuroshio and Oyashio water transports for North Pacific Intermediate Water formation. J. Phys. Oceanogr., 33, 220–233.

    Article  Google Scholar 

  • Talley, L. D. (1993): Distribution and formation of North Pacific Intermediate Water. J. Phys. Oceanogr., 23, 517–537.

    Article  Google Scholar 

  • Talley, L. D., Y. Nagata, M. Fujimura, T. Iwao, T. Kono, D. Inagake, M. Hitai and K. Okuda (1995): North Pacific Intermediate Water in the Kuroshio/Oyashio mixed water region. J. Phys. Oceanogr., 25, 475–501.

    Article  Google Scholar 

  • Webb, D. J., B. A. De Cuevas and C. S. Richmond (1998): Improved advection scheme for ocean models. J. Atmos. Ocean. Tech., 151171–1187.

    Article  Google Scholar 

  • Yamanaka, G., Y. Kitamura and M. Endoh (1998a): Formation of North Pacific Intermediate Water in Meteorological Research Institute ocean generalcirculation model 1. Subgrid scale mixing and marginal sea fresh water. J. Geophys. Res., 103, 30885–30903.

    Article  Google Scholar 

  • Yamanaka, G., Y. Kitamura and M. Endoh (1998b): Formation of North Pacific Intermediate Water in Meteorological Research Institute ocean generalcirculation model 2. Transient tracer experiment. J. Geophys. Res., 103, 30905–30921.

    Article  Google Scholar 

  • Yang, S.-K. and Y. Nagata (1990): The properties of the Intermediate Layer Water in the adjacent seas of Japan. Umi to Sora, 66, 65–74 (in Japanese with English abstract).

    Google Scholar 

  • Yasuda, I. (1997): The origin of the North Pacific Intermediate Water. J. Geophys. Res., 102, 893–909.

    Article  Google Scholar 

  • Yasuda, I., K. Okuda and M. Hirai (1992): Evolution of a Kuroshio warm-core ring-variability of the hydrographic structure. Deep-Sea Res., 39, Suppl. 1, S131–S161.

    Google Scholar 

  • Yasuda, I., K. Okuda and Y. Shimizu (1996): Distribution and modification of North Pacific Intermediate Water in the Kuroshio-Oyashio Interfrontal Zone. J. Phys. Oceanogr., 26, 448–465.

    Article  Google Scholar 

  • Yasuda, I., S. Ito, Y. Shimizu, K. Ichikawa, K. Ueda, T. Honma, M. Uchiyama, K. Watanabe, N. Sunou, K. Tanaka and K. Koizumi (2000): Cold-core anticyclonic eddies south of Bussol' Strait in the northwestern subarctic Pacific. J. Phys. Oceanogr., 30, 1137–1157.

    Article  Google Scholar 

  • Yasuda, I., Y. Hiroe, K. Komatsu, K. Kawasaki, T. M. Joyce, F. Bahr and Y. Kawasaki (2001): Hydrographic structure and transport of the Oyashio south of Hokkaido and the formation of the North Pacific Intermediate Water. J. Geophys. Res., 106, 6931–6942.

    Article  Google Scholar 

  • Zhang, R.-C. and K. Hanawa (1993): Features of the watermass front in the northwestern North Pacific. J. Geophys. Res., 98, 967–975.

    Article  Google Scholar 

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Authors and Affiliations

  1. Meteorological Research Institute, Nagamine, Tsukuba, Ibaraki, 305-0052, Japan

    Hiroshi Ishizaki & Ichiro Ishikawa

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  1. Hiroshi Ishizaki
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  2. Ichiro Ishikawa
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Correspondence to Hiroshi Ishizaki.

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Ishizaki, H., Ishikawa, I. Simulation of Formation and Spreading of Salinity Minimum Associated with NPIW Using a High-Resolution Model. Journal of Oceanography 60, 463–485 (2004). https://doi.org/10.1023/B:JOCE.0000038382.70748.f2

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