• Aiki, T., Y. Isoda, I. Yabe, and H. Kuroda, 2007: Seasonal variations of surface flow around Toyama Bay (in Japanese with English abstract). Oceanogr. Japan, 16, 291304.

    • Search Google Scholar
    • Export Citation
  • Ardhuin, F., J. M. Pinot, and J. Tintore, 1999: Numerical study of the circulation in a steep canyon off the Catalan coast (western Mediterranean). J. Geophys. Res., 104, 11 11511 135, doi:10.1029/1999JC900029.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bormans, M., and C. Garrett, 1989: A simple criterion for gyre formation by the surface outflow from a strait, with application to the Alboran Sea. J. Geophys. Res., 94, 12 63712 644, doi:10.1029/JC094iC09p12637.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chapman, D. C., 2003: Separation of an advectively trapped buoyancy current at a bathymetric bend. J. Phys. Oceanogr., 33, 11081121, doi:10.1175/1520-0485(2003)033<1108:SOAATB>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Conlon, D. M., 1982: On the outflow modes of the Tsugaru Warm Current. Mer, 20, 6064.

  • Echevin, V., M. Crépon, and L. Mortier, 2003: Interaction of a coastal current with a gulf: Application to the shelf circulation of the Gulf of Lions in the Mediterranean Sea. J. Phys. Oceanogr., 33, 188206, doi:10.1175/1520-0485(2003)033<0188:IOACCW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fukudome, K.-I., J.-H. Yoon, A. Ostrovskii, T. Takikawa, and I.-S. Han, 2010: Seasonal volume transport variation in the Tsushima Warm Current through the Tsushima Straits from 10 years of ADCP observations. J. Oceanogr., 66, 539551, doi:10.1007/s10872-010-0045-5.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fukudome, K.-I., Y. Igeta, T. Senjyu, N. Okei, and T. Watanabe, 2016: Spatiotemporal current variation of coastal-trapped waves west of the Noto Peninsula measured by using fishing boats. Cont. Shelf Res., 115, 113, doi:10.1016/j.csr.2015.12.013.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hanawa, K., and H. Mitsudera, 1985: On the data processing of daily mean values of oceanographical data—Note on daily mean sea level data. Bull. Coastal Oceanogr., 23, 7987.

    • Search Google Scholar
    • Export Citation
  • Hase, H., J.-H. Yoon, and W. Koterayama, 1999: The current structure of the Tsushima Warm Current along the Japanese coast. J. Oceanogr., 55, 217235, doi:10.1023/A:1007894030095.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Igeta, Y., Y. Kitade, and M. Matsuyama, 2005: Numerical experiments on scattering of coastal-trapped waves by topography and bays (in Japanese with English abstract). Oceanogr. Japan, 14, 441458.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Igeta, Y., T. Watanabe, H. Yamada, K. Takayama, and O. Katoh, 2011: Coastal currents caused by superposition of coastal-trapped waves and near-inertial oscillations observed near the Noto Peninsula, Japan. Cont. Shelf Res., 31, 17391749, doi:10.1016/j.csr.2011.07.014.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Joyce, T. M., 1989: On in situ calibration of shipboard ADCPs. J. Atmos. Oceanic Technol., 6, 169172, doi:10.1175/1520-0426(1989)006<0169:OISOSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Katoh, O., K. Morinaga, K. Miyaji, and K. Teshima, 1996: Branching and joining of the Tsushima Current around the Oki Islands. J. Oceanogr., 52, 747761, doi:10.1007/BF02239463.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kawabe, M., 1982: Branching of the Tsushima Current in the Japan Sea. Part I. Data analysis. J. Oceanogr. Soc. Japan, 38, 95107, doi:10.1007/BF02110295.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kida, S., B. Qiu, J. Yang, and X. Lin, 2016: The annual cycle of the Japan Sea Throughflow. J. Phys. Oceanogr., 46, 2339, doi:10.1175/JPO-D-15-0075.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kitade, Y., and M. Matsuyama, 2000: Coastal-trapped waves with several-day period caused by wind along the southeast coast of Honsyu, Japan. J. Oceanogr., 56, 727744, doi:10.1023/A:1011186018956.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Klinck, J. M., 1996: Circulation near submarine canyons: A modelling study. J. Geophys. Res., 101, 12111223, doi:10.1029/95JC02901.

  • Klinger, B. A., 1994a: Baroclinic eddy generation at a sharp corner in a rotating system. J. Geophys. Res., 99, 12 51512 531, doi:10.1029/93JC03585.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Klinger, B. A., 1994b: Inviscid current separation from rounded capes. J. Phys. Oceanogr., 24, 18051811, doi:10.1175/1520-0485(1994)024<1805:ICSFRC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kundu, P. K., J. S. Allen, and R. L. Smith, 1975: Modal composition of velocity fields near the Oregon coast. J. Phys. Oceanogr., 5, 683704, doi:10.1175/1520-0485(1975)005<0683:MDOTVF>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kuroda, H., Y. Isoda, H. Takeoka, and S. Honda, 2006: Coastal current on the eastern shelf of Hidaka Bay. J. Oceanogr., 62, 731744, doi:10.1007/s10872-006-0090-2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mori, K., T. Matsuno, and T. Senjyu, 2005: Seasonal/spatial variations of the near-inertial oscillations in the deep water of the Japan Sea. J. Oceanogr., 61, 761773, doi:10.1007/s10872-005-0082-7.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nakada, S., Y. Isoda, and K. Kusahara, 2003: Response of the coastal branch flow to alongshore variation in shelf topography off Toyama Bay (in Japanese with English abstract). Oceanogr. Japan, 11, 243258.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nakada, S., Y. Isoda, and I. Uchiyama, 2005: Seasonal variations of water properties and the baroclinic flow pattern in Toyama Bay under the influence of the Tsushima Warm Current. J. Oceanogr., 61, 943952, doi:10.1007/s10872-006-0011-4.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nof, D., and T. Pichevin, 2001: The ballooning of outflows. J. Phys. Oceanogr., 31, 30453058, doi:10.1175/1520-0485(2001)031<3045:TBOO>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ohshima, K. I., 1994: The flow system in the Japan Sea caused by a sea level difference through shallow straits. J. Geophys. Res., 99, 99259940, doi:10.1029/94JC00170.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pichevin, T., and D. Nof, 1997: The momentum imbalance paradox. Tellus, 49, 298319, doi:10.3402/tellusa.v49i2.14484.

  • Sanay, R., A. Yankovsky, and G. Voulgaris, 2008: Inner shelf circulation patterns and nearshore flow reversal under downwelling and stratified conditions off a curved coastline. J. Geophys. Res., 113, C08050, doi:10.1029/2007JC004487.

    • Search Google Scholar
    • Export Citation
  • Takikawa, T., J.-H. Yoon, and K.-D. Cho, 2005: The Tsushima Warm Current through Tsushima Straits estimated from ferryboat ADCP data. J. Phys. Oceanogr., 35, 11541168, doi:10.1175/JPO2742.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Watanabe, T., O. Katoh, and H. Yamada, 2006: Structure of the Tsushima Warm Current in the northeastern Japan Sea. J. Oceanogr., 62, 527538, doi:10.1007/s10872-006-0073-3.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yankovsky, A. E., and D. C. Chapman, 1997: Anticyclonic eddies trapped on the continental shelf by topographic irregularities. J. Geophys. Res., 102, 56255639, doi:10.1029/96JC03452.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Transition of the Tsushima Warm Current Path Observed over Toyama Trough, Japan

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  • 1 Japan Sea National Fisheries Research Institute, Fisheries Research and Education Agency, Niigata, Niigata, Japan
  • | 2 School of the Earth, Ocean and Environment, University of South Carolina, Columbia, South Carolina
  • | 3 National Institute of Technology, Toyama College, Imizu, Toyama, Japan
  • | 4 Niigata Prefecture Fisheries and Marine Research Institute, Nishi, Niigata, Japan
  • | 5 Ishikawa Prefecture Fisheries Research Center, Noto, Ishikawa, Japan
  • | 6 Fukui Prefectural Fisheries Experimental Station, Tsuruga, Fukui, Japan
  • | 7 Faculty of Marine Bioscience, Fukui Prefectural University, Obama, Fukui, Japan
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Abstract

Mooring, CTD, and ADCP observations were made in 2012 in and around the Toyama Trough (TT) cutting across a continental shelf along the Japanese coast of the Japan Sea between Noto Peninsula (NP) and Sado Island (SI) to investigate spatiotemporal characteristics of path transition of the coastal branch of the Tsushima Warm Current (CBTWC). Around SI, downstream of the TT boundary, a wavelike alongshore current perturbation, accompanied by sea level rise, was observed. This perturbation occurred after the seasonal amplification of the CBTWC around the NP on the upstream boundary of the TT. This process was delineated by the results of numerical experiments performed with a two-layer model using idealized topography. The model showed that a current path of the CBTWC shifted from alongshore mode to offshore mode bridged over the TT in association with the lee eddy development behind the NP toward the SI over the TT. This lee eddy is generated by positive vorticity induced over topographic discontinuity between the continental shelf off the northern coast of the NP and deeper region of the TT. The model indicated the period of eddy formation is 60–90 days if the volume transport is 1 Sv (1 Sv ≡ 106 m3 s−1), whereas the observations showed the formation period was only 47 days at 1.2 Sv of volume transport. To explain this discrepancy, temporal variation of the CBTWC, vortex supply from preexisting eddies, or eddies caused by the scattering of coastal-trapped waves were suggested as new processes that accelerate the growth rate of the lee eddy.

© 2017 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Yosuke Igeta, igeta@affrc.go.jp

Abstract

Mooring, CTD, and ADCP observations were made in 2012 in and around the Toyama Trough (TT) cutting across a continental shelf along the Japanese coast of the Japan Sea between Noto Peninsula (NP) and Sado Island (SI) to investigate spatiotemporal characteristics of path transition of the coastal branch of the Tsushima Warm Current (CBTWC). Around SI, downstream of the TT boundary, a wavelike alongshore current perturbation, accompanied by sea level rise, was observed. This perturbation occurred after the seasonal amplification of the CBTWC around the NP on the upstream boundary of the TT. This process was delineated by the results of numerical experiments performed with a two-layer model using idealized topography. The model showed that a current path of the CBTWC shifted from alongshore mode to offshore mode bridged over the TT in association with the lee eddy development behind the NP toward the SI over the TT. This lee eddy is generated by positive vorticity induced over topographic discontinuity between the continental shelf off the northern coast of the NP and deeper region of the TT. The model indicated the period of eddy formation is 60–90 days if the volume transport is 1 Sv (1 Sv ≡ 106 m3 s−1), whereas the observations showed the formation period was only 47 days at 1.2 Sv of volume transport. To explain this discrepancy, temporal variation of the CBTWC, vortex supply from preexisting eddies, or eddies caused by the scattering of coastal-trapped waves were suggested as new processes that accelerate the growth rate of the lee eddy.

© 2017 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Yosuke Igeta, igeta@affrc.go.jp
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