Journal of Oceanography

, Volume 68, Issue 4, pp 521–531 | Cite as

Low-frequency variations of the Eastern Subtropical Front in the North Pacific in an eddy-resolving ocean general circulation model: roles of central mode water in the formation and maintenance

  • Shusaku Sugimoto
  • Kimio Hanawa
  • Tamaki Yasuda
  • Goro Yamanaka
Original Article


Temporal variations (1960–2005) of the Eastern Subtropical Front (ESTF) in the North Pacific are investigated using historical-run output data of the eddy-resolving Meteorological Research Institute Community Ocean Model, forced by atmospheric reanalysis dataset. Simulated ESTF is distributed in a region of zonal band of 24°N–30°N east of the International Date Line, and is located at the southern boundary of the central mode water (CMW) north of the front. The ESTF intensity clearly shows an interdecadal variation with a timescale of about 20 years. This variation is associated with that in the potential vorticity of CMW, which originates in the CMW formation region farther north about 3 years earlier due to changes in the surface wind forcing.


Subtropical front Central mode water Mixed layer Decadal timescale 



The authors wish to express their sincere thanks to Dr. Eitarou Oka and the members of the Physical Oceanography Group at Tohoku University for their useful discussion. Comments and suggestions from the editor and anonymous reviewer were very helpful for the improvement of this paper. The first author (S.S.) was supported by the Grant-in-Aid for Young Scientists (B) (No. 23740348) from the Japan Society for the Promotion of Science and partly by the Grant-in-Aid for Scientific Research on Innovative Areas (23106501, “A ‘hot spot’ in the climate system: Extra-tropical air-sea interaction under the East Asian monsoon system”) from the Ministry of Education, Culture, Sports, Science, and Technology.


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Copyright information

© The Oceanographic Society of Japan and Springer 2012

Authors and Affiliations

  • Shusaku Sugimoto
    • 1
  • Kimio Hanawa
    • 1
  • Tamaki Yasuda
    • 2
  • Goro Yamanaka
    • 3
  1. 1.Department of Geophysics, Graduate School of ScienceTohoku UniversitySendaiJapan
  2. 2.Climate Research DepartmentMeteorological Research Institute 1-1 NagamineTsukubaJapan
  3. 3.Oceanographic Research DepartmentMeteorological Research Institute 1-1 NagamineTsukubaJapan

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