Journal of Oceanography

, Volume 68, Issue 2, pp 361–368 | Cite as

Variation of the southward interior flow of the North Pacific subtropical gyre, as revealed by a repeat hydrographic survey

  • Akira Nagano
  • Hiroshi Ichikawa
  • Yasushi Yoshikawa
  • Shoichi Kizu
  • Kimio Hanawa
Short Contribution

Abstract

Baroclinic variations of the southward flow in the interior region of the North Pacific subtropical gyre are presented with five hydrographic sections from San Francisco to near Japan during 2004–2006. The volume transport averaged temperature of the interior flow, which varies vigorously by a maximum of 0.8°C, is negatively correlated with the transport in the layer of density 24.5–26.5σθ, associated with changes in the vertical current structure. Transport variation in this density layer is thus mainly responsible for the thermal impact of the interior flow on the heat transport of the subtropical gyre.

Keywords

North Pacific Subtropical gyre Interior region Volume transport Volume transport averaged temperature 

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Copyright information

© The Oceanographic Society of Japan and Springer 2012

Authors and Affiliations

  • Akira Nagano
    • 1
  • Hiroshi Ichikawa
    • 1
  • Yasushi Yoshikawa
    • 2
  • Shoichi Kizu
    • 3
  • Kimio Hanawa
    • 3
  1. 1.Research Institute for Global ChangeJapan Agency for Marine-Earth Science and TechnologyYokosukaJapan
  2. 2.Mutsu Institute for OceanographyJapan Agency for Marine-Earth Science and TechnologyMutsuJapan
  3. 3.Graduate School of ScienceTohoku UniversitySendaiJapan

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