Ocean Dynamics

, Volume 60, Issue 2, pp 413–426 | Cite as

Why does the Kuroshio northeast of Taiwan shift shelfward in winter?

Article

Abstract

Observations indicate that off the northeastern coast of Taiwan a branch of the Kuroshio intrudes farther northward in winter onto the shelf of the East China Sea. We demonstrate that this seasonal shift can be explained solely by winter cooling. Cooling produces downslope flux of dense shelf water that is compensated by shelfward intrusion. Parabathic isopycnals steepen eastward in winter and couple with the cross-shelf topographic slope (the “JEBAR” effect) to balance the enhanced intrusion. The downslope flow also increases vortex stretching and decreases the thickness of the inertial boundary layer, resulting in a Kuroshio that shifts closer to the shelf break.

Keywords

Kuroshio migration Model simulation Cooling JEBAR 

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Program in Atmospheric and Oceanic SciencesPrinceton UniversityPrincetonUSA
  2. 2.Department of Earth SciencesNational Taiwan Normal UniversityTaipeiTaiwan

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