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»Sc.D. Thesis
»Recirculation gyres in a beta-plane jet
»Forcing and sampling of ocean models
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»Recirculation forced by an unstable jet
»Tidal dissipation over rough topography
»Dynamics of ocean heat transport variability
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»Estimates of tidally-driven mixing
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»Oceanic eddy heat transport
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»Subtropical mode water during KESS
»North Atlantic Ocean circulation from GRACE
»Subtropical mode water in the Kuroshio Extension
»Tidal mixing during the Last Glacial Maximum
»Kuroshio northern recirculation gyre
»Bottom pressure in KESS and GRACE
»Ocean model metrics
»Abyssal mixing in CCSM
»Kuroshio Extension jet and transport
»The Morphology of Steve

B. Qiu, S. Chen, P. Hacker, N. G. Hogg, S. R. Jayne, and H. Sasaki , The Kuroshio Extension northern recirculation gyre: Profiling float measurements and forcing mechanism , Journal of Physical Oceanography, 2008

Mid-depth, time-mean circulation in the western North Pacific Ocean (28o-45oN, 140o-165oE) is investigated using drift information from the profiling floats deployed in the Kuroshio Extension System Study (KESS) and the International Argo programs.  A well-defined, cyclonic recirculation gyre (RG) is found to exist north of the Kuroshio Extension jet, confined zonally between the Japan Trench (~145oE) and the Shatsky Rise (~156oE), and bordered to the north by the Subarctic Boundary along ~40oN.  This northern RG, which is simulated favorably in the eddy-resolving OFES hindcast run model, has a maximum volume transport at 26.4 Sv across 159oE and its presence persists on the interannual and longer time scales.  An examination of the time-mean x-momentum balance from the OFES hindcast run output reveals that horizontal convergence of Reynolds stresses works to accelerate both the eastward-flowing Kuroshio Extension jet and a westward mean-flow north of the meandering jet. The fact that the northern RG is eddy-driven is further confirmed by examining the turbulent Sverdrup balance, in which convergent eddy potential vorticity fluxes are found to induce the cyclonic RG across the background potential vorticity gradient field. For the strength of the simulated northern RG, we find the eddy dissipation e ffect to be important as well.

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