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Title: Isopycnal Eddy Diffusivities and Critical Layers in the Kuroshio Extension from an Eddying Ocean Model

Journal Article · · Journal of Physical Oceanography
 [1];  [1];  [1];  [2]
  1. Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography
  2. Univ. of Hamburg (Germany)
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High spatial resolution isopycnal diffusivities are estimated in the Kuroshio Extension (KE) region (28°–40°N, 120°–190°E) from a global 1/10° Parallel Ocean Program (POP) simulation. The numerical float tracks are binned using a clustering approach. The number of tracks in each bin is thus roughly the same leading to diffusivity estimates that converge better than those in bins defined by a regular geographic grid. Cross-stream diffusivities are elevated in the southern recirculation gyre region, near topographic obstacles and downstream in the KE jet, where the flow has weakened. Along-stream diffusivities, which are much larger than cross-stream diffusivities, correlate well with the magnitudes of eddy velocity. The KE jet suppresses cross-stream mixing only in some longitude ranges. This study estimates the critical layer depth both from linear local baroclinic instability analysis and from eddy phase speeds in the POP model using the Radon transform. The latter is a better predictor of large mixing length in the cross-stream direction. Critical layer theory is most applicable in the intense jet regions away from topography.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography
Sponsoring Organization:
USDOE Office of Science (SC)
OSTI ID:
1565243
Journal Information:
Journal of Physical Oceanography, Vol. 44, Issue 8; ISSN 0022-3670
Publisher:
American Meteorological SocietyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 27 works
Citation information provided by
Web of Science

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Cited By (1)

Investigating Subsurface Pathways of Fukushima Cesium in the Northwest Pacific journal June 2019

Figures / Tables (14)

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FIG. 2(p. 4)figure FIG. 2
FIG. 3(p. 6)figure FIG. 3
FIG. 4(p. 7)figure FIG. 4
TABLE 1(p. 7)table TABLE 1
FIG. 5(p. 8)figure FIG. 5
FIG. 6(p. 9)figure FIG. 6
FIG. 7(p. 11)figure FIG. 7
FIG. 8(p. 11)figure FIG. 8
FIG. 9(p. 13)figure FIG. 9
FIG. 10(p. 14)figure FIG. 10
FIG. 11(p. 15)figure FIG. 11
FIG. 12(p. 16)figure FIG. 12
FIG. A1(p. 18)figure FIG. A1

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