Not subject to U.S. copyright. Published in 1997 by the American Meterological Society.

**Fig. 1. Mean meridional and S
sections in the top 500 m of the ocean from 10°S to 10°N along 165°E, 155°W, and
110°W. Contour intervals are 1°C (thick lines 5°C) for and
0.1 PSS-78 (thick lines 0.5 PSS-78) for S. Vertical exaggeration is
4000:1.**

**Fig. 2. As in Fig. 1 but for _{n}
and N^{2}. Contour intervals vary for both quantities, but thick lines
are at 1.0 kg m^{-3} intervals for _{n}
and 200 × 10^{-6} s^{-2} intervals for N^{2}.**

**Fig. 3. Salinity on _{n} = 26.5
kg m^{-3}, with contour intervals of 0.05 PSS-78 and saltier values
increasingly shaded (top panel). Depth of _{n} = 26.0
kg m^{-3}, with contour intervals of 25 m and deeper values increasingly
shaded (second panel from top). Depth of _{n} = 26.8
kg m^{-3}, with contour intervals of 25 m and deeper values increasingly
shaded (third panel from top). Thickness between _{n} = 26.0
and 26.8 kg m^{-3}, with contour intervals of 25 m and thicker values
increasingly shaded (bottom panel). All panels are objectively mapped from the values at
each mean hydrographic profile location as described in the text. The mapping uses the
Peters projection.**

**Fig. 4. Perspective view of the model jet from
30°W of south at 30° elevation (solid lines for visible jet boundaries, dashed lines for
hidden boundaries). The surface layer is not discussed. The pycnocline depth, D,
is the interface between layer 0 and layer 1. This interface is constant in latitude but
slopes linearly up to the east (upper plane of dotted lines). Since layer 0 is ignored, D
can be thought of as inverted topography at the top of layer 1. The interface depth
between the active layer 1 and the quiescent abyssal layer 2 is . This
deeper interface is constant on either side of the jet (lower sets of dotted lines), but
slopes up within it, where the velocity, u, is finite. The interface depths D
and are both negative values referenced to the surface, but their
difference, the layer 1 thickness, h, is a positive quantity. The reduced
gravity, g', at is related to the neutral density anomalies, _{n},
as discussed in section 5. As the pycnocline shoals to the east, the jet edges y_{e}
and y_{p} shift poleward as the jet thickens, conserving Bernoulli
function and potential vorticity on streamlines. Vertical-meridional exaggeration is
167,000:1 and meridional-zonal exaggeration is 124:1.**

**Fig. 5. Active layer thickness within the model jet
plotted against latitude from 140°E to 80°W at 20° intervals (top left panel) and
velocity plotted against latitude from 140°E to 80°W at 20° intervals (top right
panel). Jet edges (thick dashed lines in bottom panel) are plotted over thickness between _{n} = 26.0
and 26.8 kg m^{-3} as in the bottom panel of Fig. 3. The jet shifts poleward,
narrows in the meridional, thickens in the vertical, and accelerates to the east as a
consequence of conservation of potential vorticity and Bernoulli function under the
shoaling pycnocline.**

** **

**Table 1.** Geostrophic volume transport and
velocity calculations made for the Pacific SSCCs using the mean meridional sections at
each longitude, referenced to 700-dbar pressure. Only eastward flow between * _{n}* = 25.5
and 27.3 kg m

Transport calculations | Peak velocities | |||||

Section (long) |
Latitude bounds |
Volume Transport (10 ^{6 }m^{3} s^{-1}) |
Transport weighted (kg m_{n}^{-3}) |
Peak latitude |
Peak depth (m) |
Peak magnitude (m s ^{-1}) |

South SSCC | ||||||

165°E | 5°-2°S | 6.6 | 26.62 | 2.5°S | 250 | 0.17 |

155°W | 8°-3°S | 4.1 | 26.67 | 3.5°S | 250 | 0.07 |

110°W | 6°-3°S | 6.2 | 26.57 | 5.5°S | 160 | 0.16 |

North SSCC | ||||||

165°E | 2°-5°N | 10.3 | 26.58 | 2.5°N | 240 | 0.26 |

155°W | 2°-5°N | 7.0 | 26.63 | 3.5°N | 220 | 0.21 |

110°W | 3°-6°N | 7.4 | 26.45 | 4.5°N | 130 | 0.21 |

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