American Meteorological Society, Journal of Physical Oceanography, 7(24), p. 1666-1679, 1994
DOI: 10.1175/1520-0485(1994)024<1666:dooteb>2.0.co;2
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The wind-driven transport and velocity structure are estimated from direct current measurements and geostrophic shears along a transpacific section at 10°N. The total velocity field is dominated by the North Equatorial Current and its eddies, while the shear features near-inertial oscillations and a wind-driven current spiral. The section-averaged cross-track ageostrophic shear can be approximated as a slab layer 30-40 m thick with a velocity of 0.05 m s-1 overlying a sheared layer in which the velocity goes to zero below 80 m. The resulting zonally integrated ageostrophic mass transport is 62 (±10) × 109 kg s-1 northward, similar to the estimate of 52 (±10) × 109 kg s-1 predicted by the Ekman balance using winds measured from the ship. Climatological winds yield similar transports. The zonally averaged velocity relative to the top of the thermocline forms a clockwise spiral, decaying with depth. As has been found at higher latitudes, this mean wind-driven spiral results from the diurnal cycling of the mixed layer depth. -Authors