We investigate the velocity field and the three-dimensional flow paths obtained from a recently developed three-dimensional, nonlinear model that can simulate observed features of the Pacific Equatorial Undercurrent. The sensitivity of the flow field and the paths to the undercurrent are examined. The flow paths or trajectories used in the model were obtained from the exact solution of the velocity field. Nonlinear, three-dimensional features that can be simulated by the model include upwelling/downwelling, cellular flow structures, divergence of flow from the equator and extra-equatorial flows, a subsurface ocean “bridge” in the equatorial direction, and sharp changes in the gradient of the flow path.
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