Abstract
Transport and mixing processes during the geostrophic adjustment of a localized perturbation in the equatorial ocean are investigated numerically in the reduced gravity model. A finite volume scheme is designed which computes the advection of a (complex) tracer field together with the evolution of the dynamical variables. This method permits the study of transport processes.
The model supports the propagation of a finite amplitude Rossby waves with a closed recirculation region. The mass trapping occurs for solitary waves with relative amplitude greater than 0.3. Numerical simulations show that trapping can happen during the propagation of a small amplitude soliton on a sloping thermocline.
Transport during the process of geostrophic adjustment of localized perturbation is studied. An initial height or zonal velocity anomaly is split up into a fast zero group velocity gravity wave and a slow component which consists in a Kelvin wave and a Rossby wave. While Kelvin and gravity waves modify the tracer field through the Stokes drift only, the Rossby wave is transporting mass away from the initial perturbation westward.
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© 2005 Kluwer Academic Publishers
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Le Sommer, J., Zeitlin, V. (2005). Tracer Transport During the Geostrophic Adjustment in the Equatorial Ocean. In: Collet, P., Courbage, M., Métens, S., Neishtadt, A., Zaslavsky, G. (eds) Chaotic Dynamics and Transport in Classical and Quantum Systems. NATO Science Series, vol 182. Springer, Dordrecht. https://doi.org/10.1007/1-4020-2947-0_19
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DOI: https://doi.org/10.1007/1-4020-2947-0_19
Publisher Name: Springer, Dordrecht
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