Numerical models of transport and mixing have to date been exclusively kinematic, i.e., where a periodic velocity field is imposed. The strongest criticism of these models is the inherent dynamical inconsistency that these flows, unlike exact solutions of the inviscid equations of motion, do not conserve potential vorticity. We examine a kinematic model of two Rossby waves moving down a channel, and contrast it with a comparable dynamically consistent model. The aim of this comparison is to identify which structures of transport and mixing seen in the kinematic models are found in the dynamical models, and which are not. We examine the flow using return maps, finite time Lyapunov exponents, effective diffusivities, and particle fluxes. Particular attention is paid to barriers to transport in the flow, their leakiness and (for certain parameters) their destruction.
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12th Conference on Atmospheric and Oceanic Fluid Dynamics