Transport by coherent barotropic vortices

This article reviews the transport properties of coherent vortices in rotat ing barotropic flows. It is shown that vortices induce regular Lagrangian m otion inside their cores and are highly impermeable to inward and outward p article fluxes. Passive tracers can be trapped inside vortex cores for long times and are transported by the vortex motion over large distances. Absol ute dispersion in vortex-dominated flows is discussed by studying particle dynamics in 2D turbulence, point-vortex systems, and subsurface float traje ctories in the ocean. Finally, it is shown that anticyclonic coherent vorti ces in cyclonically rotating reference frames can concentrate heavy impurit ies (e.g. dust grains) in their cores. This process may play an important r ole in the formation of planetesimals in the early solar nebula.