Dynamics and Stability of Interacting Buoyant Currents
by Claudia Cenedese
Associate Scientist
Woods Hole Oceanographic Institution
Considerable
work is needed to improve our understanding of how buoyant waters
transport pollution and sediments along coastlines, in particular, when
multiple buoyant sources are present. A combination of analytical
calculations and laboratory experiments has been used to investigate
the interaction and stability of two surface-trapped buoyant coastal
currents having different densities. The possible horizontal and
vertical alignment scenarios are obtained by varying the densities and
volume transports of the two currents. These scenarios will be
presented as a function of dynamically relevant non-dimensional
numbers. Laboratory rotating experiments confirmed the analytical
prediction of the location of the two currents. Furthermore, the two
fronts were observed to go unstable. This coupled frontal instability
presents interesting differences from the previously studied
instability of a single current.