Violent overturning events
and turbulence are produced in a
density-stratified fluid by numerous mechanisms including shear
instability, wave breaking and interaction of the flow with topography.
Mixing and energy dissipation occurs as a consequence. In the
stratified environments of the oceans and atmosphere, we are usually
interested in how much down-gradient density transport there is.
We are currently
quantifying the mixing in exchange flows past
constrictions and sills as a result of shear instabilities. These
processes are relevant to the flows in ocean straits, where the mixing
has important consequences for the transport of heat, salt and mass.