Tue04Apr20174:00 pmLewis 101
Colloquium: Internal Wave Breaking and Boluses
Department of Mechanical and Industrial Engineering
Internal Wave Breaking and Boluses
The shoaling of internal waves on a continental slope results in wave steepening and breaking that produces boluses, which are trapped regions of fluid that travel up the slope with the wave. Unlike a propagating solitary wave, these boluses transport material with the wave containing oxygen depleted water and induce rapid changes in temperature both of which have potential ramifications for marine biology. The dramatic difference between the fluid inside the bolus relative to the exterior may also impact local acoustic measurements of the sea floor. We extend a number of two-layer studies by investigating bolus generation and material transport in continuously stratified fluids. Laboratory experiments are conducted in a 4 m long tank and are complemented by 2-dimensional numerical simulations. The boundaries of the bolus are identified using a Lagrangian based coherent structure method relying on trajectory clustering. We use the structure identification to measure the properties of the bolus as a function of the pycnocline thickness and slope angle.