Stratification effects on shoaling internal solitary waves

This combined numerical/laboratory study investigates the effect of stratification form on shoaling characteristics internal solitary waves propagating over a smooth, linear topographic slope. Three types are investigated, namely (i) thin tanh (homogeneous upper and lower layers separated by pycnocline), (ii) surface (linearly stratified layer overlaying homogeneous layer) (iii) broad (continuous density gradient throughout water column). It is found that affects breaking type associated with wave. In stratification, good agreement seen past studies. Waves shallowest slopes undergo fission. Over steeper slopes, changes from surging, through collapsing to plunging increasing wave steepness $A_w/L_w$ for given slope, where $A_w$ $L_w$ incident amplitude wavelength, respectively. regime, classification differs stratification. Plunging dynamics inhibited layer, instead collapsing-type breakers equivalent location in parameter space profile likewise near-bottom prevents dynamics. Instead, all either fission or surging breakers. As increases, bolus formed exhibits evidence Kelvin–Helmholtz instabilities its boundary. both two- three-dimensional simulations, billow size grows steepness, not previously observed literature.