Internal solitary waves (ISWs) are finite amplitude waves of permanent form that travel along density interfaces in stably stratified fluids. They owe their existence to an exact balance between non-linear wave steepening effects and linear wave dispersion. They are common in all stratified flows especially coastal seas, straits, fjords and the atmospheric boundary layer. In the ocean, they are a source of momentum and mixing that can (i) transport heat and nutrients vertically, (ii) re-suspend sedimentary material and (iii) transport mass over large distances. They are subsequently of interest from both an environmental and offshore engineering point of view.

Numerical (contour advective pseudo-spectral) and experimental (sluice gate) techniques to model large amplitude ISWs will be presented. In particular investigation of (i) shear-induced instabilities in large amplitude ISWs, (ii) near bottom instabilities in the wave induced bottom boundary layer, (iii) mode-2 wave characteristics and (iv) interaction of ISWs with sea-ice will be explored.