Internal Solitary Waves in Shallow Seas and Lakes

We give a brief account of the basic theory of internal solitary waves with the emphasis on applications to observations in shallow seas and lakes. Starting with the equations of motion for an inviscid incompressible fluid, we indicate how various asymptotic models for weakly nonlinear long waves are derived, including the well-known Korteweg-de Vries equation. We then describe the solitary wave solutions, and relate their properties to observations. Various generalisations are considered taking into account effects such as friction, variable bottom topography, and wave refraction.