A distinguishing characteristic of ocean dynamics in shallow coastal and shelf
regions is the interaction that exists between seabed conditions and the overlying
layers of water. The interaction takes place because of the strong influence of seabed
topography and friction on the form of the shallow-water dynamics. The interaction
is two-way because of the dynamically induced alterations in the seabed topography
that result from sediment movement. In turn, these alterations lead to changes in the
near-seabed currents and the frictional processes themselves. The scales involved
range from those of high-frequency surface gravity wave propagation over beaches
up to those of tidal- and wind-induced circulations in shallow shelf seas.
