252
7 Ocean Currents
force for horizontal circulation in the nearshore zone is provided by spatial gradients of the excess momentum flux. Cross-shore gradients are largely balanced
by pressure forces that result in the set-up of the mean water level.
Generally, the requirement of mass conservation leads to nearshore cells of
horizontal circulation. For a wave field with a small, spatially periodic, longshore variation in wave height, longshore currents are generated within the
surf zone from each longshore maximum, to longshore minimum, of the wave
height. Associated rip currents are usually located at each wave height minimum. A detailed description of modelling nearshore circulation is given by
Massel (1989) and Battjes et al. (1990).
7 Ocean Currents
force for horizontal circulation in the nearshore zone is provided by spatial gradients of the excess momentum flux. Cross-shore gradients are largely balanced
by pressure forces that result in the set-up of the mean water level.
Generally, the requirement of mass conservation leads to nearshore cells of
horizontal circulation. For a wave field with a small, spatially periodic, longshore variation in wave height, longshore currents are generated within the
surf zone from each longshore maximum, to longshore minimum, of the wave
height. Associated rip currents are usually located at each wave height minimum. A detailed description of modelling nearshore circulation is given by
Massel (1989) and Battjes et al. (1990).