Breaking Waves on a Macrotidal Barred Beach: A Test of McCowan's Criteria

Abstract

The location of the breakpoint on a macrotidal beach can vary in a discontinuous manner due to the presence of longshore bars. A number of studies have examined controls on the water depth at which breaking occurs. Here we extend those analyses to test predictions of the location of the breakpoint on a barred profile. Observations of breakpoint position and corresponding wave parameters are reported from Gibralter Point on the North Sea coast of eastern England. The results continue to support the theoretical analysis of McCowan (1894) and suggest that a value of 0.78 for the ratio of the wave height to the water depth at the breakpoint can be used to model breaker location to + / - 5 m on a 300 m wide intertidal profile.