These findings emphasise the important role of a protective beach.
However, its effect can be limited depending on wave energy and the
volume of the beach (Robinson, 1977; Ferreira et al., 2000). This was
highlighted by the two-dimensional (2D) SCAPE model results of
Walkden and Dickson (2008),who found that the equilibrium recession
rate was insensitive to beach volumes below 30 m3/m. Similarly, the
field comparisons of the relationship between beach wedge area and
cliff recession rates made by Lee (2008) identified a threshold beach
volume of 20 m3/m.