The simulations have demonstrated how shore profile shape and
cliff recession rate respond to the outcropping of a rock layer of different
resistance. The finding that weaker (/more resistant) layers lead to
more (/less) rapid retreat is intuitive, given the description of the erosion
rate presented in Eq. (1). More surprising is the asymmetry of the
response of the cliff erosion rate to changes in layer resistance, and
the difference in the timeframe of the response. This is highlighted by
Fig. 13, which shows the retreat rates as a proportion of that for a homogenous
cliff versus the relative strength (Eq. (3)) of anomalous layers
situated at −6 to −1 m relative to MSL