The sequencing, or chronology, of wave events plays an important role
in determining how coastlines and nearshore regions evolve over medium
and long timescales (from weeks to decades). However, present-day com
puter models of coastal morphology treat the input wave conditions in
either a deterministic (i.e. a single wave sequence) or a probabilisti
c manner. In neither method are the effects of the full range of possi
ble future wave sequences, for given overall statistical values, calcu
lated. The methodology presented here addresses this problem by multip
le model runs using different re-orderings of a wave sequence. A serie
s of tests demonstrate different aspects of wave chronology and its im
portance in the prediction of seabed and beach levels. The method prov
ides a means both for understanding wave chronology effects and for pr
edicting these effects in practical engineering problems involving med
ium and long timescale changes to coastal morphology.