ABSTRACT
This chapter illustrates some of the important roles that morphodynamic state play in modifying or controlling beach and surf-zone processes. It discusses the associations among morphodynamic state, surf-zone process signatures, modes of beach cut, and beach mobility based on field observations. Understanding the mechanisms and environmental conditions that cause short-term changes and favor different amplitudes of beach mobility is thus as important to coastal planning and defense as is understanding the causes of chronic beach recession. The chapter shows the field results obtained from contrasting environments around the coast of Australia. The authors’ field studies of different Australian beaches and surf zones encompass a wide range of temporarily and spatially varying environmental conditions, sediment types, and morphodynamic states. Depending on local environmental conditions, sediments, and antecedent wave conditions, beaches and surf zones may be dissipative, reflective, or in any of at least four intermediate states.
