Coastal morphodynamics is the study of interactions between coastal landforms and physical processes, such as waves, tides, currents, wind, sediment transport, and severe weather events. Shoreline evolution occurs over short- and long-term timescales through gradual and episodic changes influenced by interconnected factors, including hydrodynamic forcing, environmental conditions, and local geology. The field uses observations, practical and computer models to analyze the coastal environment and anticipate dynamic changes. Conclusions from coastal morphodynamics provide insight into the factors that shape coastlines and the effects of anthropogenic activity on coastal systems.
While hydrodynamic processes respond instantaneously to morphological change, morphological change requires the redistribution of sediment. As sediment takes a finite time to move, there is a lag in the morphological response to hydrodynamic forcing, making it a time-dependent coupling mechanism. Dissipative beaches are wide and flat in profile, with a wide shoaling and surf zone, composed of finer sediment, and characterized by spilling breakers.