1. Stately Spanish galleon coming from the Isthmus,

2. Dipping through the Tropics by the palm-green shores

3. John Masefield

Introduction

The coast is where geomorphic processes operate in combination. Waves and currents of the sea play the dominant role but coastal forms are also shaped by fluvial processes, mass movements and wind action. For example, the face of a coastal cliff is denuded by weathering, rainwash, rill action and mass movements, while the sea erodes its base (Fig. 10.1). Sediment derived from a coastal cliff is transported along the coast, as is sediment brought down by rivers flowing into the sea and material moved landwards by waves from the sea floor. The term 'coastal processes' includes all activities that take place at or near the sea. Coastal processes, however, are restricted to a narrow vertical range primarily determined by the sea level, and confined within the extreme tidal limits. The reach of the sea, however, extends in huge storms, e.g. tropical cyclones, or gigantic waves generated by tsunamis, but these are low-frequency events.