Coasts and beaches

Abstract Coasts, often sedimentary in nature, serve as the dynamic interface between land and sea. While rocky shores exist along much of New England and the West Coast, the preponderance of United States coastal urbanization has occurred along sedimentary coasts. Indeed, much of the outer shoreline along the U.S. East and Gulf coasts is characterized by barrier systems. The study of sedimentary coasts is a multidiscipline effort involving geologists, physical geographers, and coastal engineers, including hydraulic engineers and fluid hydrodynamicists. These specialities can all be considered under the general field of coastal geomorphology wherein the morphological development of the coast, acting under the influence of winds, waves, currents, and sea-level changes, is the subject of these physical science investigations. Coastal engineering, while primarily a branch of civil engineering, leans heavily upon coastal and geological sciences. Their charge is to address both the natural and human-induced changes in the coastal zone, design structural and nonstructural devices and procedures to intercede against such changes, and evaluate the impacts of proposed solutions on these problem areas. Because numerous factors govern the development and evolution of coastal areas, solutions devised for one area will often fail if blindly applied to another. This stems from the wide-ranging morphologies and energy conditions found along the coast. Coastal engineering, therefore, is site specific, and project success requires careful collection and evaluation of all pertinent physical data from the geosciences. The coastal engineering literature is replete with coastal defense or harbor failures due to a lack of understanding of coastal processes. The importance of applied coastal research is clearly demonstrated by harbors built in Dublin, Ireland, during the nineteenth century.