what is a barrier island
Barrier islands. A barrier island is a long, thin, sandy stretch of land, oriented parallel to the mainland coast that protects the coast from the full force of powerful storm waves.Between the barrier island and the mainland is a calm, protected water body such as a lagoon or bay.Barrier islands are dynamic systems, constantly on the move, migrating under the influence of changing sea levels, storms, waves, tides, and longshore currents.arrier islands. A barrier island is a long, thin, sandy stretch of land, oriented parallel to the mainland coast that protects the coast from the full force of powerful storm waves.