The Erosion of Long Island's Barrier Beaches The barrier beaches, which line the south shore of Long Island are in a constant state of change due to factor's such as wind, tides and wave action. "The term 'barrier' identifies one that protects other features, such as lagoons, salt marshes, and bays from direct attack from the open ocean" (Leatherman 1). The pebbles and sand of which these beaches are made constantly lifted and deposited in other areas. Currents created by tides and waves carry sediment and deposit it on beaches and in shallow water areas along the shoreline. In this paper I will discuss wave activity, the most prevalent factor of beach erosion. In addition, I will examine the roll of sand dunes and other ways of preventing erosion. The problem which many Long Island beaches face today is the element of erosion. More sediment is carried away from the shoreline than is deposited. These elements of nature make the barrier beaches very unstable features of Long Island's south shore. Wave action, tides, and winds constantly change beaches and shorelines, and are the cause of the many devastating effects of erosion. The barrier beach which I have chosen to focus my research on is TOBAY beach, a beach located just east of Jones Beach. Like TOBAY, barrier beaches are usually the result of a sandbar which is built up and develops as an islands. They are continuously gaining and losing sand, and slowly move landward. This is known as barrier island migration. "Sand from the ocean side of the barrier is transported by water and wind toward the backside of the island so that the whole landform gradually changes its location" (Leatherman 47). The constant movement of sediment from the front of the beach to the back is known as rollover. IF the barrier beaches did not move, they would eventually be covered by water. In a way, barrier island migration acts against the effects of erosion.