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• Shoreline


  The line that marks the contact between land and sea
• Shore


  The area that extends between the lowest tide level and the highest elevation on land that is affected by storm waves
• Coast


  Extends inland from the shore as far as ocean-related features can be found
• Coastline


  The seaward edge of the coast
• Foreshore


  The area exposed when the tide is out (low tide) and submerged when the tide is in (high tide)
• Backshore


  Landward of the high-tide shoreline, usually dry, being affected by waves only during storms
• Nearshore zone


  Lies between the low-tide shoreline and the line where waves break at low tide
• Offshore zone


  Seaward of the nearshore zone
• Beach


  An accumulation of sediment found along the landward margin of the ocean or a lake
• Berm


  Relatively flat platforms often composed of sand that are adjacent to coastal dunes or cliffs and marked by a change in slope at the seaward edge
• Beach face


  The wet sloping surface that extends from the berm to the shoreline
• Beaches are composed of whatever material is locally abundant, such as eroded cliffs, sediment from rivers, or shell fragments and remains of coastal organisms
• Beaches can be thought of as material in transit along the shore, constantly being moved by crashing waves
• Wave crest


  The top of the wave
• Wave trough


  The bottom of the wave
• Wave height


  The vertical distance between trough and crest
• Wavelength


  The horizontal distance between successive crests (or troughs)
• Wave period


  The time it takes one full wave (one wavelength) to pass a fixed position
• Fetch


  The distance that the wind has traveled across the open water
• Waves can travel great distances across ocean basins, with the wave form advancing but the water itself not traveling the entire distance
• Circular orbital motion


  The movement of water particles in a circular pattern as a wave passes
• Observation of a floating object in waves reveals that it moves up and down, as well as slightly forward and backward, with each successive wave
• Wave erosion


  The process by which waves erode and shape shorelines
• During calm weather wave action is minimal. However, waves perform most of their work during storms.
• The impact of high, storm-induced waves against the shore can be awesome. Each breaking wave may hurl thousands of tons of water against the land, sometimes making the ground tremble.
• The pressures exerted by Atlantic waves in wintertime average nearly 10,000 kilograms per square meter (more than 2000 pounds per square foot). The force during storms is even greater.
• Abrasion


  The sawing and grinding action of water armed with rock fragments
• Abrasion is probably more intense in the surf zone than in any other environment.
• Smooth, rounded stones and pebbles along the shore are obvious reminders of the grinding action of rock against rock in the surf zone.
• Wave erosion occurs through wave impact and abrasion
• Sand movement on the beach


  The movement of sand along and perpendicular to the shoreline due to wave action
• Beach drift


  The zigzag movement of sand and pebbles along the beach face due to the oblique angle of wave swash and backwash
• Longshore currents


  Currents that flow parallel to the shore within the surf zone, transporting large quantities of sediment
• At Sandy Hook, New Jersey, the quantity of sand transported along the shore over a 48-year period averaged almost 750,000 tons annually. For a 10-year period at Oxnard, California, more than 1.5 million tons of sediment moved along the shore each year.
• Rip currents


  Concentrated movements of water that flow in the opposite direction from breaking waves
• Rip currents can be a hazard to swimmers, who, if caught in them, can be carried out away from shore. The best strategy for exiting a rip current is to swim parallel to the shore for a few tens of meters.
• Wave refraction


  The bending of waves as they approach the shore and encounter shallow water
• Wave refraction causes wave energy to be concentrated at headlands (resulting in erosion) and dispersed in bays (resulting in deposition).
• Over a long period, erosion of the headlands and deposition in the bays will straighten an irregular shoreline.
• Waves approaching the shoreline often bend