WAVES, BEACHES AND THE SHORELINE
copyright Joseph Hull

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Waves
: wind-sculpted water surface, sinusoidal; the wave form moves, NOT the water

     waves (wind-made) vs tides (moon-made) vs deep ocean currents (sun-made)
     waves produced by wind-water interaction, drag on surface of water by wind
         unidirectional motion of wave form vs circular motion of water; waves at depth
     parts of the wave; wavelength, wave height (amplitude), wave velocity, shape
     earthquake-generated "tidal" waves or tsunamis; enormous wavelength, high velocity

Wave-Shore Interaction: waves change their shape and movement in shallow water
     shoaling of waves on bottom; changes in amplitude, wavelength, water motion
     breaking waves, surf zone, swash zone; energy expenditure; sediment abrasion
     oblique waves and longshore drift of water and sediment parallel to the shoreline
          special type of longshore current not produced by sun (see below)
     wave refraction (bending) and reflection (bouncing), wave interference

Rocky Shorelines (Erosional Beaches): northern Washington coast, e.g.
     rocky headlands and wave refraction (energy concentration); arches, seastacks
     wave cut platforms in solid rock; coastal uplift and formation of marine terraces

Sediment: beach sediment varies a lot depending upon energy, source materials, etc.
     production of beach sediment from rocky headlands; abrasion, water wedging, etc.
         other sediment sources: rivers, landslides onto beach, biogenic sediment
     sediment on beaches; cobble versus sand beaches, coral beaches, black sand, green sand

Longshore Drift/Transport of Sediment: very important process found on most shores
     oblique waves produce longshore transport of sediment; where's my beach blanket?
     transport rates and volumes: examples from the Washington coast
     associated landforms like sand spits, curved spits and hooks, baymouth bars, tombolos
     redistribution of sediment; case histories (Ocean Shores, Cape Shoalwater, etc.)

Depositional Beaches: sediment accumulating into large deposits.  Ocean Shores, e.g.
     parts of the beach; summer and winter berms, beach face, offshore bars
     changes in beaches from summer to winter; wave energy and sediment distribution
     barrier islands e.g. North and South Carolina, offshore sand bars
     mixed environments:  marine deltas, marine estuaries, lagoons, mangrove swamps

Beaches and Humans: beaches are NOT permanent, they are temporary, ephemeral
     Human interference: effects of jetties/groins, breakwaters, etc. on longshore transport
          case histories:  New Jersey shore, Santa Barbara, Santa Monica, Grays Harbor
     Shoreline armoring: retaining walls and bulkheads, effects on sediment and life
     Human habitation of beach environments: Washaway Beach, Point Chehalis
     Dams and sediment supply to beaches, beach erosion; clearcutting and sediment.
     Sea level changes and glaciation, emergent and drowned coastlines, fjords

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