Beach profiles

• larger pebbles tend to be at the top of the beach and smaller pebbles tend to be at the bottom of the beach and are more rounded due to constant attrition and abrasion
• Seasonal changes create summer and winter profiles. Beach profiles are steeper in summer due to more constructive waves and less steep in winter due to more destructive waves
• spit?

  a long and narrow point of land that is made of sand and extends into sea

  sand is moved along the coast by longshore drift

  sediment begins to build up at the mouth of the river

  the end of the spit will also begin to curve round as wave refraction occurs
• Tombolo- a beach that has a small island in between island and mainland

  may be covered at high tide
• offshore bars?


  submerged ridges of sand or sediment created by waves offshore from the coast

  Destructive waves erode sand from the beach with their strong backwash

  act as both sediment sinks and stores due to the ability to absorb wave energy as well as reducing the impact of waves onto the coast
• Barrier beach?


  Where a beach or a spit extends across a bay to join two headlands

  believed to have been deposited following sea level rises

  longshore drift has added more material and has reworked the sediment

  a general term for any beach protecting the coast
• Sand dunes?


  large tidal range creating large exposure of sand to dry

  formed when sand is deposited by longshore drift is moved up by the wind

  vegetation helps to stabilize the sand
• Salt marsh?


  areas of flat silty sediments that accumulate over estuaries

  where salt and freshwater meet

  covered at high tide
• Sea level change?


  changes in climate-increase in temperature causes melting ice therefore higher sea levels

  decrease means more snow which increases volume of water stored in glaciers so less volume of sea
• What is eustatic change?

  when the sea level itself rises or falls
• what is isostatic change?

  when land rises or falls, relative to sea
• swash aligned beaches?


  in low energy environments eg bays

  waves arrive parallel to the coast
• Drift aligned beaches?


  waves approach at an angle which depends upon the prevailing winds

  can cause spit or bar due to longshore drift