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• How do waves form?

  Wind + water --> friction - affected by wind speed - increased wind means more friction and wind duration - how long it blows - faster wind and a long time means larger waves

  
• What is the fetch?

  the distance the wind travels over the water

  a longer fetch means more friction and waves pile up more meaning larger waves

  
• What are the different types of wave?

  Destructive and Constructive waves
• What are the characteristics of a destructive wave?

  - weak swash

  - strong backwash - removes sediment and erodes a beach

  - short wavelength

  - tall and plunge downwards

  
• What are the characteristics of a constructive wave?

  - strong swash - builds a beach up by depositing sediment

  - weak backwash

  - long wavelength

  - small and spills forward

  
• What are the weathering processes?

  - Mechanical

  - Chemical

  - Biological

  
• What happens at mechanical weathering?

  1. It rains during the day

  2. Rain fills up small cracks within rocks

  3. The water freezes overnight in the right climate

  4. Ice is formed and it expands

  5. Expanding rock cracks rocks wider

  6. Cracks get so wide that the rock fractures and breaks (freeze-thaw weathering)

  
• What happens at chemical weathering?

  1. Rainwater often contains small amounts of dissolved acid

  2. Small amounts of CO2 dissolve in droplets creating carbonic acid

  3. SO2 from volcanoes/coal power stations dissolves in water droplets in clouds

  4. Stronger acid called sulfuric acid is created

  5. Raindrops fall and hit rocks and dissolve the surface

  
• What happens at biological weathering?

  1. Rocks have weaknesses called joints within them

  2. They're formed by layers of sand and mud building up on ground over time

  3. After millions of years weight of sediment on top of itself presses that sediment together that it becomes rock

  4. Sedimentary rocks have cracks between layers

  5. A tree grows on surface of sedimentary rock and roots have space to pass through

  
• How do rock falls occur?

  1. Happens due to all 3 weathering processes

  2. Damage the rock enough that rock falls straight downwards

  
• How do mudslides occur?

  1. Impermeable rock is overlayed by a soft layer of soil

  2. When it rains, water is absorbed by soil and soil becomes heavy

  3. If soil is on a hill, soil becomes so heavy that it can no longer hold its own weight and slides down the hill
• How does slumping occur?


  1. Occurs when a whole area of coastline of land is made up of permeable rock or soil

  2. Whole coastal area fills up and saturates with water

  3. As there's no bedrock, whole region of hill collapses

  
• What are the different types of erosion?

  - Hydraulic Action

  - Abrasion

  - Attrition

  - Solution

  
• What happens at hydraulic action?

  1. Water enters cracks

  2. Air is compressed and pressure builds up

  3. This repeats

  4. The rock breaks off
• What happens at abrasion?


  Loose rocks rub/smash against the cliff
• What happens at solution?

  acid in the salt water dissolves the rock
• What happens at attrition?

  rocks smash into each other, makes them smaller and smoother
• What happens in deposition?

  Wave refraction

  1. Part of the wave touching the rock slows down due to friction

  2. Central part of wave continues - wave curves - the wave decelerates and spreads over the large area

  3. Deposition occurs - beaches formed
• How do headlands and bays form?

  1. Happens on a discordant coastline - alternating bonds of hard and soft rock perpendicular to the sea

  2. Differential erosion occurs - soft rock is eroded quicker, hard rock is eroded slower

  3. The hard rock protrudes (sticks out) as it is eroded slowly - headland is formed

  4. Soft rock erodes quicker and so it retreats - bay is formed

  
• How do wave cut platforms form?

  1. Exposed headlands or cliffs

  2. Base of cliff is eroded by waves from hydraulic action or abrasion

  3. continued erosion at base of cliff forms a wave cut notch

  4. wave cut notch deepens, cliff is unsupportive and it collapses

  5. Sediment is removed by waves - erosion continues - new wave cut notch formed

  6. process repeats, cliff retreats

  7. The flat rock area remains = wave cut platform

  
• How do coastal stacks form?

  1. Wave erodes weaker points in a headland

  2. Cracks get larger and form caves overtime, cave deepens and breaks through headland to form an arch

  3. Weathering weakens the roof of arch, it collapses and leaves an isolated stack behind

  4. The stack continues experiencing weathering and erosion and it collapses to form a stump
• How does longshore drift occur?

  1. Prevailing wind is at an angle to the coast

  2. As a result, waves approach at an angle, swash moves sediment diagonally up a beach

  3. Gravity - backwash pulls sediment straight down and the process repeats forever

  
• How do coastal spits and bars form?

  1. Longshore drift transports sediment along a coast

  2. Sediment reaches a bend in the coastline, this transports across the bay and deposits and builds up to form a spit

  3. Wave refraction and wind cause spit to curve - recurved end

  4. Sheltered area behind spit experiences deposition (mudflat) over time this builds up and plants grow as it's less salty (saltmarsh)

  5. The spit grows across bay and 2 headlands are connected - bar is formed - the lake behind is a lagoon
• How do beaches and sand dunes form?

  1. Wind blows onshore, obstacles like driftwood trap sand and sand builds up

  2. First embryo dune forms, small pioneer plants grow as their salt resistant. More sand is trapped and roots stabilise the dune

  3. The embryo dune grows and is blown inland (mobile dune) - a yellow dune is formed

  4. a new embryo dune forms behind - yellow dune moves inland - mature dune - trees
• What are the hard engineering strategies for coastal management?

  Rock Armour - large, dense boulders made of highly resistant rock

  Gabions - rocks in cages

  Groynes - wooden/rock barriers built perpendicular to the sea

  Sea wall - walls that reflect wave energy

  
• What are the advantages and disadvantages of rock armour?

  Advantages:

  
  

  1. Highly effective at protecting erosion - dissipates (absorbs) wave energy

  2. Environment - ecosystems can form between rocks

  
  

  Disadvantages:

  
  

  Cost - expensive - UK average is £5k per metre

  
• What are the advantages and disadvantages of gabions?

  Advantages:

  
  

  Prevent mass movement like slumping

  
  

  Disadvantages:

  
  

  1. Aesthetics - considered unattractive - unsuitable for tourist locations

  2. Expensive - £2k per metre

  
• What are the advantages and disadvantages of groynes?

  Advantages:

  
  

  1. Prevents longshore drift - allows a beach to build up

  2. Wider beach - more friction with waves - lower velocity - lower erosion

  3. Tourism - beaches are a key attraction

  
  

  Disadvantages:

  
  

  Terminal groyne syndrome - groynes prevent sediment reaching beaches down the coast - eroded - coast erodes faster

  
• What are the advantages and disadvantages of sea walls?

  Advantages:

  
  

  1. Durable - can last at least 20 years

  2. Can build and walk on top of them - useful for towns (e.g. Bournemouth)

  
  

  Disadvantages:

  
  

  Cost - £10k per metre

  
• What are the soft engineering strategies for coastal management?

  Sand dune regeneration - planting stabilising vegetation

  Dune fencing - protect dunes from human activity like tourism

  Beach nourishment - adding sediment to a beach - beach is widened - increased friction - less velocity - less erosion

  Managed retreat - controlled or managed advance of sea
• What are the advantages and disadvantages of sand dune regeneration?

  Advantages:

  
  

  Environment - habitats - Wales - has 50 bird species

  
  

  Disadvantages:

  
  

  1. Time - for vegetation to grow and sand to build up - not immediately effective

  2. Space - unsuitable for towns as there would be a lack of space - suitable for rural areas

  
• What are the advantages and disadvantages of dune fencing?

  Advantages:

  
  

  Increases the durability of dunes

  
  

  Disadvantages:

  
  

  Economic disadvantage - local businesses become losses due to reduced tourism

  
• What are the advantages and disadvantages of beach nourishment?

  Advantages:

  
  

  1. Leads to a wider beach meaning more tourists

  2. cheap - £500-2000

  
  

  Disadvantages:

  
  

  Maintenance - sediment needs to be added repeatedly so costs would continue increasing

  
• What are the advantages and disadvantages of managed retreat?

  Advantages:

  
  

  It's sustainable

  
  

  Disadvantages:

  
  

  Unfeasible on valuable areas of coast

  
• What are the main parts of a river?

  1. Watershed: outer perimeter in mountains of a river's drainage basin

  2. Drainage basin: the area of land around the river within which rain flows into the river

  3. Source: the start of a river - in mountains or hills

  4. Tributary: smaller river with the drainage basin that joins main river

  5. Confluence: meeting of tributary and main river

  6. Mouth: where the river meets the sea/ocean
• What is a river's long profile?

  This shows the change in gradient from source to mouth

  
  

  1. Upper course: gradient is very steep, river is narrow

  2. Middle course: gradient gets shallower, river is wider

  3. Lower course: gradient is almost flat, river is very wide

  
• What is a river's cross profile?

  This shows the change in shape of the river channel and the land around

  
  

  1. UC - river is narrow and shallow, V-shaped valley, vertical erosion

  2. MC - river is wider and deeper, U-shaped valley, lateral erosion

  3. LC - river is very wide and deep, valley is flat, deposition occurs

  
• What landforms occur in the upper course of a river?

  Interlocking spurs

  Waterfalls and gorges

  
• What landforms occur in the middle course of a river?

  Meanders

  Oxbow lakes

  
• What landforms occur in the lower course of a river?

  Floodplains

  Levees