Coastlines

• Discordant coastlines are bands of resistant and less resistant rocks that run at right angles to the coastline. This creates headlands and bays.
• Concordant coastlines are bands of resistant and less resistant rock that run parallel to the coastline. This creates coves.
• The 4 types of rock erosion are: attrition, abrasion, hydraulic action and solution.
• Headlands and bays form along a discordant coastline, over time the soft rock is eroded by waves being pushed against it, whereas the hard rock takes longer to erode as it is stronger. This causes the soft rock areas to erode away and leave dips in the coastline, known as bays. However the hard rock stays sticking out from the now receding soft rock, forming headlands.
• Coves are formed along concordant coastlines when a small crack forms in a band of hard rock. Over time this small crash is eroded through hydraulic action (air being pushed into it and forcing it to break away), it erodes to the exposed soft rock, where it erodes much faster causing a cove to be formed. However, the next band of hard rock prevents it from continuing to expand.
• Cliff retreat occurs when a large crack is opened up in the cliff by hydraulic action, the crack then grows into a cave by hydraulic action and abrasion and it gradually becomes bigger and bigger. The cave eventually erodes through the headland, forming a natural arch. The arch is eroded and collapses, leaving a tall pillar of rock, known as a stack. This is then eroded forming a shorter pillar known as a stump.
• Fetch is the distance of sea over which wind has travelled, the longer the fetch, the larger the waves. However, it is not to do with the strength ​of the wind.
• Wave size depends on the strength of the wind, how long the wind blows for and the fetch.
• Prevailing winds are the wind direction that blows the most often. The most common direction of wind in an area.
• Out at sea, the wind tugs at the surface of the water, causing the wave shape to move. Within a wave, each water particle moves in a circular motion and returns to its starting point. When a wave moves into shallow water near the coast, it is distorted until it 'breaks'. From this moment on, its not only the energy but also the water that moves forward. Water rushes up the beach - this is called the swash. And then it comes back down the beach - this is called the backwash.
• Constructive waves have a strong swash, more deposition, it builds up a beach, slow moving waves, longer time between each wave, and causes corrosion.
• Destructive waves have a strong backwash, are tall, occur in winter, have steep waves, are powerful, cause hydraulic action, cause attrition, cause abrasion and cause corrosion.
• A wave cut platform is formed when a cliff retreats due to the sea attacking the base of the cliff. The abrasion and hydraulic action form a wave out notch. The sea continues to attack the base of the cliff causing the top of the cliff to collapse and retreat.
• The main way sediment is transported is through longshore drift.
• Spits are formed when longshore drift carries sediment across a T-shaped section where a river meets the sea, depositing it in a long headland - like shape. However, the spit doesn't go all the way across as the river water comes down and carries the sediments away. A salt marsh forms behind the spit.
• A bar is formed when sediment is carried across a bay by longshore drift, depositing sediment across the bay and forming a lagoon.
• Swash is the movement of water up a beach.
• Infrastructure is organisational structures and facilities needed for the operation of a society or enterprise. Infrastructure is needed for a functioning society.
• Human uses of the coastline include: settlements, fishing, energy, agriculture, infrastructure and tourism.
• A direct impact is an impact caused by the proposed action and occurring at the same time and place.
• Indirect impacts on the environment are impacts that are not a direct result of the project but still as a result of it.
• Housing developments are allowing many people who work in London who can't afford housing there, to find good alternative housing opportunities. One direct impact of these developments is that lots of houses are having to be built. An indirect impact is that those who are commuting will contribute to the CO2 emissions.
• Office developments, companies are moving out of London due to the high prices, so they are moving to Bristol or Bournemouth. A direct impact of this is that there is land lost to buildings. An indirect impact of this is that the economy there improves and makes more money.
• Agriculture, the price of farmland has risen sharply and the need for extra grazing is putting pressure on wildlife habitats. A direct impact of this is that farmers cannot afford farmland. An indirect impact of this is that there is less produce.
• Industry, the essential developments bring conflict with tourists due to visual pollution. A direct impact of this is that there is less tourism to the coast, so the economy will suffer. An indirect impact of this is it deters tourists and tourism.
• The East coast of the UK is at the highest risk of flooding in 2150 as it is very flat ground. For example, Hull or Petersborough.
• Eustatic change effects the whole globe.
• Isostatic change only has a local impact.
• 10,000 years ago, the North of the UK was covered in ice, causing it to sink and the south to rise. However, after the ice age, when the ice melted, the North became much lighter. This has caused the South to slowly begin sinking and the North slowly begin rising, this is known as rebound.
• A coastline is at risk twice a day due to gravity of the moon, high tides cause sea level to rise; twice a month when there are exceptionally high tides called spring tides, this increases flood risk, especially if they coincide with large waves; and if air pressure falls very low, a storm surge occurs.
• Storm Ciaran is a key storm case study.
• Storm Ciaran caused 300 schools to close, 150000 homes to be left without power, rail services across the country to experience disruption and 16 people to die across Europe.
• Storm Ciaran caused damage to roads, bridges, railways and other infrastructure, many businesses were damaged by flooding and power outages, widespread damage to crops, a section of the West Bay cliff collapses following the large waves pounding the coastline that had been fuelled by the storm's strong winds and there was widespread flooding, which displaced wildlife and polluted water supplies.
• Storm Ciaran hit the South of England in 2022.
• The process shown below is known as longshore drift

  
• The below shoes a constructive wave

  
• The below shows a destructive wave

  
• The below shows the process of a wave cut platform formation.