Key Idea:
The coast is shaped by weathering, mass movement, erosion, transportation and deposition.
Distinctive landforms result from different processes.
Coastal areas provide a unique environment and habitat.
There is a need for conservation and this leads to conflict with other land uses.
Specification Content:
Weathering processes – mechanical, chemical. Mass movement – sliding and slumping. Constructive and destructive waves.
Processes of erosion – hydraulic power, abrasion, attrition and solution. Processes of transportation – longshore drift, traction, saltation, suspension and solution. Deposition and the reasons for it.
Landforms resulting from erosion – characteristics and formation of headlands and bays, cliffs and wave cut platforms, caves, arches and stacks.
Landforms resulting from deposition – characteristics and formation of beaches, spits and bars.
Reasons for rising sea level. A case study to illustrate the economic, social, environmental and political impact of coastal flooding.
Rising sea level will have important consequences for people living in the coastal zone.
Coastal erosion can lead to cliff collapse.
This causes problems for people and the environment.
There is discussion about how the coast should be managed. There is debate about the costs and benefits of ‘hard’ and
‘soft’ engineering.
A case study of an area of recent or threatened cliff collapse – rates of coastal erosion; reasons why some areas are susceptible to undercutting by the sea and collapse; how people may worsen the situation; the impact on people’s lives and the environment.
Management strategies:
Hard engineering – sea walls, groynes, rock armour.
Soft engineering – beach nourishment, dune regeneration and marsh creation. Managed retreat. A case study of coastal management to assess the costs and benefits of strategies adopted.
A case study of a coastal habitat – its environmental characteristics; the resulting habitat and species that inhabit it and reasons why.
Strategies to ensure the environment is conserved, but also allow sustainable use of the area.

Key Words:
Key word:
Destructive waves
Fetch
Mass movement
Weathering
Erosion
Hydraulic action
Abrasion
Attrition
Solution (erosion)
Transportation
Definition:
Powerful wave with a weak swash and a strong backwash
The length of water over which the wind has blown
A mass of mobile vegetation, soil and rocks removes the surface covering further down the slope or cliff
This is the breakdown of rock at or near the surface. The three main types are:
 Mechanical- This leasdes to the breakdown of rock without any change in the minerals that form the rock, this varies with climate- eg
Freeze thaw action or exfoliation
 Chemical- This happens when the rocks mineral composition changes leading to it breaking up.
 Biological- this is caused by plants and animals- eg roots of trees weakening or widening joints/ cracks in the rocks
Wearing away the land surfaces, there are four main types.
The force of the moving water in the waves breaking down material
Waves erode the coastline by throwing pebbles against the cliff faces
Particles carried by the sea waves are reduced in size as they collide with one another and the cliff face
This is when a chemical reaction takes place between the seawater and the rock type causing the rock to break down
This is the movement of sediment
Example

Traction
Saltation
Suspension
Solution
Longshore Drift
Constructive waves
Swash
Backwash
Cliff
Wave cut notch
Wave cut platform
Cave
Arch
Stack
Stump
Deposition
Beach
Spit
Bar
Tombolo by the sea, there are four main types
Large boulders are rolled along the sea bed by waves
Smaller boulders are bounced along the sea bed
Sand grains are carried along in the water
Rocks completely dissolved in the water and are carried along
Lime from chalk.
Limestone.
The transport of sand and pebbles along the coast by waves
Gently breaking wave with a strong swash and a weak backwash
This is when waves break up the beach
This is when the water returns back the beach
A steep rock outcry along the coast Corton, Pakefield,
Dunwich
An undercut in the face of a cliff formed by the erosion of the waves
Gently sloping surface of rock in front of the cliffs exposed at low tide
Hollow at the bottom of a cliff eroded by waves
Rocky opening through a headland formed by wave erosion
Pillar of rock surrounded by sea, separated from the coast
A stack that has been eroded so that it falls into the sea
The process by which the sea drops the sediment that it is carrying
A gently sloping area of land between the high and low water marks
Ridge of sand or shingle attached to the land but ending in the open sea
Ridge of sand or shingle across the entrance of a bay or river mouth
A ridge of sand or shingle attached to the land but is also attached to

Threat of flooding
Hard engineering
Soft engineering
Managed retreat
Coastal management
Sea wall
Groyne
Conservation
Rock armour an island
Cause by rising sea levels and low lying coastal regions. controlled disruption of natural processes by using man-made structures
Using more long term sustainable techniques to manage flooding
Do nothing and allow the present coastline to change
This involves controlling development and change in the coastal zone
Concrete walls built to reflect the wave attack on the coast preventing erosion of the land behind
Wooden or steel piling. Concrete wall. Prevents longshore drift by trapping the materials/sediments.
To protect animals, fungi, plants and their habitats
Large boulders dumped on beach.
Very strong and protects coast from being eroded. Absorbs the energy and prevents undercutting by erosion and collapse.
Sea wall, coastal defences, rock armour, groynes
Beach nourishment, sand dune regeneration, marsh creation

Destructive waves
1.
They are high in proportion to their length
2.
The backwash is much stronger than the swash so that rocks, pebbles and sand are carried back out to sea (destroying or removing parts or all of some beaches [destructive])
3.
They are frequent waves, breaking an average of between
11 and 15 per minute
4.
More often seen during stormy conditions

Constructive waves
1.
They are long in relation to their height
2.
They break gently on the beach so that the stronger than the backwash (this means that more material is left than taken away)
3.
They break gently between 6 and 9 waves per minute

1. Wave erosion along a line of weakness produces a cut called a notch on the coast.
2. The notch is further eroded to form a cave, a hallow with an opening in a mass of rock.
3. Further erosion causes the overhanging part of the cave to collapse into the sea and a cliff is left behind.
4. Continuous erosion causes the cliff to move back or retreat inland. Over time, a wave-cut platform is formed at the foot of the cliff.
 Caves occur when waves force their way into cracks in the cliff face. The water contains sand and other materials that grind away at the rock until the cracks become a cave. Hydraulic
action is the predominant process.
 If the cave is formed in a headland, it may eventually break through to the other side forming an arch.
 The arch will gradually become bigger until it can no longer support the top of the arch.
When the arch collapses, it leaves the headland on one side and a stack (a tall column of rock) on the other.
 The stack will be attacked at the base in the same way that a wave-cut notch is formed. This weakens the structure and it will eventually collapse to form a stump.
 One of the best examples in Britain is Old
Harry Rocks, a stack found off a headland in the Isle of Purbeck.

Where the bay has been formed was softer rock. It has been eroded away from waves, hydraulic action, attrition abrasion and solution. The headlands that stick out are made of harder rock and so they don’t erode back.
As waves move towards headlands they focus maximum energy on the headland increasing erosion.
As waves move towards the beach they decrease in height as friction increases into the bay. Eroded material from the headlands is transported to the bays and trapped to form beaches.
BEACH
A beach is formed when deposited materials carried by waves are accumulated in a zone along the coast. The materials on the beach vary in size from fine sand to pebbles . The waves sort these materials according to the weight. The finer sand deposited nearer the sea and the coarser materials further inland.

Spit and Bar
Spits are created by the process of Long shore drift. Some eroded material ends up caught up within the waves and is carried by the sea along the coastline in cells known as littoral cells. Material is carried along the shore in a zigzag fashion by waves as they swash material up the beach at an angle and backwash material down the beach at a right angle. The angle of swash is determined by the prevailing wind
(the dominant or main direction in which the wind blows).
Wherever there is a break in the coastline (e.g. across a river or a change in coastline direction) then material is deposited closest to the shore. This is because there are often counter currents and a loss in velocity, so material is dropped or deposited.
Eventually this material builds up out into sea to form a spit. As seen in the picture opposite of Spurn Head. The spit often curves inwards towards the land as a result of the prevailing wind directing the waves which push the sediment in towards the shore.
If a spit extends from headland to headland then a bar will be created.

Human activity on the coast
1.
Recreation – Dog walking, holiday makers.
2.
Industry – ports, large ships with trade, tourism.
3.
Flooding – sea levels rise due to climate or storms. Bad for the houses/buildings/hotels etc.
4.
Pollution – Litter from tourists, dog mess on beaches and pollution from ships.
5.
Erosion – Cliff collapse and retreat threatening houses, tourists etc.
6.
Conservation – Beautiful landscapes and preserved. Protecting rare wildlife.

Sea Wall
Gabions
Usually done to…
Prevent erosion . (Might reach houses/building etc. dangerous. Loose tourism etc)
Preserve beaches that bring a lot of tourism etc.
The government carry out a cost-benefit analysis . This basically finds out if the coastal management scheme will be worthwhile . Will they get a substantial profit from it? Also they must realise how long the scheme will last and the environmental impacts of any work that is carried out (machines etc).
Soft Engineering Strategies
Prevent new building in coastal areas which are threatened by flooding or erosion . Often very vulnerable areas are red-lined so that any new building is forbidden .
Also they may choose to let nature take its course and encourage residents and businesses to relocate with the assistance of compensation packages . This way, little money is spent, natural processes are not being interfered with so there are no negative knock on effects. On the other hand many residents are reluctant to move because they have emotional memories from there. They may not have the money to move. People often argue to the council that the money to compensate is not enough and they are not being protected.
Hard Engineering Strategies
Concrete walls built to reflect the wave attack on the coast preventing erosion of the land behind.
Small Mesh cage filled with small rocks. They are able to move a little by are strong. They allow water in but absorb the energy of the wave and dissipate wave energy. Water can move inside to reduce risk of landslide and mudflows.
Armour Blocks
Large boulders dumped on beach. Very strong and protects coast from being eroded. Absorbs the energy and prevents undercutting by erosion and collapse.

Revetments
Open structure of planks to absorb wave energy allowing water through to build up sediment beyond. Revetments – These are sloping, slatted, timber walls set at about 45*. They are made from hard woods and the slats in them means water is partly reflected but partly dissipated + some of the water percolates between the slats. They stop undercutting and collapse of the cliff.
Groynes
Wooden or steel piling. Concrete wall. Prevents longshore drift by trapping the materials/sediments.

Cliff collapse and coastal management
Holderness east Yorkshire
No. one in Europe for coastal erosion.
In a stormy year waves remove
7-10 metres of land
29 villages have been lost to the sea in last 1000 years.
Farmland, caravan sites and holidays homes been lost to the sea
Rock type is Boulder clay which soft and not well cemented together
When it rains, water enters cracks and spaces in the rock.
Cliff tops become unstable and may slump into the sea.
When the wind blows from the
North or the North east waves have a long fetch so erode more.
50km’s of coastline endangered
Costs too much to protect all so certain areas are selected
MAPPLETON- small village under threat in 1990 however vital road B1242 passes through so needed protection
£2million send in 1991 on coastal protection scheme
Blocks of granite left at the bottom of the cliff
Two rock groynes to trap beach material
Beach will further protect the coast
CASE
Impact of coastal flooding
London and the Thames estuary
This includes central London which is vulnerable to flooding- happened in January 1953
Thames is focus of economic life in London- ‘City’ with banks, insurance companies, HQs as well as residential and historical properties. This includes Houses of parliament
If London flooded this could and would lead to a ‘financial disaster zone’ which impact on all the UK as well as the World
-
-
-
-
1.5 mill commuters work in region
Property is worth
£100m
69 tube stations, 400 schools and 16 hospitals
An lots of other infrastructure
Thames barrier was built between 1974-84 to protect.
Cost 0f £534 million
Barrier is raised 4-6 times a year
It is being raised more often due to sea levels rising
May need to be improved to deal with the new demands
CASE
STUDY
Coastal habitat and management
The Essex Marshes
Mixed landscape of mudflats, sand and shingle banks, salt marshes, coastal grasslands and sea walls.
CASE
Birds- oystercatcher
Plants- marsh samphire
STUDY
It is one of the top five coastal wetlands in Britain.
Habitat to:
Shore crabs and Herring Red,
Marshes under Threat
Over last 400yrs land has been reclaimed for farmland- sea walls were built
Only 2500 hectares out of
30000 hectares of marsh land still exists.
Human threats= urbanisation
Strategies for Conservation
Reversing 400 years of reclamation
Sea allowed to flood areas
Gaps made in existing sea walls
£12 million project will involve protecting arable land further inland. Otherwise land will be allowed to return to was before
Advantages for wildlife, creating flood buffer zone, and tourism
This is an example of managed retreat or sustainable development
STUDY