Monday, August 20, 2007

Coasts Revision

Revising the Coasts Unit:
We have now come to the end of the Coasts Unit and its time to revise!
Here are some resources to help you.

Check list of key concepts to revise:

1. Energy at the coast - types of waves and basic principles behind wave formation / factors affecting the strength of waves

2. Coastal Processes - erosion processes (you need to be able to describe the processes and how they work); transport processes (you must be able to talk through the process of longshore drift and it helps if you are able to draw an annotated diagram to show the process) and deposition

3. Coastal Erosion Landforms - you must be able to talk through both the features and formation of the following landforms: cliffs; wave-cut platforms; headlands and bays; caves, arches, stacks and stumps (in your description and explanation of formation always include some examples of named erosion processes that may be at work). You should also be able to draw annotated diagrams of the features to show how they form as well as knowing named examples of each.

4. Coastal Deposition Landforms - you must be able to talk through both the features and formation of the following landforms: beaches; spits; bars and tombolos. You should be able to draw annotated diagrams of the features to show how they form as well as knowing named examples of each.

5. Case Study of Coastal Erosion - learn (including detail - i.e. location, facts and figures) a case study of coastal erosion - either Dunwich or the Holderness Coast.

6. Coastal Defence - you need to be aware of the options for coastal defence - hard engineering, soft engineering or managed retreat. You should be able to describe coastal management techniques and be able to discuss their advantages and disadvantages. You should learn a named case study to back this up - for example either Aldeburgh or Overstrand.

Revision Resources:
- make good use of your class notes
- make use of blog posts to consolidate your understanding / recap concepts you are less sure of (to access previous posts - use blog archive list on the left hand side of the blog - August posts) - remember there are various links to animations etc. to help you.

Interactive Revision Quizzes:
You must learn your notes (particularly case study detail) but once you have revised from your notes there are some interactive revision quizzes etc. here for you to test yourself.
Coast Key Word Flash Cards (definitions then key words)
Coasts Key Word Flash Cards (key words then definitions)
Coasts Key Word Test
Coastal Features Recognition and Examples Test
Coastal Management Quiz
Coasts Revision Quiz 1
Coasts Revision Quiz 2 - Penalty Shootout
Coasts Revision (Walk the Plank) - Hull Trinity School
Coasts Questions - Practice Paper
Coasts Downloadable Flashcards
Coasts Revision Dominoes
Coastal Features Countdown Conundrum
Crazy Coasts (Half a min - anagrams)
Coasts Dustbin Game - sorting erosion and deposition features
Coasts Dustbin Game - Erosion and Deposition Features Case Studies

Coasts Podcasts
Podcast 1 - Energy at the Coast - waves and wave formation
Podcast 2 - Coastal Processes
Podcast 3 - Coastal Erosion Features
Podcast 4 - Coastal Deposition Features
Podcast 5 - A case study of coastal erosion - Dunwich
Podcast 6 - Coastal Defence

Coastal Defence

When managing the coastline there are two main options:
- this is where man made coastal defence structures are used to reflect large amounts of wave energy and hence protect the coastline.
- this is where beaches or naturally formed materials are used to control / re-direct erosion processes.

You need to know examples of coastal management techniques and their advantages and disadvantages:

Hard Engineering Techniques:

1. Re-Curved Sea Wall
- concrete wall which is curved on the underside to deflect the power of the waves
- these can be very expensive (up to £1-2 million per km) and the deflected waves can scour material at the base of the wall causing them to become undermined
- these are however a very effective means of preventing erosion and they reflect rather than absorb wave energy.

2. Rip Rap
- large boulders on the beach absorb wave energy and break the power of the waves
- although movement of the boulders is expensive this can be a much cheaper method than some other solutions
- the boulders can however be undermined easily by waves washing away sand and shingle beneath them. They also can be quite ugly, changing the appearance of a coastline.

3. Groynes
- these structures (usually either wooden or steel) are designed to top longshore drift and therefore act to build up and anchor beach material, protecting the base of cliffs.
- they are effective at reducing erosion in the area they are constructed in by causing significant build up of beach material
- groynes may however starve areas further down the coast of material by stopping longshore drift, resulting in an increase in erosion in these areas

4. Gabions
- these cages of boulders are built into cliff faces to protect the cliff from the force of the waves;
- they are cheaper than sea walls and can be very effective where severe erosion is a problem
- they are however visually intrusive

5. Revetments - these wooden structures break the force of waves and beach material builds up behind them
- they are cheap and effective at breaking waves
- as well as being visually intrusive however they do need replacing more frequently than most other defence methods.

Soft Engineering Techniques

Soft engineering includes beach replenishment in which beach material is added to provide a "natural solution". Environmentally this is a preferred option as it maintains the beauty of the landscape and avoids visual intrusion, however it can be expensive to maintain as longshore drift continues to move beach material down the coast and therefore regular replenishment is required.

Sand Dunes and salt marshes can also be encouraged to act as natural barriers to the waves.

Case Study of Coastal Defence: Aldeburgh (Suffolk)

Aldeburgh is just south of Dunwich, here a large scale coastal defence scheme is in place to control erosion. Aldeburgh is a busy town and tourism is very important to the local economy in this area. It is therefore seen as cost effective to have a coastal defence scheme in place to protect the economically valuable land.

Hard engineering is in place with a combination of sea wall, rip rap and groynes. There is also an area of salt marsh to absorb some of the waves energy should it breach the sea wall.

Another area severely affected by coastal erosion and where significant coastal defences are in place is Overstrand on the North Norfolk Coast, pictures of the coastal defences in this location can be seen here.

Further north, the small village of Dunwich is also severely affected by coastal erosion, yet very little, apart from some small soft defences and a recent limited and unsuccessful attempt at hard engineering is in place - here is a very useful account of the reasons for the differences in the extent of coastal defence between Dunwich and Aldeburgh.

Wooden Revetments and Gabions:

Follow up links:
Download a Coastal Defences summary sheet (includes advantages and disadvantages)
Coastal Management (BBC Bitesize)
Coastal Management Strategies (S-Cool) - very good!

Podcast: Coastal Defences
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Case Study of Coastal Erosion - Dunwich (Suffolk)

The Suffolk coastline of East Anglia has been eroding for 1000s of years and suffers rapid and frequent change - the changes are due to the coastal processes of erosion and deposition and the large scale movement of material down the coast by longshore drift.

Dunwich is a very small village located on the east coast in Suffolk. Dunwich was once a thriving port, similar in size to London, but storms, erosion and floods have almost wiped out this once prosperous settlement, which once had a population of 4,000 as well as a flourishing port. All that remains now are a few cottages - yet at one time there were 6 churches and 3 chapels. Most of old Dunwich now lies on the sea floor.

It is predicted that with our changing climate, storm events will become more frequent and in 1990, 7 metres of the coastline was lost over a few days in a storm that hit the Dunwich Coast.

So why is Dunwich so affected by coastal erosion?
- the coastline at Dunwich is made up of soft rock (sands, gravels and clays), these are easily eroded by the sea;
- the problem is made worse by the narrow beach which results in wave attack at the base of the cliff;
- the cliff faces are also greatly affected by weathering processes;

Rates of erosion at Dunwich are now as great as one metre per year. Material that is eroded from the Dunwich cliff line is moved down the coast by the process of longshore drift, keeping the beach fairly narrow. The material is transported in a N-S movement where it is deposited further south to form Orfed Ness Spit.

Although prone to severe coastal erosion, Dunwich has relatively little sea defence. An area of marshland just beyond the car park has been protected from the sea by a long shingle sea wall, but this has to be regularly rebuilt by bulldozers. Until recently there has been no other coastal management and the natural creation of a new beach to absorb wave energy has been seen as the most effective solution, due to the small size of Dunwich it has not be seen as cost effective to spend millions on sea defence at this location. However in February 2007, a new experimental beach stabilisation project began, it has been designed to try and reduce the severe cliff failures. A series of sand and shingle humps are to be created to stop the beach eroding and therefore help to reduce cliff erosion.

Another good example of coastal erosion is the Holderness Coast (Humberside)

Follow up links:
The Geology of Dunwich
Dunwich Photographs (Thanks to A Stacey "The Geography Department")
Low tide reveals lost city (BBC Article)
Work to shore up Beach to start (BBC Article)
Disappearing Village - sea claims another piece of Dunwich (Guardian Article from 1999)

Podcast: Case Study of Coastal Erosion - Dunwich
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Coastal Deposition Landforms: Features and Formation

Material that is transported by the waves along a coastline is eventually deposited forming distinctive deposition features. There are four main deposition features that you need to learn the formation of. These are:

1. Beaches
2. Spits
3. Bars
4. Tombolos

Beaches Beaches are the main feature of deposition found at the coast, these consist of all the material (sand, shingle etc.) that has built up between the high and low tide mark. There are number of different sources of beach material - the main source being rivers, where fine muds and gravels are deposited at the river mouth. Other sources of beach material include longshore drift (bringing material from elsewhere along the coast); constructive waves (bringing material up the beach from the sea) and from cliff erosion.

As constructive waves build up beaches, they often form ridges in the beach known as berms. The berm highest up the beach represents the extent to which the water has reached during high tide.

Click on the diagram below to see the main sources of beach material

Spits are long narrow ridges of sand and shingle which project from the coastline into the sea.

The formation of a spit begins due to a change in the direction of a coastline - the main source of material building up a spit is from longshore drift which brings material from further down the coast.

Where there is a break in the coastline and a slight drop in energy, longshore drift will deposit material at a faster rate than it can be removed and gradually a ridge is built up, projecting outwards into the sea - this continues to grow by the process of longshore drift and the deposition of material.

A change in prevailing wind direction often causes the end of spits to become hooked (also known as a recurved lateral).
On the spit itself, sand dunes often form and vegetation colonises (for example Blakeney Point - North Norfolk)
Water is trapped behind the spit, creating a low energy zone, as the water begins to stagnate, mud and marshland begins to develop behind the spit;
Spits may continue to grow until deposition can no longer occur, for example due to increased depth, or the spit begins to cross the mouth of a river and the water removes the material faster than it can deposited - preventing further build up.

Examples of Spits
- Spurn Head - Holderness Coast
- Orford Ness - Suffolk

Click below for an annotated diagram of spit formation:


These form in the same way as a spit initially but bars are created where a spit grows across a bay, joining two headlands. Behind the bar, a lagoon is created, where water has been trapped and the lagoon may gradually be infilled as a salt marsh develops due to it being a low energy zone, which encourages deposition.

Example of a Bar: Slapton Sands - Devon.


Tombolos are formed where a spit continues to grow outwards joining land to an offshore island.

Example of a Tombolo: - Chesil Beach - which joins the South Dorset coast to the Isle of Portland.


Remember - as well as being able to describe the formation of each feature of coastal deposition, you should be able to give a named and located example e.g. a spit - Spurn Head (Holderness Coast). You should also try and learn a labelled diagram to show the formation of each feature.

- Beach - Dawlish Warren (Devon)
- Spit - Orford Ness (Suffolk) or Spurn Head (Holderness Coast)
- Bar - Slapton Sands (Devon)
- Tombolo - Chesil Beach (joining S Dorset Coast to Isle of Portland)

Having now learnt both erosion and deposition features you need to make sure that you can distinguish between them. Have a go at the dustbin game below - click on play to begin. Start by studying the two lists when you think you are ready to test yourself on whether a landform is a feature of erosion or deposition start the game by clicking proceed. Drag the feature to the correct dustbin to make your choice!

click here for full screen version

Follow Up Links:
Animation of spit formation (Wycombe High School Link)
Bar and Spit Animation (Wycombe High School Link)
Longshore Drift Animation
Simple Longshore Drift Animation

Key Terms Check
Spit - a ridge of sand and shingle projecting from the mainland into the sea
Bar - a ridge of sand and shingle which has joined two headlands, cutting off a bay
Tombolo - a ridge of s
and and shingle joining the mainland to an island

Podcast: Coastal Deposition Features
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Coastal Erosion Landforms - Features and Formation

Coastal Erosion Features

There are 3 main groups of coastal features which result from coastal erosion:
1. Headlands and Bays
2. Caves, Arches, Stacks and Sumps
3. Cliffs and Wave-cut platforms

Before you revise the formation of these landforms, have a look at this video and make sure you are able to identify the landforms from their distinctive features.


Headlands are resistant outcrops of rock sticking out into the sea, whilst bays are indents in the coastline between two headlands.

So how do headlands form?

- Headlands form along discordant coastlines in which bands of soft and hard rock outcrop at right angles to the coastline.
- Due to the presence of soft and hard rock, differential erosion occurs, with the soft, less resistant rock (e.g. shale), eroding quicker than the hard, resistant rock (e.g. chalk)
- Where the erosion of the soft rock is rapid, bays are formed
- Where there is more resistant rock, erosion is slower and the hard rock is left sticking out into the sea as a headland.
- The exposed headland now becomes vulnerable to the force of destructive waves but shelters the adjacent bays from further erosion.

Named Examples of Headlands and Bays: (LEARN!)

The Dorset coast has excellent examples of Headlands and Bays
e.g. Swanage Bay and the Foreland (a headland)


Once a headland has formed it is then exposed to the full force of destructive waves and it gradually begins to erode. you need to be able to describe the erosion of a headland and the features that form.

For the sequence of formation see the animation below:

So how does a headland erode and caves, arches, stacks and stumps form?

- Firstly, the sea attacks the foot of the cliff and begins to erode areas of weakness such as joints and cracks, through processes of erosion such as hydraulic action, wave pounding, abrasion and solution;
- Gradually these cracks get larger, developing into small caves;
- Further erosion widens the cave and where the fault lines runs through the headland, two caves will eventually erode into the back of each other forming an arch, passing right through the headland.
- A combination of wave attack at the base of the arch, and weathering of the roof of the arch (by frost, wind and rain), weakens the structure until eventually the roof of the arch collapses inwards leaving a stack, a stack is a column of rock which stands separate from the rest of the headland.
- The stack will continue to erode, eventually collapsing to form a stump which will be covered by water at high tide.

Named Examples:

The Foreland (Dorset Coastline) is a great example of a headland which shows these features - there is a distinctive stack called Old Harry and a stump known as Old Harry's Wife.

A good example of a distinctive arch, also found on the Dorset Coast is Durdle Door.


Cliffs are steep rock faces along the coastline, they tend form along concordant coastlines with resistant rocks parallel to the coast.

So how do cliffs and wave-cut platforms form?

- The erosion of a cliff is greatest at its base where large waves break - here hydraulic action, scouring and wave pounding actively undercut the foot of the cliff forming an indent called a wave-cut notch whilst the cliff face is also affected by abrasion as rock fragments are hurled against the cliff by the breaking waves.
- This undercutting continues and eventually the overhanging cliff collapses downwards - this process continues and the cliff gradually retreats and becomes steeper.
- As the cliff retreats, a gently-sloping rocky platform is left at the base, this is known as a wave-cut platform which is exposed at low tide.

Named Examples:

Good examples of cliffs and wave-cut platforms can be found at Hunstanton (North Norfolk) and Flamborough Head (Yorkshire)


Remember - for each erosion feature try and learn a labelled diagram to show its formation, make sure that you also mention examples of erosion processes when describing how the features are actually formed. Finally to access the highest marks remember to name and locate examples of each feature.

- Swanage Bay (Dorset Coast)
- The Foreland (Headland) (Dorset Coast)
- Old Harry (Stack) (Dorset Coast - off of the Foreland)
- Old Harry's Wife (Stump) (Dorset Coast - off of the Foreland)
- Durdle Door (South Dorset Coast)
- Cliffs and Wave-cut platforms - Hunstanton (N Norfolk) and Flamborough Head (Yorkshire)

Click here for examples of 6 mark answers on the formation of coastal erosion features

Follow up Links:
Erosion of a Headland
Animations of Cliff formation
Cliff Features and Arch Animation

Podcast: Coastal Defences
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Coastal Processes: Erosion, Transport and Deposition

Remember, there are 3 main processes that cause a coastline to change:
1. Erosion
2. Transport
3. Deposition.

There are number of factors which affect each of these processes - we are going to start by exploring erosion processes and the factors that can affect the amount of erosion that may take place along a coastline.


Erosion Processes:
Erosion is the wearing away of rocks, at the coast there are 6 main types of erosion processes in action (see animations here):

1. ABRASION (this is also known as corrasion) - this is where rock fragments are hurled at cliffs by breaking waves, gradually scraping away at the cliff face;

2. HYDRAULIC ACTION - as waves break against the cliff face, the pressure of the breaking wave can compress air in cracks. This compressed air gradually forces open the crack in the rock - as this process continues, the rock becomes increasingly weakened.

3. SOLUTION (this is also known as corrosion) - this occurs where the salt water is able to dissolve some of the chemicals in rocks - for example, limestone cliffs are gradually weakened as the salt water dissolves the calcium carbonate in the limestone.

4. SCOURING - this occurs at the base of the cliff as the waves break and swirl around, gradually removing loose rock.

5. ATTRITION - this is where rock fragments carried by the waves hit against each other and gradually wear down to form sand and silt

6. WAVE POUNDING - the sheer force of waves hitting against the cliff face

These processes of erosion form a series of distinctive landforms at the coast.

Rates of Coastal Erosion
So what are the factors that determine how much erosion can take place at the coast?

1. The Resistance of the Rocks - e.g. limestone, chalk and granite are resistant rocks (often forming cliffs and headlands) and erode relatively slowly, whilst less resistant rocks such as clay are easily eroded.

2. The Strength of the waves - affected by the wind strength and duration and its fetch

3. The shape of the coastline (which is dependent on its geology) - on concordant coastlines, rocks are parallel to the wave front and therefore rates of erosion are similar along the coastline. On discordant coastlines, differential erosion may occur, where bands of hard and soft rock outcrop at right angles to the sea. Consequently headlands and bays form along discordant coastlines and whilst headlands remain exposed to the force of the waves, bays are sheltered.

Click on the diagram below for a summary of factors affecting coastal erosion


The second process operating at the coast is transport. Material eroded by the sea is carried within the water in a number of ways, minerals dissolved from rocks are carried in solution, whilst small rock fragments, light enough to be held within the water, float in suspension. The largest rock fragments which are too heavy to be picked up by the waves, are transported by the process of traction, this is where they roll along the bed when the waves pick up enough energy. Finally, medium sized rock particles, which cannot be carried by the waves all the time, are moved by saltation. This is where during times of higher wave energy the particles are picked up and then dropped again as the wave looses its energy.

The main form of transport operating at the coast is that of LONGSHORE DRIFT.

Longshore drift is the process by which sand and pebbles are moved along a beach by the movement of the waves.


Material is moved up the beach by the swash at an angle which is controlled by the prevailing wind. The backwash then carries material back down the beach at right angles to the coastline under the influence of gravity. Gradually the material is moved along the coastline, its direction being controlled by the prevailing wind direction.

The final process operating at the coast is that of deposition - this is where material that is too heavy to be transported any more is left behind, building up the beach. Due to the importance of energy in transporting sand and shingle, it is the largest material that is deposited first. A number of distinctive features may form due to coastal deposition.

Follow up links:
Animations of Coastal Erosion Processes (BBC Bitesize)
Transport and Deposition (BBC Bitesize)

Key Terms Check:
Erosion - the wearing away and removal of material
Deposition - the dropping of material
Abrasion - the wearing of rock due to rock fragments being hurled against cliffs
Attrition - the breakdown of rocks as they hit against each other
Hydraulic Action - the force of waves causing rocks to split apart as waves compress air in cracks in the rocks
Wave Pounding - sheer force of water hitting rocks
Solution - where minerals in rocks are dissolved by the action of sea water
Scouring - occurs where water and broken rock fragments swirl around at the base of cliffs gradually wearing rock away.
Longshore Drift - the movement of material along a coastline

Podcast: Coastal Processes
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Coasts - Energy at the Coast

The coast represents the metting point between the land and sea. Coasts are very dynamic areas and they are constantly change. This change is due to 3 main processes which operate at the coast, 1. Erosion; 2. Transport and 3. Deposition. These 3 processes are all driven by the amount of energy that is available at the coast. The main agents of change at the coasts are waves. Waves are movements of energy throughout the water, but where do waves get their energy from? The answer to this is wind.

As wind blows over the surface of the sea, it creates friction. This frictional drag causes water particles to begin to rotate and energy is transferred forward in the form of a wave. Whilst the water moves forward, the water particles return to their original position. As a wave reaches shallow water, friction between the sea bed and the base of the wave causes the wave to begin to slow down and its shape becomes more eliptical. The top of the wave however, unaffected by the friction, becomes steeper until it eventually breaks. When the wave breaks, water washes up the beach, this is called the swash. The movement of water backdown the beach is called the backwash.

It is the rate at which waves reach the coast which determine whether the main process acting on the coastline is erosion or deposition. There are two main types of waves:

(i) CONSTRUCTIVE WAVES - tend to arrive at the coast at a rate of less than 8 waves per minute, they are low energy waves and are small in height. They have a strong swash and a weak backwash. This means that constructive waves tend to deposit material and build up a beach.

(ii) DESTRUCTIVE WAVES , have much higher energy and tend to arrive at the coast at a rate of more than 8 per minute. They are much larger in height often having been caused by strong winds and a large fetch. These high energy waves have a weak swash but a strong backwash, which erode the beach but pulling sand and shingle down the beach as water returns to the sea.

There are 3 main factors which will affect the strength of a wave and therefore whether it is more likely to erode or build up the coastline:
(i) the strength and speed of the wind - the faster the wind, the more energy is transferred and therefore the bigger the wave that is produced.
(ii) the duration of the wind - this is the length of time for which the wind has blown - the longer the wind blows, the more energy is transferred to the wave
(iii) the fetch - this is the distance over which the wind has blown and therefore how far the wave has travelled. The longer the fetch, the larger the wave is likely to be.

Follow up links:
Excellent Animation showing a wave forming and breaking (Wycombe High School)
Wave Machine Simulator - create your own ocean wave
Ocean Surface Wave - Wikipedia
Waves - includes animation of swash and backwash (BBC Bitesize)
Constructive and Destructive Waves Animation (Wycombe High School)

Key Term Check:
Swash - the movement of water and material up the beach (in direction of prevailing wind)
Backwash - the movement of water and material back down the beach (straight back down due to gravity
Constructive wave - low energy wave with greater swash than backwash - tends to build up the beach
Destructive wave - high energy wave with greater backwash than swash - tends to erode beach

Podcast: Energy at the Coast - Wave Formation
You can listen to a podcast of this post below - to download a copy to listen to on your .mp3 player click here.

Wednesday, August 15, 2007

The Interdependence of Settlements: Case Study - St Ives

You need to be aware of the interdependence of settlements within a hierarchy, with reference to the sphere of influence of places and the types and order of services that they provide. The map below shows the local area around St Ives which includes surrounding towns, villages and hamlets. The sphere of influence of St Ives incorporates many smaller villages including Somersham, Needingworth, Bluntisham, Holywell, Fenstanton and Hemingford.

Image produced from the Ordnance Survey Get-a-map service. Image reproduced with kind permission of Ordnance Survey and Ordnance Survey of Northern Ireland.

Click on the image below to download a .pdf copy of the sheet showing the hierachy of settlements and services provided within which St Ives is part.

Settlement Hierarchies

Settlements within an area vary greatly in physical size, population and the number of services that they provide. When studying settlements within an area we can look at them in terms of a settlement hierarchy. A settlement hierarchy is when settlements are put into an order based upon their size or the services that they provide for people (see hierarchy diagram below). As you go up the hierarchy there is an increase in the size of the settlement, population and number of services; the distance between these settlement types also increases. The number of settlements of each type however decreases as you move up the hierarchy.

Settlements in the hiearchy are interdependent as people will use a variety of services found in different settlements. The area served by a particular settlement is known as its sphere of influence. The size of this will be dependent not only on the type and number of services offered by a town but also the size of the town and the ease of access related to the available transport networks serving the area. Villages usually provide few services, and those that exist are mainly low order services or sell low order goods. Low order goods / services are those that are low in value / cost and are used / required daily, for example milk / newsagents. Larger towns and services will have a greater range of services, including both low order and high order goods and services. High order goods and services are more expensive in nature and not required so frequently. They are often comparison goods, such as furniture, electronic goods etc. and people are usually prepared to travel further in order to get them. The distance that people are prepared to travel to use a service or obtain a good is known as its range. Services such as hypermarkets and goods such as furniture have a much greater range than for example a newsagents and milk.

In order to be profitable, a shop or service will require a minimum number of potential customers, this is known as its threshold population. Shops/services providing low order goods or services usually need a much lower threshold population (as the goods / services are required / used daily), whilst high order shops / services will require a much greater number of potentail customers and thus have a higher threshold population. Marks and Spencers for example may require a threshold population of 70,000 before the store can be profitable.

The needs of local communities are often provided for by neighbourhood shopping centres. These consist of a group of low order shops and services, e.g. a newsagents, bakery, hairdressers etc. serving an area within a town, for example Kings Hedges, St Ives. Out-of-town shopping centres which usually contain higher order shops, including large chain and department stores have increased in number and size significantly over the last 20 years or so and in doing so have had a negative on some nearby town centres.

Follow up links:
Settlement Hierarchy (BBC Bitesize)
Settlement Hierarchy (Wikipedia)
Shopping Hierachies

Key terms check:
Settlement Hierarchy - where settlements are put into order based upon their size or services provided.
High Order Goods - usually high cost goods - bought now and again - e.g. furniture
Low Order Goods - usually low cost goods needed often - e.g. milk
Sphere of Influence - area served by a settlement
Neighbourhood Centre - a group of low order shops serving a community within a town
Range of a Good - maximum distance people are prepared to travel to obtain a service
Threshold - minimum number of people needed to ensure that demand is great enough for a service to be offered

Second Homes - Social and Economic Impacts

Increasing disposable incomes have resulted in an increase in second home ownership. Many of these homes are used for weekends or holidays in attractive rural areas. The increase in second home ownership has however bought some ill feeling by locals who have felt the impact of changes in villages caused by second homes. An increase in second homes in an area can bring both benefits and problems.

- provides trade for local trades such as builders, plumbers etc.
- tourists
- existing home owners have seen an increase in the value of their homes
- older properties in need of repair have been restored
- tourists do bring in some money to the local area

- house prices increase due to competition between buyers of second homes causing many youngsters to be outpriced from their own local area
- villages can become 'sleepy' as some houses remain empty for much of the year - this has also resulted in the closure of some local shops and services due to a fall in demand
- a reduction in public transport services
- some gentrification / improvements carried out by second home owners are not in keeping
- reduction in community spirit as some houses stay empty for long periods and people are without neighbours

Many people have very strong views on second home ownership, as shown in these quotes on the BBC Devon website. Many villages in popular tourist areas such as Devon and Cornwall have seen a signficant increase in properties bought up as second homes. Increasingly young people are finding it difficult to buy homes in the areas they have grown up in due to the rapidly increasing house prices. There have been various calls for the increasing taxation of second home owners to try and reduce the problem. See some of the articles below for specific examples of the problems and some of the solutions that have been proposed. In an exam answer try and name a specific example of an area affected by second homes - e.g. the village of Appledore (Devon).

Key terms check:
Second Home -
a home used only at certain times of the year - e.g. weekends / holiday periods

Follow up links:
The impact of second and holiday homes (an interesting research paper - looks at the socio-economic impacts and impacts on the local housing market)
Second Homes squeezing out locals in Scotland (Scotsman Article)
Holiday Homes causing resentment (Devon) (BBC Article)
Tax urged on Second Home Owners (BBC Article)
Second Homes damage village life (BBC Article)
Your views on second homes (Devon) (BBC)
Second Homes (Geography Pages)
Call for more tax on second homes (BBC Article)
Home, Second Home (BBC Article)

Photo Credit: many thanks to Ian Murray - Geography Photos

Counterurbanisation - Causes and Consequences

Urban to Rural Migration

Since the 1960s there has been a continuing trend of urban to rural migration, with people leaving cities and moving into countryside areas, this process is known as counterurbanisation.

Causes and Consequences of Counterurbanisation

(i) Causes
For your GCSE you will need to understand what is meant by counterurbanisation and you will need to be able to describe the causes and consequences of this process. So why are more people moving from urban areas into the countryside? (the reverse trend of what is happening in many LEDCs where rapid rural-urban migration has been taking place since the 1950s/60s!). The reasons for the movement can be summarised as a set of push and pull factors:

Push Factors (reasons for the movement away from cities)
- higher rates of congestion and pollution
- high land values making it harder for people to find affordable housing
- higher crime rates

Pull Factors (reasons for movements to the countryside)
- perceived better quality of life
- believed to be a safer and more pleasant environment for children to grow up in
- less pollution and more open space
- lower land-values and more affordable housing
- more businesses locating on greenfield sites to make the most of room for expansion and the more pleasant environment.

Improvements in transports and technology have led to the increase in counterurbanisation as it has become easier for people to commute to work or indeed work remotely from home, using internet / fax / e-mail technology.

(ii) Consequences

The process of counterurbanisation has had a number of consequences and in particular has resulted in the changing characteristics of many villages which have seen an increase in population becoming more suburbanised in character. These suburbanised villages have seen various changes as people have moved in from the city. Many have lost some of their rural characteristics as new housing developments have been built and in some instances business units have developed. Village shops and local services often suffer as these settlements often become "dormitory villages", where a large proportion of the population commute to work leaving a small daytime population. Many commuters use large supermarkets on the edge of towns and the lower demand for villages shops and services has forced many to close. There are also social impacts, as once tight-knit communities begin to lose community spirit as more and more people move in.

You should be able to illustrate an answer on suburbanised villages with a case study - e.g.
Peter Tavy, Devon
- experienced the gentrification of existing housing, including several barn conversions
- infrequent bus service (many households with one or two cars)
- need for more low cost housing for young people
- has experienced the closure of local facilities - village shop closed
- increase in newcomers not participating in village life

For more detail on the process of counterurbanisation see the powerpoint below:

Key terms check:
Counterurbanisation - the process of people from cities and towns into the countryside
Suburbanised Villages - villages growing in size and taking on more urban characteristics

Follow up links:
Definition of a suburbanised village

Green Belts - controlling urban sprawl

To restrict development on greenfield sites (sites that have not previously been built on), urban sprawl has been constrained by the creation of Green Belts. Green Belts were created in 1947 as 'collars of land' around urban areas where development is severely restricted to preserve the character of the environment.

Whilst green belts have successfully slowed urban sprawl, in some cases they may protect land of little value, whilst development 'leap-frogs' the constraints of the green belt and begins to grow on the higher quality land beyond it.
Wedges of protected land, as opposed to a surrounding 'collar' have been suggested as a way of allowing controlled growth, whilst protecting high-quality land. Indeed the debate about the future of greenbelts has increased and campaigners are trying to protect greenbelt land.

There are concerns in a number of areas, as further urban development threatens the existing Green Belts. Countryside around both Stevenage and Cambridge is under threat due to plans for the development of new homes, whilst other areas are under threat from other types of development, including plans for a park and ride scheme on the edge of Cambridge.

Case Study: Pressures on the Cambridge Green Belt

In the 1990s, increasing competition for land at the rural-urban fringe to create more jobs and houses, put pressure on green belt areas to release more land.

Cambridge is a famous, historic city with many job opportunities available, easy access to other places and pleasant surrounding countryside. It is protected from urban sprawl by a green belt.

  • - increase in population have previously been dealt with by increased suburbanisation of villages and the creation of new settlements, e.g. Bar Hill and Cambourne, and the newly designated Northstowe (which begins construction in 2008)
  • - over the next 15 years, 42,000 houses need to built in Cambridgeshire to accommodate the increasing population - putting great pressure on the Green Belt
  • - current Green Belt is designed to prevent the mergence of neighbouring settlements, protect the countryside and maintain the character of the city of Cambridge
  • - review of the Green Belt was carried out in 2001 to assess its present success and areas which could be released for development in a sustainable way
  • - the current proposal for development includes 8,000 homes on the edge of Cambridge on land currently in the Green Belt
  • - other options still include, the creation of new settlements and the development of nearby market towns
The key question for debate is whilst provision of new houses is putting pressure on land, should we build on Brownfield sites (areas previously built on which have been demolished) or Greenfield sites (area of countryside, previously never built on)

Why build on Brownfield Sites?
- many areas have unoccupied houses which could be upgraded
- brownfield sites already have utilities such as water and gas pipes
- development in urban as opposed to rural areas can help reduce reliance on cars

Why build on Greenfield Sites?
- cheaper to build on (don't have demolition costs) and lower land-values than in urban areas
- generally perceived as better quality of life in the countryside

Follow up links:
How GreenBelts have benefitted Britain (BBC Video)
"Elastic Band" Green Belt Claim (BBC Article)
Is the Greenbelt an outdated concept? (BBC Article)
Radio 4 News Report - "Is the Greenbelt an outdated concept?"
Warning over Green Belt Hunger (BBC Article)
Is the Green Belt getting 'looser'? (BBC Article)
Green Belt 'at risk of homes' (Gloucesteshire) (BBC Article)
New Developments in the Cambridgeshire Area (linked to Urban sprawl)
Cambridge Green Belt Study
A 'green and pleasant' land (BBC) Article)
Brownfield Land Development

Key term check:
GreenBelts - countryside area around an urban area which are protected from development to restrict urban sprawl
Brownfield Site - an area of land previously build on where developments have been demolished and new building can take place
Greenfield Site - an area of countryside never built on before

Out Of Town Shopping Centres

Since the 1980s, much of the retail development in the UK has been in the form of out-of-town developments as lower land-values, the availability of land for expansion, a nearby labour force and good access routes on the rural-urban fringe of settlements has encouraged out-of-town centres to develop. These out-of-town centres, contain large, well-known stores and often have attractions for all the family, including leisure facilities, catering outlets etc. The growth of these development has however led to a number of common problems which include:

  • - traffic congestion in the vicinity of the new developments
  • - larger stores are often attracted away from nearby town and city centres to these new centres
  • - more empty shops in town and city centres (often attract vandalism)
  • - fewer people visiting the city centres - resulting in the creation of a 'dead heart', particularly in smaller market towns and economic decline
City centres have been fighting back against out-of-town developments through 'shop local' campaigns and in 1998, there were calls by the government to stop out-of-town developments, however there have more recently been proposals for relaxing the resulting planning laws which would make it easier for superstores to build out-of-town developments. Other attempts to reduce town centre decline include calls to abolish free car-parking in out-of-town developments to encourage shoppers back to the town centre.


Meadowhall shopping centre is a large out-of-town shopping centre that has been developed on the outskirts of Sheffield. It was built in the late 1980s as a response to the lack of shopping provision in the area. It was constructed on a brownfield site (56 hectare site of a former steelworks). Access to the shopping centre is excellent and it is close to several large urban areas with 9 million people living within an hours drive of the centre (see map opposite).

Why this location?
  • plenty of space for expansion and for providing large free car parks
  • rates and rents are lower than in the city centre (shops can be bigger) - i.e. cheaper land on edge of Sheffield
  • near to suburban housing (provides a labour force)
  • near a number of motorway intersections (nearbly M1/A roads) - great accessibility and access to large sphere of influence
  • old brownfield site (was a steelworks) with plenty of room for expansion if required

The main characteristics of the shopping centre:
  • bright and modern with many different faciliites, including a leisure centre, cinema, creche and other attractions for children;
  • a large variety of shops;
  • large, free car parts (12,000 spaces!)
  • provides under-cover shopping (not restricted by weather and shoppers, shop in the comfort of an air-conditioned complex)
  • supertram link with the city centre;
  • two new railways stations built
(photo (c) Ian Britton -

The Impact of Meadowhall on Sheffield?
The building of Meadowhall has had an impact on Sheffield City Centre, as many shops have moved out and takings have been down for some shops by as much as 25%. This good article on Geography Pages summarises the issues for the centre.

EXAMPLE 2: BLUEWATER - nr Dartford (Kent)

Bluewater, known as Europe's largest retail and leisure complex, opened in 1999, it was built on a brownfield site, in a disussed chalk quarry and has excellent access, being just outside the M25 in the area of Dartford. The following powerpoint gives more detail about the location and features of the out-of-town shopping centre as well as giving some consideration to the criticisms the centre has come under

Other examples of out-of-town shopping centres include:
Lakeside - East of London
Brent Cross - NW London
Metro Centre - Gateshead
Merry Hill - Dudley (Birmingham)

Follow up links:
Meadowhall Virtual Visit (by Holgate School - good overview)
Superstores 'killing' market town shops (BBC article)
Parking tax on out of town shoppers to save the high street (Times Article)
How has Sheffield City Centre changed since the development of Meadowhall (Geography Pages)
Proposals give supermarkets an easy ride to out of town centres (Time Article)
Meadowhall Website
Bluewater Website

Key Term Check:
Out-of-town Shopping Centres - large retail developments found in out-of-town locations close to major transport links.

The Rural-Urban Fringe (Land-use and conflict)

The rural-urban fringe (the area at the edge of a city) has become an increasingly popular area for economic developments. Competition for land in these areas increased signficantly during the 1990s. The land is much cheaper here than in the city centre, and many factories that were once in inner city locations have moved to these areas as their previous locations lacked space for expansion. As well as industrial estates and residential use, these areas attract shopping centres, business parks and recreation facilities such as golf courses. The benefits of the rural-urban fringe are set out in the diagram below.

Conflict at the Rural-Urban fringe
Although there is competition for land for economic developments at the rural-urban fringe, there is increasing pressure from environmental groups to restrict urban sprawl and protect the environment on the edge of cities from economic pressures. If urban sprawl continues unchecked, many wildlife habitats would be destroyed. Conservationists and farmers want to protect nature reserves and farmland, and open space for recreation is required by people living in the nearby urban area. There is therefore competition for land at the rural-urban fringe and conflict between economic and environmental land-uses. You should be aware of these and be able to discuss them in an exam answer.

There have been a number of attempts to control urban sprawl and reduce / restrict developments on the rural-urban fringe, these include Green Belts which were created by the government in 1947.

Follow up links:

Rural-urban fringe (definition)
The Rural-Urban Fringe (a detailed article really aimed at A'level students - but with many useful points)
Land-use at the rural-urban fringe (a detailed report from the Farm Foundation summarising policies and issues associated with land-use at the rural-urban fringe)
Urban Land-use Model (GeoBytes)

Key Terms Check:

Rural-urban fringe - where urban areas meet the surrounding countryside
Green Belt - an area of land around a settlement where development is severely restricted
Urban Sprawl - uncontrolled growth on the edge of a settlement
Greenfield Site - land previously unbuilt on

Suburbs - the growth and characteristics of


Since the early 20th century, cities have continued to grow outwards into the countryside. This is the process of suburbanisation as new residential areas are created at the edge of the city. This new growth surrounded the old industries and low-class residential areas giving them an inner-city location. In the 1920s/30s many of the middle classes moved out of the inner city areas buying houses along main roads / railway routes from the centre (ribbon development)

Reasons for Suburban Growth:

  1. Better public transport and increased car ownership meant people could separate work from where they live
  2. Building societies provided mortgages making it easier to buy homes
  3. People were better off and looking for a better living environment
The continued outward growth of cities is also known as urban sprawl. Early suburban growth (1920s/30s) forms the inner suburbs, as it has now been encircled by further growth (1960s/1980s) which form the outer suburbs.

Characteristics of the Inner Suburbs

Although some inter-war housing was built as estates, ribbon development, laong main roads into the city was common. The photograph below is a typical example of a inner suburban landscape (with housing dating back to the 1920s/30s). Compared to the inner city there is much greater owner-occupancy as people bought their own homes.

The typical characteristics associated with the inner suburbs are shown below (photo courtesey of :


Urban Sprawl has continued to enlarge towns and cities, with continued growth at the rural-urban fringe (where the countryside meets the urban area). Residential development on thsi outer fringe forms the outer suburbs. As a result of policies in the 1960s to clear inner city slums, some outer city council estates can be found in these areas.

There are also many private residential estates. Many of these estates were built between the 1960s and 1980s and provide high-quality, low density housing. There is more open space avaialble and a much higher quality living environment. The houses are large and usually either semi-detached or detached. The houses have gardens and garages and are modern in design as well as the amenities they provide. The photograph below highlights the main characteristics that are typical of housing in the outer suburbs.

The typical characteristics associated with outer suburb areas are shown below (photo courtesey of :

Follow up Links:

Urban Land-use Model (GeoBytes)

Key Term Check:

Inner Suburbs -
residential area surrounding the inner city, characterised by semi-detached houses and tree-lined streets
Outer Suburbs - residential area towards the edge of a city, characterised by larger often detached houses and modern housing estates.
Urban Sprawl
- the uncontrolled growth of an urban area into the surrounding countryside
- an area of housing