- Corrosion/Abrasion – The breaking waves scoop up stones and fragments of scattered rock and hurl these at the cliffs. This has the effect of chipping away at the rock, which leads to them eventually falling off.
- Scouring – Wave which break at the base of a cliff and swirl and remove loose rock with the strong current.
- Hydraulic Action – The pressure exerted by breaking waves traps and compresses air in cracks. The intense pressure forces open the cracks further so weakening the rock.
- Solution – Some rocks have a chemical composition which salt can dissolve. In chalk and limestone, calcium carbonate is dissolved, so weakening the rock.
- Attrition – The waves swirl rock fragments and as they collide they wear down. Eventually the fragments are reduced to sand or silt. Often, these rounded fragments are sorted by the sea into depositaries according to their size. The heaviest and largest material is left near the cliff. The sea moves, grades and deposits other material according to size away from the cliff so the finest material is deposited as sand off the coast.
The material produced by weathering and erosion is moved by waves along the coast and out to sea. Longshore Drift provides the responsibility for the wearing down and building up of the coastline. The movement of beach material gradually accumulates to form distinctive features including spits, tombolo, beaches and bars.
When a wave breaks up to the beach at an angle, we identify the fact that Longshore Drift is at work. The process of the wave going up the beach is called swash; it approaches the coast at an angle. However, the backwash (the movement of water back into the sea after the swash), flows straight back due to the beach’s slope. A pebble moving along the beach would move in a zigzag path.
Swash Backwash
Longshore Drift Diagram – This diagram represents the movement of Longshore Drift from one end of a beach to the other. The big arrow indicates the direction of beach material movement
Longshore Drift & Its Properties
The rate of movement depends on several factors; the strength of the waves, the size of the material being moved and the beach incline. Larger waves are able to move larger sediment. But if there is a very gentle slope to the beach slope or the waves lack energy, little Longshore Drift will take place.
Material is moved by waves in many different ways. This depends on the materials size and how much energy the waves has stored.
- Solution – Salts and other minerals dissolved from the rocks.
- Suspension – Finer materials can be carried in suspension by waves.
- Saltation – Material which is just too heavy to be carried in suspension and will be bounced along.
- Traction – Heavier material is rolled along the seabed by the strongest waves.
The formation of Porlock Bay has changed over recent years. In 100,000BP the Bristol Channel started to erode Porlock Bay via attrition. Porlock Bay is made of three different rock types; Sandstone (resistant), Clay (soft) and Limestone (resistant). These 3 rocks over the years have changed a lot. Rocks such as Sandstone and Limestone are resistant to erosion. These rocks will form headlands and cliffs. Soft Rocks like clay are to be eroded. The Sandstone part of Porlock Bay, on the west, which is now Gore Point, has now started to form as a headland. The Limestone part of Porlock Bay, on the East, which is now Hurlestone Point, has now started to form as a cliff.
{PORLOCK BAY MAP HERE – sheet 1}
{Porlock bay skth} sheet 2
Porlock Bay in the year 100,000BC
Porlock Bay to the present day
Gore Point Hurlestone Point
From the diagram above we understand that over the period of time: 100,000BC to the present day, the Bristol Channel has eroded Porlock Bay. The attrition, which has played a major part of the erosion of Porlock Bay, has only eroded the soft rock, in this case the clay between the Gore point and the Hurlestone Point, but the resistant rocks, such as Sandstone and Limestone have resisted the erosion forces and have become steep cliffs and headlands.
Coast Sea Headlands
Porlock Bay Beach – Includes a picture of headland, sea and pebble beach.
The Exmoor Coastline stretches some 30 miles between Minehead at its eastern end and Combe Martin to the west. For most of this distance the coastline is formed mainly of cliffs but at Porlock the land flattens out and a unique mile long shingle ridge and an inland salt marsh have formed.
Wave – The arrow shows the direction of the wind, which is creating this wave.
Porlock Bay is on the North Somerset coast. It is in Exmoor National Park. The west half of Porlock Bay is owned by Mark Blathwayt of Porlock. The east half of Porlock Bay is owned by National Trust (a charity).
I shall explain 4 different forms of sea defences.
Num 6 ere
An overview of Porlock Bay and the headlands
Beach Nourishment – This technique consist of an eroding beach almost being re-built using material from elsewhere. It does not fully cure the effect of the sea eroding the land. Therefore, it may need to be a continual process or to be repeated at regular intervals.
In 1992, the Posford Driver Report also favoured taking material from Hurlestone Point. They considered a number of alternatives:
- Bringing in material from land-based quarries. However, it was estimated that it would cost about eight times more than if they were to use local material – this was obviously not economically sensible.
- The removal of the groyne west of Porlock Weir Harbour, estimated by Carter to be a major contributing factor in the reduction of beach material further east. This alternative also had its disadvantages: it was felt that not enough material would be released to repair the beach and that if any material had been removed from this site, it could put the Turkey Cottages at risk.
- To transfer material from in front of Gibraltar Cottages. This was also felt that it would put the cottages and the adjacent area at risk.
- To transfer material from Bossington Beach, the area owned by the National Trust and suggested in the Halcrow Report. It was suggested that the pebbles could be removed from the seaward face, avoiding any ecological damage to the back of the ridge.
Cost – To nourish the beach initially using pebbles from within Porlock Bay and to carry out annual maintenance in order to achieve
-A 30-year standard protection, which estimates to an approximate value of £342,000 - £432,000
-A 50-year standard protection, which estimates to an approximate value of £367,000 - £471,000.
Groynes - Groynes are structures; often wood, which are normally installed at right angles to the beach with the intention of reducing or stopping Longshore Drift (commonly known as LSD). However, the installation of groynes can lead to further erosion along the coast.
Porlock Bay, since 1824, have been using groynes to stabilise the ridge but most of the groynes visible in 1998 result from improvement schemes which were carried out between 1967 and 1971. It was thought that this scheme was highly effective but the main trouble spots remained.
Cost – Groynes normally cost £10,000 each, and would be needed in every 200m intervals along the length of beach at risk.
Offshore / Submerging Breakwaters – This involves the construction of breakwaters parallel to the shore in the area of foreshore between high and low tide. The height of waves approaching the shore is reduced by the breakwaters, thus reducing the amount of wave energy reaching the upper shore. The decrease in energy results in less erosion.
In the case of Porlock Bay, offshore breakwaters would protect the shingle ridge from wave action and would reduce the amount of Longshore Drift without stopping it completely. Offshore breakwaters were one of the proposals contained in the Halcrow Report of 1985.
Cost – Submerged breakwater at Porlockford - £896,000
Submerged breakwater at New Works - £640,000
The costs are the same for a standard of protection of 30, 50 and 100 years.
Offshore submerging breakwater – causes large waves to break further offshore thus reducing the wave energy on the beach.
Rip-Rap – These are structure built close to the top of the shore and designed to spread out wave energy, thereby reducing the amount of erosion carried out by the destructive waves and often resulting in them becoming constructive. Any stretch of rip-rap needs to be built of boulders of a size sufficient to prevent movement, even under storm conditions.
In the case of Porlock Bay, the proposal contained in the Halcrow Report of 1985 was to use 3 tonne boulders at an angle of 17 degrees at Porlockford and the east of New Works. This type of construction would prevent Longshore Drift until the spaces in between the boulders were filled with shingle. However, their construction might result in increased erosion further east and so some beach nourishment might also be required.
Cost – Rip-Rap at Porlockford - £1,000,000
Rip-Rap at New Works - £448,000
Rip-Rap to protect the whole ridge - £12,000,000
These costs are for a standard protection of 100 years.
Rip-Rap – dissipates wave energy.
In order to stop Porlock Bay from becoming flooded, we have to consider a few alternatives, which has its advantages and disadvantages on the solutions effectiveness.
After analysing this table, which shows the various methods of stopping floods in Porlock Bay, I have come to the conclusion that the first option would be my preference. This is because is does not cost anything and its natural. However, the disadvantages such as floods and the loss of land give it the difficulty to choose, but after the floods, fields often become muddy and salty. This can be benefited from, salt marshes will form creating salt marsh farms, these are very rare in England, and so are wanted by many farmers.
This choice, however, is most probable make people unhappy with the resolving of this issue. Farmers would be pleased as they attain salt marsh farms, which prove to be rare. Residents and local councils would be very upset because they pay tax, which usually goes to the government and from there the money is used to make certain areas into a better place to reside in. Tourists would feel the same emotions as the residents of the area as they may not be used to these certain conditions. This could affect the tourist trade.
Porlock idea map – sheet 5
Hypothesis
If Longshore Drift were taking place in Porlock Bay, I would expect: -
- Removal (erosion) of pebbles at one end and deposition at the other because Longshore Drift deposits materials carried over a period of time along the beach through the swash and backwash movements, so there would be more deposition at one end.
- A decrease in pebble size in the direction of Longshore Drift as the water erodes the stone and makes it decrease in size, also when it is moved through the beach it may hit other beach material. This means that the pebbles are broken down whilst being transported and are eroded by attrition.
- An increase in the pebbles roundness and smoothness. This could also be because of the rock being against attrition.
Method
In order to test the possibility of Longshore Drift occurring and in its direction we had to make tests at 2 certain sites of a pebble beach in Porlock Bay. These sites were the East Side (Gore Point) and the West Side (Hurlestone Point).
Beach Profile
To get accurate data we split into groups so that we could find out fair averages. We, between our groups rotated in doing tasks to achieve our results. The tasks were: measuring pebbles from our random measurements, taking a pebble from random result, measuring facets and using the Clinometer to work out the facets angle.
To avoid any errors and to increase our accuracy in our work and results, we looked from a side on view of the beach to get a better perspective of where a certain facet ends in the beach. We also used two people of the same height to determine the angle of each facet because you have to look through the Clinometer from 1 eye and into the other person eye with the other eye. Whereas, if you were taller or shorter than a person who you are working with and they are at the top of the facet, your results would be a substantial amount different from the beach itself.
If Longshore Drift were carrying beach material from one side of the beach to the other across the bay, we would expect the shape of the beach to be different. So that means that the beach receiving the beach material would certainly be wider, deeper and longer. In order to measure this we would need data on beach profiles. To attain this data you need a few pieces of equipment, such as: -
- Clinometer – which measures the angle of each facets (the breaks n slopes)
- Tape Measure – To measure the facets, also used for the random numbers sheet where we picked up stones from certain measurements within the 30m boundaries.
- Clipboard & Pencil – To write with a pencil on the clipboard about the results we accumulated.
Clinometer – An angle-measuring instrument, shown on the left and the view when you look inside, shown on the right.
Clinometer reads the Viewing Hole When the angle is above or below
Angle on the outside which 0, this indicates the inclination
Provides an easier technique. of each facet as positive/negative.
Sheet 4 – powers index
{BEACH PROFILE GRAPH HERE}
From the graph paper above, which tells us how the beach profile looks, we understand that at low tide, Gore Point has a less amount of facets compared to the Hurlestone Point beach profile. I also analysed the facet angle comparison between the two beaches. Gore Point has more steeper facets, whereas, Hurlestone Point has less steeper facets. The East side of Porlock Bay, Hurlestone Point has longer and more facets than in the west beach.
We recorded each facet and its angle, whilst on the beach here is a table we made with the information on the facets.
In order to measure the length of the facet we used the tape measure, which if stretched, would be of a length approximating 30 metres.
For measurements of a facets angle, we used a completely different instrument called a Clinometer. Its reading is viewed through a hole on the side of the instrument. If the line is below the 0 degree mark than it is a negative angled facet and if it is above the 0 degree mark then, obviously it is a positive angled facet.
[NUM 2 ERE]
This is a picture of the pebble beach in Porlock Bay (Gore Point). Beach facets visible and also the angle of the facet is clear.
Pebble Size & Shape
To find out whether Longshore Drift is existent we also accomplished many more tests. Not only have our beach profiles proved that Longshore Drift occurs but also, the pebble shape and size plays a big, influential role. If Longshore Drift proved to be correct than the size of the pebbles would be smaller as attrition would have eroded the rock. Also the shape could be a variable because the rounder pebbles were laying in the east beach. This proves that Longshore Drift must have taken the rocks from the west to the east beach whilst the seas loose particle chipped away the rock, which formed its unique smooth and rounded surface. To attain this data and information we used a few pieces of equipment. These are some you would use to achieve your aims :-
- Tape Measure – Tape measure would indicate where we would pick a pebble up from according to our random measurements.
- Powers Roundness Index – To establish what roundness the pebble would classify as, there are 6 possibilities; Very Angular, Angular, Sub Angular, Sub Rounded, Rounded, Very Rounded.
- Clipboard & Pencil - To write with a pencil on the clipboard about the results we accumulated.
Num3 here
This is a picture of Gore Point headlands with the pebble beach’s facets.
{my Porlock bay map wit my defence}
Groups were given a start point from the cliff working their way towards the sea.
We were to find out the beach profile of each end of Porlock Bay (Gore and Hurlestone Point), to determine whether Longshore Drift was existent. A beach profile is a side view of the beach indicating the length and angle of each facet.
Each group of five were given a section of the coast to work from. After five groups accumulating results with their tape measures, we had covered the entire beach. We had to follow a random measurements sheet in order to know were to analyse the pebbles from our tape measure this was because it is fairer that we use numbers that we had nothing to do with choosing.
Beach Layout – Indication of the way we set out our tape measures in our groups
Num 5 ere
An picure of working groups
Results
From this ‘Pebble Length’ table we establish that the reasoning above is proven to be correct. The reasoning is that if Longshore Drift were to be occurring then the pebble size would decrease in the direction of Longshore Drift (West to East – Gore Point to Hurlestone Point).
From this ‘Pebble Shape’ table we establish that the reasoning above is proven to be correct. The reasoning is that if Longshore Drift were to be occurring then the pebble shape would become rounder and smoother in the direction of Longshore Drift (West to East – Gore Point to Hurlestone Point).
Results graph – sheet 3
Average result sheet – sheet 6
Num 7 ere
A sample of pebbles at Porlock Bay
At a summit near Hurlestone Point there was a view of the whole of Porlock Bay. At this summit the possible solutions of the situation are discussed. There are a few solutions to the problem.
- Recurved Sea Wall – This type of sea wall is meant to protect the sea by forcing and redirecting the waves back towards the sea. It cost about £6000 per metre to build. The Recurved sea walls, as do the other solutions has its advantages and its disadvantages. The land would never be flooded and the steel rod running through it will prevent any erosion, taking place on this sea wall. At the current moment a sea wall stands in the populated area of Minehead, Porlock Bay. Its effect upon the beach is very positive although it is very unattractive and highly expensive.
Steel Pile Concrete
This Recurved sea wall indicates the structure of which the sea wall is based upon.
- Rock Armour (Rip-Rap) – Rock Armour has been used both as a sea wall and to construct groynes. There is a certain degree of evidence that these forms of sea defences are effective. The indication that at Minehead, water has not passed the sea wall, proves that the sea wall works. The other use of large boulders is in groynes. Instead of using timber pile groynes, the idea of using boulders has come about from the armour aiming to stop Longshore Drift from occurring; also it could be placed in order to dissipate wave energy. The idea evolved after it was suggested as a very sensible defence for Porlock Bay in Exmoor National Park. A major argument against it was a visual instruction along with the fact that it is unattractive.
Large boulders dumped on beach
This diagram of the type of boulders describes the different types of uses for these such as; boulder groynes (instead of timber pile groynes) and a sea wall (instead of a Recurved sea wall made of concrete with a steel pile through which strengthens the structure.
- Beach Nourishment – Beach Nourishment at Minehead, this is meant pumping sand from below the low tide mark. Sometimes sand or pebbles are brought by lorry from other sites. It is a popular method for replacing beaches, which have been eroded by Longshore Drift. It is often used to encourage tourists. It costs about £3 per cubic metre and has to be repeated regularly.
My opinion is based on the circumstances of the condition at Minehead. I personally believe it is not a very substantial option to support Porlock Bay the reasons for this is that simply it is wasting a lot of money on each cubic metre, which adds up to a great deal of money. The main aspect of my negative opinion is that it is to be repeated regularly, which is a disadvantage.
In order of the sea defences presence, we have recorded what the land behind the beach is used, in this case as a tourist resort. The buildings around the beach we investigated in order to find out what they are used as. For example, the red buildings on the map are banks etc. We along with the building use map decided to participate in how many pedestrians walked past and entered a certain shop. We were divided into groups of 12. With each group covering a section around the beachfront. This data was recorded for 10 minutes from 11:00 am to 11:10 am. The second part of this particular investigation was taking place in our allotted sections to write down 20 number plates for five minutes from 11:10 am to 11:15 am. After this investigation we were handed a sheet explaining how the number plate system works and how to find the origin of the car by determining the first or last two letters on a number plate. From this sheet we found cars from : Wales, Scotland, England – North West, North, Yorks & Humberside, East Midlands, West Midlands, East Anglia, South East, London, South West.
Building use map
Peds number map
Peds table of places
Land use type sheet
Car reg. Origin diagram
Analysis
- Aim 1 - To investigate the evidence of Longshore Drift in Porlock Bay, Somerset.
- Hypothesis 1 - Removal (erosion) of pebbles at one end and deposition at the other because Longshore Drift deposits materials carried over a period of time along the beach through the swash and backwash movements, so there would be more deposition at one end.
Pebble length in the class results show that the pebbles are smaller at the east side. This is confirmed by the group results – which are on page 19. Looking in more detail at the class results it is apparent that there are no pebbles larger than 15cm, whereas in the west 5 were more than 15cm. This suggests that the sea or Longshore Drift is moving material from Gore to Hurlestone Point. Longshore Drift must be the process. As the pebbles are transported they are eroded by attrition. This is the smashing of pebbles by pebbles in rough seas. This gradually reduces the size of the pebbles, as they are moved from point to point. My first hypothesis that pebble length will decrease in size is correct.
Pebble roundness will increase in numbers from the west to east. The class results show that most pebbles were sub angular in the west and rounded in the east, this is also backed up by my group results. Taking a closer look at the data in the west all 20 pebbles fall between the Angular to Rounded categories, whereas in the east all 20 pebbles fall between the Sub Rounded and the Very Rounded categories.
In the west 100% are Angular to Rounded while in the east 20% fall in that category. This is backed up by my group’s results on page 19.
These pebbles are from the same type and source of rock. The rocks are located in the cliffs at Gore Point. At that stage they are so loose, they can be picked out by hand. Observations made at the site told me they were all uneven, jagged and angular.
This suggests again that Longshore Drift is taking place. Hydraulic Action has scoured out the angular pebbles during high tide and storms. On their journey to Hurlestone Point they have been bounced along the rocky seabed and banged into each other. This latter process (attrition) takes the sharp edges off and rounds the pebble. This proves my hypothesis and suggests Longshore Drift is true.
An eroded beach would be shallow and would be a depositional beach. This means that Longshore Drift is transferring material from one beach to another. Therefore I expect the east (Hurlestone Point) of Porlock Bay to have a bigger area.
This proves my aim is correct
- Aim 2 - Consider the alternative ways for protecting the land behind Porlock Bay from being flooded by the sea.
There are 4 main options for the Minehead sea defence. They are a recurved sea wall, rock armour, revetments and beach nourishment. They all have their advantages and disadvantages.
According to my chart of results I believe that Longshore Drift is obviously taking place at Porlock Bay but nothing should be done, but Minehead could use a sea defence, as it is a popular tourist resort. The cost of the four possible defences could be very damaging economically, although the defences are very effective in their own ways.
- Recurved Sea Wall – The land behind will not flood and wall will never erode. (£6000 per metre)
- Rock Armour – Dissipates the wave energy, can be used as groynes or a sea wall. (£3500 per metre)
- Revetments – The idea of these is that the wave energy is reduced but to this day most of these are buried by sand. (£2000 per metre)
- Beach Nourishment – Replaces beaches, which have been eroded by Longshore Drift, although this has to be repeated regularly. (£3 per cubic metre)
- Aim 3 - To look at the effectiveness of the Minehead sea defence scheme completed in 1999 at a cost of £12.7million.
At Minehead, Porlock Bay, we understand that they have installed a recurved sea wall and groynes (which are rock armour groynes), which were completed in 1999 for a total of £12.7 million. The effectiveness of the scheme proves to be a positive one. The Longshore Drift in Minehead is not really taking course as much as it is at Gore and Hurlestone Point. The main reason for this is that of the groynes. The function is to be at a right angle from the actual coast and for it to stop as much Longshore Drift as possible, this is however is far different for the reason and aims of why the recurved sea wall is there. Its main function is to stop waves from attacking the land behind the beachfront and to stop any flooding to the popular tourist resort. The wall is meant to roll the water along its wall after it is directed back toward the sea.
The most effective sea defence, in my opinion, is the Rock Armour; I have chosen this because it is very flexible in use. It can be used as beach rocks, groynes or a simple sea wall. Although it is not economical, it is more than worthwhile; also beach nourishment is a sensible form of sea defence for Somerset.
{num 4 here}
Picture of Minehead beach with headlands and rip-rap (rock armour) groynes.
Conclusion
In this whole Somerset trip, where we visited 2 Porlock Bay pebble beaches, Gore Point and Hurlestone Point, and Minehead, I have learnt about Longshore Drift and its properties. After Somerset I have found out that Longshore Drift has many factors in which to show its occurrence, there are, the beach profiles which show an indication of the movement of pebbles throughout a period of time. Another indication of how Longshore Drift is existent is the pebbles shape and size. The pebbles tend to be smoother, rounder and to an extent, fair deal smaller than those of which the direction of Longshore Drifts starting point, this is because of the attrition caused by the sea.
I have learnt about various sea defences for Porlock Bay, with both advantages, disadvantages, costs (per metre) and the effectiveness of each option. I understood the relation between the Porlock Bays circumstance and the variation of choices and how they could possibly work and whether the sufficient amount of effectiveness is there or not.
Also, I thought about the ways of protecting Minehead and the land behind it. I have taken into account the circumstance and how it is a popular tourist resort and I have decided to put Rock Armour as sea walls and beach nourishment to protect the land behind. The Rock Armour is to be used near the area where the swash takes place so that it is able to dissipate the wave energy.
There are a few future implications to the situation in Somerset
- Future Implications - To have as a consequence or necessary circumstance; imply or entail
These implications are basically looking into the future for any aspect, which can change the situation of Porlock Bay and Minehead. We are talking in terms of global warming and its effect of how it can alter our thoughts. It can raise the levels of the sea over time, meaning more money is to be spent on Somerset for its sea defences.
Agricultural land is no longer as valuable as it once was. This is due to the competition throughout the world and a drop in food prices. This leads to saying that Porlock Bay is no longer worth protecting. So, seas should be allowed to flood the area of marshes. This will form salt marsh farms. As for Minehead, tourism is on the increase; this means that wide beaches and promenades are desirable leaving the sea wall (preferably using rip-rap) and beach nourishment as the best forms of sea defence.
Limitations
Five good points :-
- We managed to get all our results.
- The results within each group were around the same, this proved that groups completed aims successfully
- No anomalies
- All proposed tasks and work fully completed
- Co-operation between groups was brilliant. All students participated in at least one activity.
Five Bad Points :-
- We looked at Gore Point at low tide and Hurlestone Point at high tide.
- Working too slow
- Look at the possibility that if Minehead did not have a sea defence, discuss what is inevitable.
- The project could have been improved if we had spent a few more days and seen the two sites and sea if we saw a difference in beach profiles over a few days.
- From the above statement – we could have simply calculated a years change in the beaches after doing a two-day count.
Num 1 ere
The beach at Minehead at low tide, with its rip-rap groynes
The project could have been improved in many ways for instance; we should have recorded both beaches at either high or low tide, instead of doing one of each. This could have been made possible by half of the class went to Hurlestone Point and half remained at Gore Point.
Glossary
Abrasion - Physical wearing and grinding of a surface through and impact by material carried in air, water, or ice.
Accessible – easy to get to.
Adjacent - In close proximity to or neighbouring, not necessarily abutting.
Agriculture - The science, art and business of cultivating the soil, producing crops and raising livestock
Attrition - when waves cause rocks and pebbles to bump into each other and break up.
Backwash - The seaward return of the water following the up rush of the waves.
Beach - The beach is the area between the lowest spring tide level and the point reached by the storm waves in the highest tides. Every beach is different but they are usually made up of material deposited on a wave-cut platform.
Beach Nourishment - artificial process of replenishing a beach with material from another source which lies either inland or may be dredged from offshore.
Breakwater - The quick collapse of an overextended water as it approaches the .
Clinometer – an instrument used to measure angles of facets.
Coastal Deposition - when the sea drops or deposits material. This can include sand, sediment and shingle.
Condition - an assumption on which rests the validity or effect of something
Depositional - The act of depositing, especially the laying down of matter by a natural process.
Dissipate – to separate with a lower amount of energy than before.
Economical - Prudent and thrifty in management; not wasteful or extravagant.
Ecological - The study of the detrimental effects of modern civilization on the environment, with a view toward prevention or reversal through conservation. Also called human ecology.
Effectiveness – The amount of ones intensions successfulness, and how they turned out.
Erode - To wear (something) away by or as if by abrasion: Waves eroded the shore.
Expensive - Requiring a large expenditure; costly.
Facet – a break in slope
Fields - A cultivated expanse of land, especially one devoted to a particular crop: a field of corn.
Flood - Inundation of a land surface that is not normally submerged by water from quick change in the level of a water body like a , , or
Flood Plain – flat land forming the floor of a valley, liable to flooding.
Foreshore - The area of a shore that lies between the average high tide mark and the average low tide mark.
Global Warming - Warming of the Earth's because of an increase in the concentration of . A greater concentration in greenhouse gases in the is believed to result in an enhancement of the .
Groynes - The best form of natural defence is a beach, which efficiently absorbs the energy of the waves. Along many coasts, however, Longshore Drift causes the beach to thin out in places and erosion of the land behind becomes a problem. Groynes are designed to slow down Longshore Drift and build up the beach. They are usually made of tropical hardwoods, which are more resistant to marine borers and erosion. A few are made of concrete, steel or in more recent times large rocks. They are built at right angles to the shore and spaced about 50-100 metres apart. Groynes may have a life of 15-20 years but often have to be replaced rather than repaired.
Headlands - A strip of land that juts from the . This feature normally bordered by a .
Hydraulic Action - When waves hit the base of a cliff air is compressed into cracks. When the wave retreats the air rushes out of the gap. Often this causes cliff material to break away.
Longshore Drift – movement of sand and pebbles along a beach by waves.
Maintenance - The work of keeping something in proper condition; upkeep.
Method - A means or manner of procedure, especially a regular and systematic way of accomplishing something
Ocean - A body of saline water found occupying all or part of the Earth's . There are six recognized oceans: North Atlantic, South Atlantic, North Pacific, South Pacific, Indian, and Arctic.
Pebbles - A rounded piece of that is larger than
Population - All of the people inhabiting a specified area.
Preference - The selecting of someone or something over another or others.
Pressure - The application of continuous force by one body on another that it is touching; compression.
Proposal - A plan that is proposed.
Reside - To live in a place permanently or for an extended period
Resistant - A force that tends to oppose or retard motion.
Resort - A place frequented by people for relaxation or recreation
Revetments - A cheaper alternative to sea walls is the revetment. This is a sloping feature, which breaks up or absorbs the energy of the waves but may let water and sediment pass through. The older wooden revetment consists of posts fixed into the beach with wooden slats between.
Salt Marsh – A salt marsh is a coastal marsh that forms on mud flats. They usually form in very sheltered inlets and estuaries, or behind spits (places where fine sediment accumulates). Salt marshes form as vegetation builds up on these mud flats.
Seabed - The floor of the sea or the ocean.
Seawater - The mixture of water and various dissolved found in the world's and .
Shallow - Measuring little from bottom to top or surface; lacking physical depth.
Shore - The land area bordering a relatively large water body like a or
Solution - when certain types of cliff erode as a result of weak acids in the sea.
Swash - A bar over which waves wash freely.
Tide - the periodic rise and fall of the sea level under the gravitational pull of the moon
Tourists - One who travels for pleasure.
Trade - The people working in or associated with a business or industry
Unattractive - lacking beauty or charm
Wave - A moving swell or ridge on the surface of a solid or liquid or within the medium of a gas.
Bibliography
To do my coursework successfully, I gathered information from many different sources.
Internet – - I took information from the BBC and I moulded it around the work I am currently doing. To do this I changed the words into my own words and based it around the Somerset circumstance.
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- From here I learnt a few concepts in which I added to my glossary section.
Books – The information I took to provide a good explanation was from my class geography text book – “a new introduction to geography” by Keith Flinders.