geography - coasts

why do people live near the coast?

• less pollution
• views/scenery
• tourism
• cleaner
• more job opportunites

How has the port in southampton helped it to grow?

Exports and imports, which tons of cargo are shipped through every day and it is the second largest container port in the U.K, and also benefits from a sheltered location and a unique double tide.

Deep water port

largest oil refinery was built

excellent port

attracts many companies

other companies see opportunities

more jobs

It also benefits from having a natural harbour, which ships can be loaded and unloaded easily, creating more economic opportunities. 

How does the economic development of coastal areas affect the environment?

• Large boats

They create lots of air and noise pollution, oil leakages can occur and the anchors dragging along the sea bed disrupts it and destroyed ocean wildlife

• tourism

Pollution of the air with more fumes, less food and erosion of walkways.

• Factories

noise and air pollution, fumes causing pollution and congestion.

Land uses of southampton:

hospitals, football stadiums, ocean village, trainstations, cruise liners and universities.

Waves: They are created by the moon and the wind and are formed because of the friction on top of the ater.

Erosion: is created by waves crashing against the cliff side which erodes it away over years; it can be either fast or slow, depending on the rock type.

Weahering: The break down of rock by the action of weather, plants or chemical action, and example is freeze-thaw.

Hydraulic action: The sheer force of a wave breaking against a cliff, causing parts to break away whilst the air is being compressed inside and blasting fragments of roack away.

Subariel-processes: Processes that attack the face and top of a cliff.

Abrasion: Waves hurling sand and pebbles weakening the cliff face.

Werring/drying: soft rock expands when wet and contracts when drying out, which weakens the rock and makes it easier to erode.

corrosion: sea water is very corrosive and can slowly dissolve limestone and chaulk.

Attrition: Sand and pebbles contantly wearing away at eachother, causing them to become smaller and smoother pebbles.

Concordant - the coastline runs parallel to the British Coast.

Discordant - Goes at a right angle from to the coast.

• Soft Rock:

Erodes quickly, and thus means they can' hold themselves up, usually made from clay and an exampe is Holderness.

• Hard Rock:

Erodes slowly, and is usually made from limestone or chaulk, an example is old harry rocks.

Headland:

consists of: (a cave, an arch, a stack, a stump and wave cut platform - and can also include the origional shape of headland, undercutting and signs of weakness.) LOOK A PICTURE!

Longshore drift:

is the movement of beach material along a beach in a "zig-zag" movement, which can result in beaches being lost in seconds. The only way to prevent this is with groynes.

Slumping:

Rainfall causes cracks in the cliff, which makes the rocks become unstable causing it to collapse and create a "stepped coastline," eventually the fallen material is washed away.

Beaches:

A main feature, usually out of sand or shingle, which has been built up between high and low tide.

A spit:

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

Tombolo:

Are formed where a spit continues to grow outwards, joining the land to an offshore island.

A Bar:

Joining two headlands, behind a bar  lagoon is formed, where the water has been trapped.

Positives and nagatives:

• Hold the line:

+ Businesse and housing will be fine

- Not economically or environmentally stable.

• Advance the line:

+ Adds more land

- very costly and could floof

• Management realinement:

+ Natural and sustainable

- loss of homes and businesses

• No intervention

+ sustainable and doesn't cost

- loss of land, houses and businesses

why is there a need to protect coastal areas?

with the increased number of people, there is a higher chance of flooding and eroision so they need to be protected.

How is the coastline managed in England and Wales?

Hold the line (Defra)

managed realignment (defra)

Advance the line (defra)

Sea wall (Hard engineering)

Sends energy back to see (Splash back) and costs around £5000 per metre, however an advantage of it is that it offers the highest amount of protection and is very effective. On the other side it only lasts around 50 years and have high maintenance.

Beach replenishment (soft engineering)

Designed to stop wave energy before it reaches the hard defences and is etimated to around £5000-£200,000 per metre, they are attractive and dissipates the wave energy, however they sometimes can be swept back into the sea.

Gabion (Hard engineering)

They are wire cages filled with rocks, estimated at £5000-£50,000 and encourages upper beach stability but only has a life span of around 5-10 years.

Groyne (Hard engineering)

Designed to slow down long shore drift, around £5000 each and traps the sand which widens the beach, a disadvantage is they only have a life span of 15-20 years.

Rock armour (hard engineering)

Made from hundereds of rocks to disipate the wave energy, and cost around £100,000 - £300,000, however they have a low maintnance cost. They are a good long term source of protection but have a strong landscape impact.

Beach Recycling (soft engineering)

Shifting beach sand or shingle to other beaches, and cot around £1000-£20,000, a shrt term defence and accelerates natural recovery of fordunes, a disadvantage is that it removes sand from other beaches.

Tetrapods (hard engineering)

They dissipate the wave energy making it go around not directly hitting the beach, and costs arond £2000, and are sustainable and act as a long term defence, however they are ugly looking.

Wooden Revetment (Hard engineering)

Provide a barrier from the wave energy, around £2000-£50,000

Tetrapods (hard engineering)

They dissipate the wave energy making it go around not directly hitting the beach, and costs arond £2000, and are sustainable and act as a long term defence, however they are ugly looking.

Wooden Revetment (Hard engineering)

Provide a barrier from the wave energy, around £2000-£50,000 and are less expensive than sea wall, however have a limited life span and are un-natural looking.

Beach Reprofiling (soft engineering)

Changing the shape of the beach so it slopes to reduce the power of the waves, it can ary in price from £20-£100million, they reduce the power of the wave so won't affect hard barriers as much, however it is potentially amaging ecology.

Offshore Breakwater: (Hard engineering)

used to reduce the intensity of wave action to provide a safe harbour, estimated around £40,000 - £100,000 and is easy to repair however it looks ugly and can be displaced.

Managed retreat/realignment (soft engineering)

managed realignment is a form of soft engineering, in most cases it involves flooding/breaching the sea wall and allowing the land behind to be flooded, the price varies between destinations of millions, it has its advantages such as it reduces the amount of maintanence to sea walls, however there is a loss of land, houses and businesses due to it.