2 Coasts Flashcards
Formation of a spit 1) why does longshore drift hit the beach at an angle?
It hits the beach at an angle due to wind direction.
Formation of a spit 1) what angle does swash hit the beach?
At a 45¿ angle, this is due to wind direction.
Formation of a spit 2) What angle does backwash move back to sea?
At an angle of 90¿ (straight line from the beach).
Formation of a spit 2) Why does the backwash move straight back away from the beach?
Due to the pull of gravity.
Formation of a spit 3) How is sediment moved down the beach?
The process the longshore drift is repeated over and over again.
Formation of a spit 4) When there is a change in the shape of the coastline what happens?
Sediment is deposited is the same direction a sthe original coastline.
Formation of a spit 5)Why is a spit curved?
A spit is usually curved at the seaward end due to wave action and ocean currents.
What is a bar?
A bar is formed when a spit extends across an opening and connects two areas of coastlien.
What is a tombola?
Where a spit is extended until it joins an island.
Name an example of a spit.
Spurn Point
Who is responsible for coastal erosion?
Defra
What is Defra?
Department for environment, food and rural affairs
What is a sediment cell?
The coastline has been divided up into 11 areas to help make areas of the coast more manageable.
What is a sub cell?
A sub cell is where sediment cells have been divided up even further to help with SMP.
What is SMP?
SMP is a shoreline management plan. This is a document that sets out plans for the management of a length of coast.
Defra have four management strategies. What are they?
Hold the line, advance the line, managed realingment and no intervention.
What does hold the line mean?
To hold the line is to maintain the existing coastline by building defences.
What does advance the line mean?
To advance the line is to build new defences infront of the existing defences.
What does managed realingment mean?
Managed realingment means to allow the land the flood and to construct a new line of defence inland.
What does no intervention mean?
No intervention means to allow natural processes to shape the land.
What is hard engineering?
Hard engineering controls the power of the sea by building barroers between the alnd and the sea e.g. seawalls.
Give some examples of hard engineering.
Sea wall, groyne, rock armour, cliff drainage.
What are the negatives of hard engineering?
Expensive, unsightly, does not match the natural landscape.
What are the benefits of hard engineering
Very effective, longlasting and can be multi-puroose e.g. a sea wall can have a promenade ontop.
Give an example of where hard engineering is used.
Seawall, Poole Bay near Bournemouth.
What is soft engineering?
Coastal protection which works in keeping with nature. E.g. beach replenishment.
Give some examples of soft engineering.
Beach replenishment- putting more sand on the beach to widen it. Managed realingment which allows the sea to flood till it reaches a natural barrier of higher land. Offshore reefs (plants) out to sea which help break up the power of the waves.
What are the negatives of soft engineering?
Doesn’t last as long at hard engineering. Sometimes not powerful enough to protect large built up areas.
What are the benefits of soft engineering
Looks natural, can be cheaper than hard engineering.
Give an example of where soft engineering is used.
Beach replenishment at Poole Bay near Bournemouth.
What coastal management has been done at Sea Palling?
Seawall, boulders placed in front of sea wall, beach replenishment and four offshore reefs.
Where is Sea Palling?
North-east Norfolk
What conflict has been caused by coastal management in Norfolk?
Local residents are unhappy with the councils decision to do nothing. They have launched the ‘buy a rock for Happisburgh’ campaign which is raising money for hard engineering defences.
Where is Happisburgh?
North-east Norfolk
What are the causes of cliff erosion at Happisburgh?
Soft clay rock, large fetch across the North Sea, storms.
Why are coral reefs fragile?
Easily damaged by pollution because ethey are found in shallow ocean water. When touched by divers they can die.
Where do you get coral reefs?
only found in tropical areas where there are warm shallow oceans.
What are coral reefs?
Coral reefs are formed by colonies of tiny animals (polyps). When they die they leave behind a skeleton made up of calcium carbonate.
What is the SMMA?
Soufriere Marine Management Area in St. Lucia
Why is there conflict between coastal uses?
Different groups want prioritye.g locals will want to fish but this will disturb tourist activities.
Give an example of managed retreat.
Wallasea, essex.
Why is managed retreat a good thing at Wallasea?
it created 155 hectares of mudflats and salt marshes, which is a habitats for birds. Salt marshes provide a natural sea defence. Reduces the risk of flooding further inland.
How will climate change affect coastal areas?
Increased sea level rise and stroms.
half a metre rise in sea levels could cause how much damage (Ï)?
Ï30 billion
