coastal landscapes Flashcards
where is the case study?
walton on the naze in essex
what type of rock does walton on the naze have?
london clay - soft rock
protected needed for?
12, 000 inhabitants & 100, 000 visitors
what and when was the hard engineering used?
groynes and sea walk built in 1977
what and when was soft engineering used?
beach replenishment in 1999 with cliff regarding
how has coastal recession effected Happisburgh?
25 homes lost, gone down in value
effects of coastal recession in Mapleton?
farmland lost - 2M per year
in dawlish?
tourism effected
how could you prevent coastal flooding?
bangladesh - megaphone & flag warnings
USA- evacuation routes and flood prof homes on stilts
what is the definition of intertidal zone?
the area above water at low tide and underwater at high tide
what are the characteristics of a constructive wave?
less powerful and stronger swosh than backwash
characteristics of a destructive wave?
backwash stronger than swosh
high energy and short wavelength
how does crystallisation work?
tide goes in and out, water fills crack in rock, sun heats water and evaporates, salt is left over
how are headland and bays formed?
hydraulic action & abrasion erode the hard rock
how are caves produced?
crack forms in the rock due to hydraulic action, crack gets bigger and form a cave.
how is an arch formed?
cave is present and the water erodes the headlands leaving an arch
how is a stack formed?
the water erodes bottom of the arch and the rock falls
how is a stump formed?
finally the rock gets reformed down until a small piece of rock is left - stump
what is longshore drift?
transports materials along beach. goes in direction of the wind then go straight back into the sea due to gravity
how does longshore drift create a spit?
movement of sediment goes past the coast & rocks are deposited into ground - forms a spit with a marsh behind it
what 4 things speed up cliff recession?
bigger waves from the wind
bigger fetch
vertical layered rocks erode faster than horizontal
type of rock
3 ways to predict a coastal flood?
spring tide - much higher due to sun & moon
deeper water
strong winds
4 ways a HIC can reduce effects of coastal flooding by building design?
house raised
steel constructions
pannels over windows
make ground floor storage rooms
how could LICs do this?
raised area made out of concrete that fits 3000 people
what are 3 types of hard engineering?
groynes
sea walls
off shore reefs
what are the advantages and disadvantages of groynes?
pro - stops sand moving - bigger beach- waves further away
cons - very expensive and lots of maintenance needed
what are the advantages and disadvantages of sea walls?
pros - deflects waves energy back out to sea, no maintenance needed
cons- expensive, ugly
what are the advantages and disadvantages of offshore reefs?
piles of boulders to absorb energy, attractive
cons- expensive & lots of maintenance
what are 2 soft engineering methods?
gabions and cliff regarding?
what are the advantages and disadvantages of gabions?
pros- not a lot maintenance needed, cheap
cons- ugly, unpopular
what are the advantages and disadvantages of cliff regarding?
pros - reduces angle of cliff, attractive
cons- doesn’t completely stop erosion
