different coastal enviroments
-different rock types and the processes of eriosion that are prone to these areas.-cliffs-arches-stacks-sheltered inlets- natural harbours.
different physical features encourage different types of development-
-dramatic scenery- jarassic coastline ( world heritage site)
-natural harbour- inporting and exporting easy.
-beaches in areas with equable( warm) climates.
-high bio diversity
increased develpment causes coastal population gro
-there are physical factors including accsessibility, fertile soil, equable climate, scenery and high biodiversity which can lead to an increase in the fishing and tourism indistry.
-incresase in ^ means an increase in pop as people move for incrreased job opps.
-flat land makes it easy to develope and build onto- encouraging people to the area.
dubai- less the 20% of the people who live in dubai are native- due to population growth.
-florida 80% of people live on the coast.
felidwork and research factors that affect populat
-looking at historical documents and maps to see how land use has changed.
-to find out population numbers you can look at census data.
-local newspapers for any new development projects
-holiday brochers to see what attracts people to the area.
-land use survey to look at visible evidence of economic development.
-survey to find peoples reasons for moving to the area.
coastal development disort land use model
-Coastal development creates patterns of land use zoning- there are a number of common charactoristcs of a UK seaside location such as....
-SHAPE- limits growth with the main road on the sea front.
-ACCOMIDATION- hotels with sea views cheaper accomidation is away from the sea front were as expencive has se views.
-OPEN SPACES- including parks or pleasure gardens they were set aside when land prices were lower.
-ENTERTAINMENT- piers and archades.
coastal development has lead to planning control- rate increases and so does development.
coastal development can cause conflict with coasta
different people have different ideas on how developmet should take place on the coast- stake holders. these is often conflic between the stake holders for example-
-TOURISM- it will bring job ops and increased spending however it can increase noise , light and air pollution. It can have and enviromental impact with the disruption of land for new roads.
-OVERFISHING-can bring jobs and money but over fishing can lead to not enough fish being left.
-AQUA CULTURE- people wanting cheap fish has lead to fish farms this leads to conflict between producers and enviromentalists. high levels of fish can lead to a decrease in oxygen levels in the water and kill other fish as a result.
-INDUSTRIALISATION- as ports have expanded because of growth in indistry , coastal ecosystems are under threat. such as salt marches which want to be developed but many are SSSI.
tools to assess conflic and evaluate development-
-ENVIRONMENTAL IMPACT ASSESSMENT- this helps to identify the enviromental consoquences of a development project.
-COST BENIFIT ANALYSIS- this process allows the cost and benifit of any development to be examined to see if it should go ahead.
-VALUE ANALYSIS- this identifies different view points of stakeholders in the project.
fieldwork- enviromental value survey- recreastinal value- biodiversity survey.
research- planning aplications - envirometnal value- assess the impact of fishinhg.
IMPUTS-river sediment, cliff sediment and transported sediment.
PROCESSES- wave action, tidal movement, erosion, transportation, depostiation.
OUTPUTS- sediment washed out to sea or deposited along the coast line.
waves are responsible for erosion and depositation
- waves are created by wind-wind blowing over the sea give the water a cercular motion.
-this effects the fetch- which is the maximum distance the of the sea the wind has blown over to create the wave.
-as the wave is about the break friction with the sea bed slows it down.
TIDES AFFECTS WHERE A WAVE BREAKS.
At high tide they break higher up the shore
sub arial weathering along the coastline.
-sub arial weathering describes processes that are not linked to the sea- freeze thore weathering and salt weathering - this weakens the cliffs.
-through flow- ( flow of water through the cliffs) caused by heavey rain can make the cliffs unstable and increase the likelyhood of mass movement.
-mass movement- is the movement of matireal down hill due to gravity, this includes landslides-mass movement- slumping.
five main ways for waves to erode the coastline-
-abrasion- bits of rock transported by waves grind against rock- smooth surface.
-hydrolic action-air in rocks is compressed and this breaks off rock pieces.
-quarrying-the energy of the waves against the cliffs destroys bits of rock.
-corrosion-soluble rock get disolved in the sea- limestone and chalk
-attrition-bits of rock in the water smash against each other and get smaller.
rate of erotion
this depends on a number of factors-
THE WIDTH OF THE BEACH-the distance between high and low tide marks, beaches slow down waves and reduce there erosion power.
THE BREAKING POINT OF THE WAVES- a wave that breaks directily at a cliff transfers the most energy to the cliff face.
THE ASPECT- if the coastline faces wind and wave direction erosion will be faster.
THE FETCH OF THE WAVES-longer fetch means more erosion.
ROCK TYPE-soft rock more erosion.
natural physical causes of coastal flooding
LOW PRESSURE IN THE ATMASPHERIC SYSTEM
STRON ONSHORE WINDS
TIDLE CURRENTS- STORM SURGES
COMBINATION OF ALL FACTORS ABOVE
HUMAN ACTIVITY THAT CAUSES FLOODING-
MANAGMENT OF RIVER SYSTEM- some reduce sediment being trapped thus destorying natural defences such as salt marches providing less protection from high tides and storm surges.
MANAGEMENT OF COASTAL SYSTEM- some alter sediment movement reducing the amount of protective beach matireals.
BUILDING ON COASTAL LOW LANDS-this isncreases the impact of any floods as the natural defence has been ruined.
RECLAIMING OF COASTAL LOW LANDS- reclaiming it and draining it makes the land shrink and become low lying.
coastal flooding is more likely to increase due to sea level rise- 4-5 meters by 2100.
sea level changes-
they can either be..
EUSTATIC- caused bu the changes in the volume of water or shape of ocean basin.
ISOSTATIC- sea levels change is caused by vertical movments of the land relitive to the sea.
Sea level change can have a number of impacts-
-more frequant and survear costal flooding
-submerged low lying land
-changes in coastline.
the holderness coast
location- east yourkshire
-fastest eroding coastline in europe.- 1.8 meters per year
-soft rock type- boulder clay
-narrow beaches mean less resistance against the waves erotion power
-powerful waves with a long fetch
-propity prices have dropped as the risk from erotion has increased
-lost 30 villages since roman times
-visitor numbers have decreassed by 30% since 1998
-800,000km2 of farmland is lost per year.
options for coastal mangement
HOLD THE LINE- maintain the exsisting coastal defences
ADVANCE THE LINE- build new coastal defences out to sea
DO NOTHING- build no defences and deal with flooding when it comes.
RETREAT THE LINE- build nothing but move people away from the coast.
coastal defences- hard engenirering and soft
SEA WALL- expenceive
GABIONS- cheap and ugly
RIPRAP- farily cheap- don't do well in big storms
GROYNES- fairly cheap- can shift in storms
LAND USE MANAGMENT
CREATING MARSH LAND
SOFT ENGINEERING IS MORE SUSTANIBLE THEN HARD.
-disrupts natural processes
-needs less maintainance
soft engeniring is more sustanible as it has lower enviromental impacts and social costs.
why defences need to be sustanible
-rise in sea levels puts more people at risk
-sustanible is better
-fits better with shore line managment plan SMP
hard engeniring in the holderness-
-4.7km of sea wall
-2 rock groynes
fieldwork and reasurch into coastal managment schemes-
-rates of erotion before and after defences are put in place.
-flood risk before and after
-local news papers
-questionaiires to find out how the scheme has effected people