coasts

• the Maldives -

  • 97% of inhabited islands are experiencing erosion - and as sea levels rise an increased risk of flooding
  • coastal management by local government not sustainable:
  • isolated islands are ignored as most money is spent on capital city (Male)
  • sustainable management of traditional income sources (eg fishing) are overlooked in favour of protecting tourist and urban developments
• the Maldives: NGO intervention -

  • NGO's have encouraged sustainable living and educated locals to change situation - more successful than government cause theyve involved and centred efforts around locals
  • mangroves for future (MMF) is educating communities about importance of coastal mangroves as a defence against erosion and flooding - reducing deforestation
  • global environment facility (GEF) provided small grants to locals on the islands in order for them to help develop sustainable and organic farming
• netherlands deltawerken project -

  • hard engineering project which began following the 1953 storm surge
  • 1800 people died as well as flooding of 10% of the Netherlands farmland
  • 40,000 buildings were damaged and a further 10,000 destroyed
• netherlands deltawerken project: scheme -

  • series of dams and gates constructed along rivers to control the flow of water during a storm surge
  • aims to reduce the length of the coastline exposed to the sea whilst maintaining safe access to the North Sea for shipping
• netherlands deltawerken project: sustainability and longevity -

  • cost of project was 5 billion - due to sea level rise dutch will need to spend more than 1 billion annually to maintain and improve defences
  • allowed 4 million people to live below normal sea level - easing population growth
  • dams have allowed for new roads and transport connections - drastically reduce journey times and reduce isolation for settlements
  • number of nature reserves lost during construction - some replaced during project
• tuvalu -

  • low lying pacific island - becoming increasing vunervale eustatic sea level rise continues
  • most areas only 1-2m above sea level - highest point 4.5m above
  • population have had to mitigate to the changing coastal environment or forced to migrate to New Zealand
• tuvalu: problems and mitigation solutions -

  • more tropical cyclones are occurring due to increase in sea temps - residents must construct cyclone shelters to avoid injury
  • flooding of low-lying settlements has resulted in the drowning of cattle - farmers forced to move further inland - may consider importing food to avoid hunger
  • salt water encroachment has led to crop failures and loss of local water sources - residents grow staple crops in concrete plots and must travel further inland to access a freshwater supply to drink from and water their crops
• tuvalu: migration -

  • come cannot afford to mitigate or are fed up of losing cattle, crops and economic assets
  • growing number of environmental refugees from Tuvalu who must love in New Zealand to survive
  • can result in a better standard of living but cultural tensions can arise between the migrants and locals
• US east coast barrier islands: characteristics -

  • east coast is dominated by barrier islands - found from Florida in south all the way up to Connecticut in north
  • made of sand - 23 shifting barrier islands which each create lagoons behind them
• US east coast barrier islands: conservation -

  • barrier islands are form of defence - they dissipate wave energy so waves hitting land are less destructive - east coast is repeatedly hit by hurricanes so are natural defence against storm surges
  • most islands open for low-impact tourism activities - many restrictions to protect nature
  • no permanent residence is permitted - previous beach resort and settlements have been washed away due to shifting nature of islands
• holderness coastline -

  • north-east of England
  • retreats at rate of 1-2m per year
• holderness coastline: why is it retreating so rapidly -

  • exposed to strong prevailing winds from north-east with a small fetch of 500-800km
  • longshore drift moves material south along the coastline where cliffs are poorly protected against wave attack
  • cliffs are made of soft boulder clay - structurally weak and little resistance to erosion
  • not much sand to stop waves reaching cliff face at high tide
  • low pressure weather systems and winter storms often intense producing strong winds and rain
• holderness coastline: management -

  • mappleton - could become 30th village lost to the sea
  • road running through it links towns along the coastline and would've been lost to coastal erosion if protection measures weren't put into place - coast of coastal defence less than cost of building new road
  • blocks of granite brought in and placed along the cliff base + 2 rock groins were put into place to trap sediment moving because of longshore drift
• cornwall -

  • rocky coastline can withstand frequent winter storms without suffering rapid erosion due to rock type:
  • igneous rocks (basalt and granite)
  • older compacted sedimentary rocks (old red sandstone)
  • metamorphic rocks (slates and schists)
• Bangladesh: why is it vulnerable -

  • most densely populated country in the world
  • 46% of population live less than 10m above sea level
  • lies on flood plains of 3 major rivers - eg Ganges
  • lies below Himalayas so vulnerable to flooding due to melting ice caps
  • contains mostly unconsolidated sediment which is easily erodible
  • deforestation is increasing which removes coastal mangroves which essentially is removing a coastal defence - increases flood risk
  • experienced intense rainfall due to 40% of all global cyclones occurring here
• Bangladesh: cyclone Sidr -

  • struck south west coast of Bangladesh
  • tidal waves up to 5m high breached coastal and river embankments
  • low-lying areas were flooded causing significant damage to housing, roads, bridges and other infrastructure
  • electricity and communication lines damaged
  • drinking water contaminated by debris and many sources inundated with saline water from tidal surges
  • 2.3 million households affected
  • estimated 3400 deaths
  • US$1.7 billion worth of damage
• hornea and mappleton -

  • concrete walls - wave hits the wall then travels along it in a corkscrew manner - curve of the wall takes the energy out of the wave
  • rock revetments, rock defences - particularly at Hornsea
  • 1991 - protect mappleton - coastal management scheme costing 2 million introduced involving 2 types of hard engineering - rock armour along base of cliff and building 2 rock groynes - no longer at risk from erosion
  • rock groynes - stopped beach material being moved south from mappleton along the coast - increases erosion south of mappleton
• Kiribati

  sea level rise
• uk storm surge

  floods