AS - Tectonics and Coasts

• Haiti Earthquake

  Year: 2010

  Plate Boundary: Conservative

  Plates: North American and Caribbean

  Epicentre: 25km SW of Port-au-Prince

  Richter Scale: 7.0
• Why is Haiti susceptible to hazards?


  Multiple hazard zone

  Limited development of infrastructure

  Lack of health services

  Poor ability to cope

  Low resilience and recovery rate
• Primary effects of Haiti


  …

  • Ground Shaking
  • 70% buildings destroyed
  • 65km rupture
  • Communications lost
  • Road collapse
  • 4,000 amputees
• Secondary effects of Haiti


  …

  • Food, water and medicine shortages
  • 52 aftershocks
  • 230,000 dead
  • 500,000+ disease cases
  • 1.5 million homeless
• Long term responses of Haiti

  …

  • 20% jobs disappeared
  • Buildings were surveyed and colour tagged to meet stricter codes
  • Community projects (too few to make an impact)
  • 95% children returned to school
  • 810,000 ppl still in camps 1yr later
• Sendai Earthquake


  Date: 11th March 2011

  Plate Boundary: Destructive

  Plates: Eurasian, Philippine, Pacific, Okhotsk

  Epicentre: 100km SE of Sendai

  Richter Scale: 9.0
• Primary effects of Sendai


  …

  • Ground Shaking
  • 25 million tonnes of debris
  • 144,300 buildings damaged
  • 45,700 destroyed
  • Communications lost
  • 1.5 million homes without water and electricity
  • Soil liquefaction - 400km vertical stretch
• Secondary effects of Sendai


  …

  • Tsunami (40m high)
  • 200,000+ ppl evacuated from Fuskushima nuclear plant
  • 15,000 dead
  • 6,000 injured
  • Disease
  • 452,000 in evacuation facilities
• Immediate responses of Sendai

  …

  • 452,000 ppl in temporary accommodation
  • JSDF - Japanese Self Defense Force. Search and rescue group that got there in 10 minutes
  • Japanese Red Cross opened aid funds within a couple hours
• Long term responses of Sendai

  …

  • GDP went down 5% (300 billion)
  • Fuskushima still contaminated with radiation
  • Banned exports due to radiation (rice, beef)
• Iceland Volcano

  Year: 2010

  Plate Boundary: Constructive

  Plates: North American and Eurasian
• Primary effects of Iceland


  …

  • Glacial melting
  • 9m high plumes of volcanic ash
  • 15 lava fountains at 150m high
  • Volcanic gases - CO2, SO2, CO
  • Lava flows
  • Rapid pyroclastic flow
• Secondary effects of Iceland

  …

  • No deaths
  • Lahars
  • Glacial flooding
  • Mass evacuation
  • Poor air quality due to ash cloud
• Immediate responses of Iceland

  …

  • Aid
  • 100,000 flights cancelled in the following week affecting 7 million passengers
  • Camps set up
• Swiss cheese model

  
• Pressure and Release model (PAR)

  
• Park‘s disaster curve

  
• Risk poverty nexus

  
• Hazard profiles

  
• Degg's model

  
• Earthquake waves

  
• Geology of Holderness Coast


  …

  • Mostly made from boulder clay but also fine clay, sand and boulders
  • Flamborough head made from hard chalk
  • Average rate of erosion: 2.26m
  • Differential rates of erosion give coastline distinctive shape
• Fetch of Holderness Coast

  …

  • Relatively small (500-800m)
  • Powerful, destructive waves from strong Atlantic currents
  • Intense storms
  • Relatively deep sea floor
  • Small drainage basin
• Hornsea and Mappleton

  …

  • Regional economic centre with 8500 ppl
  • Important historic sites and Hornsea Mere (SSSI)
  • Hold the line policy
  • 1990’s: had 2 rock groynes, rip-rap and cliff regrading.
  • No active intervention - 400m of land could be lost to erosion by 2105
  • By 2105, a small village of 50 properties could be cut off from a minor road west of the village making it a high risk location.
• Blackwater Estuary, Essex


  …

  • Tidal salt marsh and low lying farmland
  • Coastal defences aren’t sustainable due to coastal squeeze. Managed retreat has occurred (area allowed to be flooded)
  • 2000: Essex wildlife trust purchased Abbots Hall Farm on Blackwater Estuary. 4000 hectare scheme implemented to allow new salt marshes to form
  • PRO: High costs of hold the line avoided
  • PRO: Reduced flood risk
  • PRO: Additional income from ecotourism and wildfire watching
  • Shows that all stakeholders can be happy even when radical plans are adopted
• Flooding in Australia


  Population: 25.7 million

  • Most ppl and infrastructure is on the coastline
  • $67 billion road and rail risk
  • $72 billion homes at risk
  • $226 billion worth of infrastructure at risk at a sea level rise of 1.1 metres
• Flooding in Philippines


  Population: 114 million

  • $6.5 billion a year predicted damages due to sea level rise
  • Rate of sea level rise 5.8mm over annual average
  • High poverty and economically vulnerable
  • Damage to mangroves, corals and seagrass have reduced the ability to protect from flooding
• Maldives


  Population: 400,000

  • Low lying islands with average ground elevation 1.5m above sea level
  • Currently use sandbags as defences but sea level rise is increasing
  • Flooding would cause jobs to disappear causing migration to other countries
  • Other countries aren’t willing to accept so many people
• Coastlines

  
• Longshore drift

  
• Rockfall

  
• Slide

  
• Rotational Slumping

  
• Mudflow

  
• Constructive waves

  
• Destructive waves