case studies

• Mt Merapi


  Composite volcano
• Short-term effects of Mt Merapi eruption

  • Primary: Volcanic bombs and heat clouds, with temperatures up to 800°C, spread over a distance of 10 km
  • Secondary: Ash clouds caused major disruption to aviation across the region
• Long-term effects of Mt Merapi eruption


  • Positive: 210 evacuation centres were set up in schools, churches, stadiums and government offices
  • Negative: -
• Holderness coast

  • Europe's fastest eroding coast
  • Medium prediction for sea level rise is 30 cm in the next 50 years
• Spurn Head

  • 5km long spit that grows 10cm yearly
  • Protected as an SSSI
  • Made of boulder clay and chalk, easily erodible material
  • Threatened by powerful destructive waves from long fetch + winter storm surges
• Withernsea


  • Straight sea wall built in 1875, collapsed over time
  • Replaced by a curved sea wall in the 1990s at a cost of £6.3 million, £5000 per metre
  • Negative impacts: Waves are noisier, promenade is smaller, view from seafront is restricted, rock armour is considered ugly
• Hornsea


  • Concrete sea wall
  • Groynes repaired and built at a cost of £5.2m
  • Rock armour
  • Rapid wave attacks have eroded the beach by 4m per year since the 1990s
• Mappleton


  • £2.9 million of damage a year before management was put in place
  • 450 metres of sea defences including rock groynes, rock armour costing £2million, and cliff stabilisation
  • Positive impacts: Waves no longer reach the base of the cliffs, cliff stabilisation has managed threats of mass movement, B1242 road is safe
  • Negative impacts: Not visually appealing, expensive, restricted access to beach, terminal groyne syndrome and sediment starvation 3km downdrift
• Easington


  • Scheme protects gas terminal, not the village
  • Rock armour costing £4.5million, groynes, revetments
• Why does Holderness need to be protected? (Social, economic, environmental)
• Why is the erosion so bad on the Holderness coast?
• Lulworth Cove


  • Formed after an Ice Age, where a river running to sea became swollen with glacier meltwater
  • Erosion of the river banks and marine erosion at the mouth widens the river
  • Now the sea can access soft rock behind the cliff face, and erosion accelerates to form a cove
• Old Harry Rocks


  • Chalk formations of stack and stump
  • Created by hydraulic action
  • Chemical weathering and erosion are wearing them down
  • Biological weathering caused by the vegetation on the top of the headland is also breaking up the rock
• Kiribati


  • The main island, South Tarawa, has a population of over 50,000
  • Most areas are under 1m below sea level
  • No current coastal protection
  • Sea levels are rising by 12mm, 4 times higher than global average
  • Most places are predicted to disappear below sea levels in the next 50 years
  • Rising sea levels results in salinization → contamination
  • Shift in weather patterns could push South Tarawa into the hurricane belt
• Mitigation strategies for Kiribati


  • Encouraging people to grow and eat local foods so migration from other islands to South Tarawa is limited
  • President purchased 20mh of land in Fiji for agriculture and fish farming projects
• Options available to residents of Kiribati

  • Mitigation with dignity policy → people are allowed to apply for jobs in neighbouring countries
  • People can move as environmental refugees
• Players in international decision making for Kiribati

  • IPCC, UN, USA, EU, China, Australia, New Zealand
• Players' Involvement


  • Paris climate agreement
  • Carbon reduction targets
  • Compensation/aid
  • New Zealand and Australia have relocation schemes for migrants affected by climate change
  • Australia sends sand to replenish eroded beaches
• Reason for players' involvement in Kiribati
• Bangladesh


  • Very densely populated: population of 169 million
  • 46% of population lives less than 10m above sea level
  • Will see an 11% loss of land to sea level rise alone
  • Sunk by 1.5 metres in 50 years
  • Water desalination and agriculture are at risk of sea water contamination
  • Fishing jobs account for 3.8% of the GDP of the country and are the most affected by sea level rise
• Human factors exacerbating the situation in Bangladesh


  • Subsidence: Clearing and drainage of more than 50 large islands in the River delta, deforested for the growing population
  • Removing vegetation: Half of all global mangroves have been removed, mangroves are a natural flood defence and 71% of Bangladesh's mangrove forested coastline is retreating by as much as 200 metres per year
  • In the 1960s-70s large embankments were created to protect these areas but this has stopped natural deposition
• Physical factors exacerbating the situation in Bangladesh


  • Bangladesh is on the floodplains of three major rivers – the Brahmaputra, Meghna and Ganges which converge at Bangladesh
  • Ice melt from the Himalayas causes flooding
• Odisha, Integrated Coastal Zone Management (ICZM)


  • Aim: Establish sustainable economic and social activity, resolve challenges and conflict, protect coastal environment
  • Stakeholders: Water Resource Department, Greenspace India, Odisha Tourism Development Corporation
  • Issues identified: Coastal erosion and processes, vulnerability to disaster - cyclones, pollution and environmental quality management, biodiversity conservation
• Flood defence in Bangladesh


  • 71% of Bangladesh's mangrove forested coastline is retreating by as much as 200 metres per year
  • Caused by erosion and rising sea level
• Flood defence in Bangladesh


  1. In the 1960s-70s large embankments were created to protect these areas

  2. This has stopped natural deposition
• Physical factors exacerbating the flood situation in Bangladesh


  • Bangladesh is on the floodplains of three major rivers – the Brahmaputra, Meghna and Ganges which converge at Bangladesh
  • Ice melt from the Himalayas causes flooding
• Integrated Coastal Zone Management (ICZM) in Odisha


  Aim is to establish sustainable economic and social activity, resolve challenges and conflict, and protect the coastal environment
• Stakeholders in Odisha's ICZM


  • Water Resource Department
  • Greenspace India
  • Odisha Tourism Development Corporation
• Issues identified in Odisha's ICZM


  • Coastal erosion and processes
  • Vulnerability to disaster - cyclones
  • Pollution and environmental quality management
  • Biodiversity Conservation
• Stakeholders in Odisha's ICZM


  • Residents and local community
  • Local government
  • Fishing community
  • Odisha Tourism Development Corp.
  • Ecologists and wildlife specialists
  • Odisha State Pollution Control Board
• Cyclone Sidr


  Category 4 storm that caused storm surges, high winds, and flooding in Bangladesh in 2007
• Cyclone Sidr struck the Bay of Bengal


  15 November 2007
• Cyclone Sidr


  • Wind Speeds: 223 km/hr
  • Storm Surge Height: 4.5m-6.0m
  • Initial Death toll: 3363+ (rose to 1000+)
  • Cause: Change in sea level caused by depressions and tropical cyclones
• Impacts of Cyclone Sidr


  • Social impacts: 1.5 million damaged houses
  • Economic impacts: $1.7b damage
  • Environmental impacts: Fresh water contamination
• Nepal Earthquake


  25 April 2015
• Nepal Earthquake 2015


  • Magnitude: 7.8
  • Depth: 15km, Shallow
  • Cause: Indian and Eurasian plate destructive collision boundary
  • Epicentre was close to Nepal's capital Kathmandu (80km from capital)

  
• Impacts of Nepal Earthquake 2015


  • Social impacts: 9,000 people died, 21,000 were injured, 3 million were displaced
  • Economic impacts: More than half a million houses collapsed or were seriously damaged, Infrastructure was destroyed, Damage to agricultural land, Decrease in tourism, Loss of US$5 billion from Nepal's economy (about 25% of Nepal's GDP)
• Physical factors that exacerbated the Nepal Earthquake

  • Earthquake was shallow – depth of 15km
  • Epicentre was close to Nepal's capital Kathmandu (80km from capital)
  • The Himalayas is geologically young meaning more landslides
  • Nepal is mountainous and a multiple hazard zone, triggering landslides
  • Many large aftershocks caused further damage and deaths

  
• Human factors that exacerbated the Nepal Earthquake


  • The local earthquake science is out of date
  • High population density in Kathmandu – 13,000 per km2
  • Nepal has a poor (vulnerable) population
  • Many homes are owner-built and do not follow building codes
  • Nepal has weak infrastructure – roads, bridges and safe water supplies
  • The emergency services were unable to cope
• There is a low population density in rural areas which is where the worst damage occurred from the Nepal Earthquake