geog

• Factors influencing disaster risks according to NVE framework:

  • N: Nature of hazard
  • V: Vulnerable conditions
  • E: Exposure
• Earthquake:

  • Nature of hazard:
  • Duration of shaking:
  • Longer ground shaking leads to more damage and increased likelihood of collapse
  • Structures damaged for longer periods can result in people being trapped and more injuries/loss of lives
  • Example: 2011 Tohoku Japan Earthquake (Mw 9.9) lasted 6 minutes causing massive damage to buildings
  • Time of shaking:
  • Time of day affects response:
  • Night: less alert, less likely to evacuate quickly, leading to more injuries/loss of lives
• • Day: more alert, more likely to evacuate quickly, still resulting in injuries/loss of lives
  • Example: 1995 Kobe Japan Earthquake (Mw 6.9) occurred around 6am, resulting in 6000 lives lost
• Vulnerable conditions for earthquakes:

  • Quality of buildings and construction:
  • Vulnerable when made with poor quality materials like zinc sheets that cannot withstand shaking
  • Lack earthquake-resistant features such as reinforced steel walls
  • Example: 2010 Mw7.0 earthquake in Port-au-Prince Haiti led to the destruction of more than 90% of buildings near the epicenter and over 220,000 lives lost
  • Soil and rock properties:
  • Soil properties like liquefaction can make buildings more vulnerable to collapse
• • Example: Port-au-Prince Haiti had soft soil leading to collapsed buildings and over 220,000 lost lives
• Exposure for earthquakes:

  • Population density:
  • Higher population density means more people exposed to earthquakes, resulting in more people trapped and loss of lives
  • Example: 1995 Kobe Mw 6.9 Earthquake resulted in 6000 killed and 40,000 injured with a population density of 3000 people per km2
  • Distance from epicenter:
  • Closer proximity to the epicenter leads to more people/buildings exposed and greater disaster risks
  • Example: 2010 Mw 7.0 Earthquake in Port-au-Prince (Haiti) had the epicenter only 25km west of the city resulting in 220,000 deaths
• • Prevailing wind conditions (ashfall and tephra):
  • Larger affected areas result in higher impact on people and properties
  • Example: 1991 Mount Pinatubo, Philippines eruption spread ashfall/tephra due to fast wind speed affecting over 90,000 hectares of farmland
  • Exposure:
  • Human settlements increase exposure to hazards and disaster risks caused by eruptions
  • Despite risks, people choose to live near volcanoes for fertile soils and mining opportunities
• Volcanic Eruptions:

  • Nature of hazard:
  • Availability of surface and groundwater increases the likelihood of lahars forming, raising disaster risks and loss of lives
  • Prevailing wind conditions affect ashfall and tephra distribution, impacting people and properties
  • Vulnerable conditions:
  • Availability of surface and groundwater:
  • More availability increases the risk of lahars forming, leading to loss of lives and properties
  • Example: Mount Pinatubo, Philippines (1991) triggered by heavy rains destroying 100,000 homes
• • Example: Mount Sinabung has seen explosive eruptions since 2010, yet people still live within the 3km restricted zone for farming and mining opportunities
• • Allow people to administer basic medical care to the injured and keep them mobile for evacuation
  • Conducting evacuation drills:
  • Familiarize people with evacuation procedures/routes to reduce the likelihood of being trapped
  • Example: Nearly all 3,000 students of Kamahashi city survived the 2011 earthquake and tsunami due to disaster prevention programs like evacuation drills
• Ways to strengthen community resilience:

  • Land-use planning:
  • Control/minimize development in high-risk areas to reduce loss of lives and damage of properties
  • Use hazard maps to identify areas of risk and suggest levels of risk (high, medium, low)
  • Example: After the 1993 Japan Tsunami, residential land in coastal areas like Touni-hongo village was shifted to higher ground
  • Hazard-resistant buildings:
  • Designs include shock absorbers/dampers to absorb vibrations and diagonal cross braces to retain buildings during earthquakes
• • Example: Taipei 101 has a weighted damper to balance ground shaking
  • Monitoring/warning systems:
  • Detect seismic waves and ground deformation to make predictions and send warnings for quick evacuation
  • Example: During the 2011 Tohoku Japan Earthquake (Mw9.0), warning systems detected strong tremors and saved thousands of lives by stopping bullet trains
  • Radiating public awareness through education:
  • Provide knowledge of hazards and how to respond to them, such as temporary shelter from volcanic ash by sealing doors/windows
  • First-aid training:
• • Limited ability to respond and recover from disasters due to lack of efforts in educating and training the community, political instability, and corruption
  • Example: The 2010 earthquake in Haiti (Mw7.0) resulted in 220,000 deaths due to the lack of organization, limited medical/emergency response, and chaos/unrest leading to difficulties in recovery
• Challenges in building community resilience:

  • Extent of community's resources:
  • Lack of technological/financial resources may influence the ability of the community to reduce vulnerability
  • Developing countries often lack resources, and governments prioritize economic development over dealing with tectonic disasters
  • Example: In Bangladesh, where 30% of the population lives below the poverty line, buildings are vulnerable to earthquakes due to lack of reinforcement
  • The capability of the community to organize itself for disasters:
• Strategies to respond to disasters:
• Search and rescue efforts:

  • Important and life-saving response to a disaster
  • Involves finding and saving survivors
  • Aims to rescue the largest number of people in the shortest time
  • Skilled rescuers and specialized equipment like heat sensors reduce time taken to locate and save survivors
  • Without rescue efforts, people might die from injuries
  • Example: 2020 Aegean Sea Turkey Earthquake (Mw 7.0) had 8000 rescue/first aid teams deployed and 106 rescued
• Timely Evacuation:

  • Moving people away during hazards to safer places to reduce lives lost
  • Example: 2011 Tohoku Japan Earthquake (Mw 9.0) where nearly all 3000 students survived by immediately evacuating to higher grounds, and 2010 Mount Merapi where authorities organized more than 700 evacuation centers and saved more than 10,000 lives
• Provision of basic social and psychosocial services to affected communities
• Water:

  • Water shortage due to ground shaking or volcanic ash
  • Providing clean water can prevent dehydration and water-borne diseases
  • Example: 2010 Haiti Earthquake (Mw 7.0) in Port-au-Prince where The International Committee of the Red Cross provided water supply for 12,000 people daily
• Food:

  • Food shortage after a disaster due to shop closures or damages to crops
  • Providing food can prevent hunger
  • Example: 2017 Mount Agung Indonesia where the government and NGOs provided food for more than 75,000 evacuees
• Healthcare:

  • Disrupted due to damage to hospitals and needs support
  • Providing access to medicine, doctors, and hospitals can prevent the spread of diseases and save lives
  • Example: 2018 Fuego Guatemala where charity provided 30,000 boxes of medical supplies and 1,000 hygiene kits
• Psychosocial services:

  • Experiencing disaster leads to emotional distress
  • Survivors need counseling to cope with psychological trauma
  • Example: 2018 Palu Indonesia Earthquake (Mw 7.5) where volunteer groups focused on mental health and worked with children to help them cope with trauma
• Strategies to recover from disasters:
• Restore and improve facilities and living conditions of affected communities by constructing hazard-resistant buildings and infrastructure, retrofitting surviving buildings with hazard-resistant features, allowing residents to return to their original homes, and providing house assistance

  • Example: 2011 Tohoku Japan earthquake (Mw 9.0) displaced 500,000 people, and by 2016, the majority were rehoused with enhanced tsunami-resistant features
• Challenges in disaster management:
• Lack of domestic resources including technological and financial resources can hamper disaster response efforts, resulting in delays and lives lost

  • Example: 2010 Mw 7.0 Haiti Earthquake faced a critical shortage of ambulances and heavy machinery to remove rubble from collapsed buildings, leading rescue teams to spend many hours removing rubble manually
• Challenge in engaging relevant stakeholders to collaborate and integrate disaster management strategies into their practices due to disagreements, lack of awareness, and high costs

  • Example: In the Philippines, only 10-20% of buildings are insured against earthquakes due to high insurance costs