Geosciences, Lecture 3

Hazard Preparedness

• Protocols and procedures are essential planning elements for communities to prepare for natural disasters.

• Hazard-mitigation efforts are implemented to decrease the consequences of disasters.

  • Examples include:

  • Buoys that detect and broadcast tsunami warnings.

  • Signage that directs individuals to tornado shelters.

• Communities must first establish their hazard exposure to identify risks.

• Following this assessment, communities create:

  • Zoning laws

  • Building codes

  • Evacuation protocols

  • Example: Tornado warning sirens and informational signage as immediate responses.

Building Codes and Design Considerations

• In flood-prone areas, building codes may require:

  • Homes to be constructed on stilts or pilings to mitigate flood damage.

  • Understanding of sea levels during a storm vs. normal sea levels.

Costs of Disasters

• Globally, the costs of disasters totaled over $1 trillion between 1995 and 2015.

• In low-income areas, disaster costs often fall on individuals, leading to bankruptcies when costs exceed their ability to pay.

• In wealthier areas, individuals typically rely on insurance policies to cover financial losses.

  • Insurance policies are essential for mitigating disaster-related financial impact.

  • Actuaries play a key role by calculating risk and establishing insurance rates.

Disaster Insurance

• Insurance companies mitigate their risk by selling a large volume of policies, as disasters are infrequent thus keeping companies solvent.

• Companies also engage in reinsurance—buying insurance for themselves to cover potentially high claims costs.

• Homeowner's insurance polices generally cover:

  • Fire

  • Wind

  • Theft

• The National Flood Insurance Program provides backing for flood insurance policies.

Review Questions

• Examine provided figures regarding worldwide disaster costs to analyze key statements:

  • (a) Disaster costs are generally increasing.

  • (b) Costs exceeded $300 billion during specific years.

  • (c) Insurance coverage is less than half of total disaster costs.

  • (d) The figures illustrate all above analyses.

Energy Sources for Natural Disasters

• All natural hazards are associated with energy transformations that complicate human responses.

  • Key sources of energy include:

  • Motion (kinetic energy)

    • Examples: Asteroid impacts

  • Gravity (gravitational potential energy)

    • Examples: Landslides, sinkholes, tsunamis

  • Earth's internal energy (thermal energy)

    • Causes volcanic eruptions and earthquakes (related to plate tectonics)

  • The Sun

    • Drives hurricanes, tornadoes, and lightning.

Energy Formulas

• Kinetic Energy Formula:

  • $K.E. = \frac{1}{2} M V^2$

  • Where:

    • M = Mass (kg)

    • V = Velocity (m/s)

• Gravitational Potential Energy Formula:

  • $G.P.E. = Mgh$

  • Where:

    • M = Mass (kg)

    • g = Acceleration due to gravity (9.81 m/s²)

    • h = Height (m)

Examples of Energy in Natural Disasters

• Example of gravitational potential energy in action:

  • Debris Flows occurring on Aconcagua, Argentina, characterized by steep slopes and minimal vegetation, common around volcanoes.

Energy Transformations

• Each form of energy can be transformed into different forms of energy, leading to various natural disasters—the interconnected nature of these energies enhances the complexity of hazards faced by societies.

Activities and Tools

• Fun Fridays for class activities based on main concepts learned.

• National Risk Index:

  • Examine the link to explore NRI data and engage with peer discussions.

• Hazard Cards for various disasters (wildfires, tsunamis, tornadoes, inland flooding, coastal flooding, hurricanes, earthquakes) are available for investigation, each with maps reflecting risk indices.

  • Students to explore distribution patterns of hazards using National Risk Index maps.