5 - Hazards Flashcards
1 - When does a natural hazard become a natural disaster?
1 - When there is a loss of life and or destruction of the built environment or disruption to human activities
2 - What factors determine the impact of a hazard?
2 - Its magnitude and duration.
- Ranges by a term of environmental, social and economic factors such as mitigation, experience, perception, reparation, physical setting and many more.
3- What factors influence hazard perception?
3 - Socio-economic status
- Education
- Employment
- Culture
- Past experience
- Values
4 - What is meant by hazard management?
4 - Response
- Resilience
- Predication
- Protection
- Prevention
5 - List the difference between oceanic and continental crust
5 - Oceanic crust is relatively thin [5km average]
- Oceanic crust is composed of basalt rock
- Continental crust is mainly granite
- Continental crust is less dense [average 30 to 100km deep]
6 - Draw a simple diagram to show the process and landform at an oceanic-oceanic destructive plate margin and a continental plate margin.
6 - Refer to book page 226
7 - Outline the difference between volcanic activity at constructive and destructive plate margins
7 - At constructive plate margins magma flows to the surface under reduced pressure; lava tephra and hot gases are part of the eruption.
- Lava is is basalt meaning it has a low viscosity and eruptions are less violent.
- At destructive plate margins eruptions are more violent and composed of viscous, thick andesitic lava and tephra.
8 - Describe four types of volcanic hazard
8 - Primary hazards: Pyroclastic flow, tephra, lavaflows
- Secondary hazards: Mudflows, landslides, acid rainfall, flooding.
9 - State four ways in which volcanic hazards can be mitigated.
9 - Study of the land
- Study of groundwater levels and chemical composition
- Study of gas emissions and crack detection and shock wave detection.
- Protection measures such as evacuation and hazard drills.
- Land use planning
10 - What are the primary and secondary hazards generated by earthquakes?
10 - Primary hazards: Ground shaking and splitting
- Secondary hazards: Shockwaves, tsunamis, liquefaction and landslides.
11 - List the factors that influence the human impact of earthquakes, giving your explanation for each
11 - Size of the event: The more powerful, the greater the impact.
- Population density: Greater the impact if high population density.
- Degree of preparation: The more educated people are the lower the impact.
- Level of economic development: Higher levels of development mean there are more effective mitigation strategies.
12 - Outline four responses to mitigate the impact of earthquakes
12 - Prediction: Monitoring groundwater levels and animal behaviour, magnetic fields and studying hazard zone maps.
- Protection: Developing understanding, safety drills, building modifications, tsunami protection and warning systems.
13 - Where and why do tropical storms form?
13 - Tropical storms are distributed 5 degrees and 20 degrees and south of the Equator.
- They form due to low-pressure systems, which forms the tropics.
14 - Name three natural hazards caused by tropical storms
14 - Impacts include coastal flooding, damage to buildings, varying degrees of flooding to homes, power line damage, landslides and mudslides.
15 - How can wildfires be beneficial?
15 - If controlled small fires can prevent the build-up of fuel contributing to large, more destructive and dangerous fires.
- The ashes add nutrients to the soil
- They can provide a means to control pests and alien plant species.
