Measures to Cope with Living in Tectonically Active Locations

Question 1

Modifying the event- Volcanic eruptions

Answer 1

• Lava-diversion channels
• Spraying lava to cool it so it solidifies
• Slowing lava flows by dropping concrete blocks

Question 2

Modifying the event- Earthquakes

Answer 2

Nothing can be done to modify an earthquake event

Question 3

Six ways of modifying people’s vulnerability

Answer 3

• Education
• Community preparedness
• Prediction and warning
• Hazard-resistant building design
• Hazard mapping
• Land-use zoning

Question 4

Modifying people’s vulnerability- Education

Answer 4

• Recognising signs of possible eruption
• What to do when an eruption occurs (e.g. evacuation routes; drills to practise what to do when a tectonic event strikes (e.g. in an earthquake, get to open space away from buildings or shelter under a table in a doorway))

Question 5

Modifying people’s vulnerability- Community preparedness

Answer 5

e.g. building of tsunami shelters and walls; strengthening of public buildings (e.g. hospitals, fire stations, schools)

Question 6

Modifying people’s vulnerability- Prediction and warning

Answer 6

Increasing use of technology to monitor particularly active locations (e.g. individual volcanoes)

Question 7

Modifying people’s vulnerability- Hazard-resistant building design

Answer 7

e.g. cross-bracing of buildings to support them during an earthquake; steep-sloping roofs to prevent ash building up

Question 8

Modifying people’s vulnerability- Hazard mapping

Answer 8

e.g. predicted lahar routes; ground likely to liquefy in an earthquake

Question 9

Modifying people’s vulnerability- Land-use zoning

Answer 9

To avoid building in locations identified by hazard mapping

Question 10

Changes in the frequency and impact of tectonic hazards over time

Answer 10

• The number of natural disasters has increased over time but the increase in earthquakes and volcanic eruptions is less pronounced. There has been an increase over the past 50 years; on average there are now 30 volcanic eruptions and earthquakes a year. Data show that earthquakes have a significantly greater impact in terms of number of deaths than volcanic eruptions
• Generally, the greater the magnitude of an eruption or earthquake, the less frequently it occurs. Recurrence intervals indicate that high-magnitude events recur over longer periods of time. High-magnitude, rare events can release large amounts of energy and have the greatest impact on human populations

Question 11

Possible future strategies

Answer 11

• Effectiveness of current strategies needs to be assessed and evaluated in order to draw lessons for the future
• It is not currently possible to make predictions of when and where earthquakes will happen. A specific and reliable “precursor” is needed in order to confidently predict an earthquake event within a specific time and place. So far, the search for such a precursor has been unsuccessful. Most geoscientists do not believe that there is a realistic prospect of accurate prediction in the foreseeable future
• Future research will therefore focus on improving the forecasting of earthquakes
• The UN identifies the alleviation of poverty as a priority in reducing the effects of earthquakes in the future
• Falling buildings are by far the greatest cause of casualties during earthquakes, so it is essential that building design to withstand tectonic events continues to make advances in the future

Question 12

Characteristic human responses to hazards

Answer 12

• Responses occur at different levels: individual, community, national government and international
• Resilience is the sustained efforts of communities to respond to and withstand the effects of hazards
• Hazards are also managed by the integration of prediction, prevention and protection plans
• Prediction is not always possible scientifically but, with careful monitoring, warnings can be issued
• ## Natural hazards cannot be prevented but some of the dangerous secondary impacts can be controlled (e.g. lava flows can be diverted)

Question 13

Characteristic human responses to hazards

Answer 13

• Responses occur at different levels: individual, community, national government and international
• Resilience is the sustained efforts of communities to respond to and withstand the effects of hazards
• Hazards are also managed by the integration of prediction, prevention and protection plans
• Prediction is not always possible scientifically but, with careful monitoring, warnings can be issued
• Natural hazards cannot be prevented but some of the dangerous secondary impacts can be controlled (e.g. lava flows can be diverted)
• Protection aims to minimise the impact of a hazard event. This usually involves adaptations to the built environment (e.g. earthquake-proof buildings, sea defences)
• Risk sharing involves public education and awareness of the measures available to reduce impact (e.g. emergency responses and evacuation procedures)

Question 14

Hazard management cycle- Pre-disaster

Answer 14

• Risk assessment
• Mitigation/prevention
• Preparedness

Question 15

Hazard management cycle- Response

Answer 15

• Warning/evacuation
• Saving people
• Providing immediate assistance

Question 16

Hazard management cycle- Post disaster

Answer 16

• Assessing damage
• Ongoing assistance
• Restoration of infrastructural services
• Reconstruction (resettlement/relocation)
• Economic & social recovery
• Ongoing development activities
• Risk assessment mitigation/prevention