Tectonic Hazards EQ3 - Hazard/disaster management

Question 1

What do the overall longer term natural hazard trends show?

Answer 1

• total number of recorded hazards has increased over past 50 years
• number of reported disasters seems to be falling
• number of deaths lower than in recent past, but there are spikes with mega events
• economic costs increase significantly since 1960
• number of people affected is increasing for some hazard and disaster types

Question 2

Why are disaster statistics controversial?

Answer 2

• depends on whether direct or indirect deaths from subsequent hazards/associated diseases are counted
• local or regional events in remote places often under-recorded
• declaration of disaster deaths and casualties may be subject to political bias
• statistics on major disasters hard to collect, particularly in LICs
• time trend analysis is difficult

Question 3

What is a mega disaster?

Answer 3

A high magnitude, high impact, infrequent disaster, characterised by impacts extending beyond the country immediately affected

Question 4

What are the key characteristics of tectonic mega-disasters?

Answer 4

• large scale disaster (either spatially or in terms of human/economic impact)
• due to scale, pose serious problems for effective management
• scale of impact means communities but usually government as well, require international support in immediate aftermath as well as longer term recovery

Question 5

What is a HILP event?

Answer 5

A high impact, low probability event

e.g. 2010 Haiti earthquake

Question 6

What are the consequences of HILP events?

Answer 6

Impacts spread rapidly across both economic and geographic boundaries leading to other impacts which are difficult to plan for

Question 7

What is a multiple hazard zone?

Answer 7

A place where a number of physical hazards combine to create an increased level of risk for the country and it’s population. Often made worse by vulnerable population or if area suffers repeated events

Question 8

What is a disaster hotspot?

Answer 8

A country or area that is extremely disaster prone for a number of reasons

Question 9

What are the characterstics of a hazard hotspot?

Answer 9

Intersection of tectonic and hydro-meterological hazards and vulnerability, leading to a hotspot which is likely to be where plate boundaries intersect with major storm belts in areas of high human concentration in low or medium developed countries

Question 10

Why are large urban areas often zones of multiple hazard risk?

Answer 10

• economic cores
• centres of growing population due to rapid urbanisation
• many countries have huge areas of unplanned, poor quality housing where the growing numbers of urban poor live - located on marginal land

Question 11

Can scientists forecast earthquakes?

Answer 11

Earthquake risk can be forecast since it is based on a statistical likliehood of an event occurring at a particular location

Question 12

Can earthquakes be predicted?

Answer 12

Currently, it is not possible to make accurate predictions of when and where earthquakes will happen. For this to happen, it would be necessary to identify a diagnostic precursor - a characteristic pattern of seismic activity or another change that indicated the onset of an earthquake

Question 13

What are the 4 stages in the hazard management cycle?

Answer 13

Response
Recovery
Mitigation
Preparedness

Question 14

What are the 4 stages of Park’s Model?

Answer 14

• pre-disaster
• relief
• rehabilitation
• reconstruction

Question 15

What does Park’s disaster response curve demonstrate?

Answer 15

It can be used as a framework to better understand the time dimensions of resilience, from when a hazard strikes to when a place or community returns to ‘normal’ operation

Question 16

How are earthquake events modified?

Answer 16

Micro approaches - strengthening individual buildings and structures against hazardous stress
e.g. schools and hospitals and public buildings strengthened through ‘retrofit’

Question 17

How are tsunami events modified?

Answer 17

No technologies can prevent tectonic disturbance, but some regions and communities have put engineering strategies in place - e.g. tsunami walls, replanting of coasts with dense coastal forests to create buffer zones

Question 18

How are volcanic events modified?

Answer 18

May be possible to modify a volcanic event once eruption and lava flows have started by diverting or chilling flows - e.g. Heimaey 1973

Question 19

What are some strategies to modify the event?

Answer 19

• land use zoning
• hazard-resistant design
• engineering defences
• diversion of lava flows

Question 20

What are some strategies to modify vulnerability and resilience?

Answer 20

• prediction, forecasting and warnings (hi-tech monitoring)
• improvements in community preparedness
• working with groups and individuals to change behaviours to reduce disaster risk (education)

Question 21

What are some strategies to modify loss?

Answer 21

• emergency, short and long term aid
• insurance

Question 22

What is modifying the event?

Answer 22

BEFORE hazard strikes (long term)
Mitigating impacts of hazard by reducing areal extent or magnitude, not always possible (relies on high cost technology)

Question 23

What is modifying the vulnerability?

Answer 23

BEFORE hazard strikes (short term)
Get people out of the way (prediction) or help them cope with impacts (build resilience)

Question 24

What is modifying the loss?

Answer 24

AFTER hazard strikes (long and short term)
Reduce losses by acting to aid recovery and reconstruction