other than tectonic hazards, what is the other hazard called and why have they become more common in recent years?
Hydro-met hazards (hydro-meteorological hazards)
hazards such as floods, storms, cyclones and drought. increasing possibly due to global warming and human environmental management issues such as. deforestation.
what are some trends of tectonic hazards?
- hasn’t been a change in the number of tectonic hazards since 1980; 15-40 each year
- the trend for earthquake economic losses is upwards, averaging about $20-40 billion per year.
what is a mega-disaster?
a high magnitude, high impact, infrequent disaster that affect multiple countries directly or indirectly meaning their impacts are regional or global.
what are two examples of mega-disasters and what were their main impacts?
2011 Japan tsunami- only effected Japan directly but the economic impacts had global consequences as Japan faced disruptions to ports, factories and power supplies which effected supply chains and global business transactions
2010 Eyafjallajokul eruption- over 20 European countries were affected by total or partial closure of airspace as the Asch cloud disrupted air travel leading to 100,000 cancelled flights costing over £1 billion in losses.
what is a multiple hazard zone?
regions prone to two or more hazards, and in some cases can interact to produce complex disasters.
what is meant by a prediction?
knowing when or where a natural hazards will strike on a spatial and temporal scale that can be acted on meaningfully in terms of evacuation
what is meant by forecasting?
much less precise than predicting, it provides a percentage chance of a hazard occurring
e.g 25% chance of a magnitude 7 earthquake in the next 20 years
can you predict earthquakes? give further information
NO
- only areas at high risk and areas likely to suffer from severe ground shaking and liquefaction can be identified (risk forecasting) and used for land use zoning
- ‘seismic gaps’ ; areas that haven’t experienced an earthquake for some time or are ‘overdue’, can signify high risk.
can you predict volcanic eruptions? give further info
YES
- monitoring equipment on volcanoes can measure changes as magma chambers fill when an eruption is nearing
- Tiltmeters and strain meters record volcanos magma movement when it rises
- gas spectrometers analyse gas emissions which can signal an increased likelihood of an eruption
can you predict a tsunami? give further info
PARTLY
- an earthquake induced tsunami cannot be predicted
- however seismometers can detect and locate an earthquakes occurrence, then the ocean monitoring equipment can detect a tsunami
- this info can be relayed to coastal areas to start preparations for evacuated.
what do perditions of events rely on? and why isn’t it accessible to all?
technology
developing countries like India in 2004 don’t have the motoring equipment meaning warning systems are as accurate and quick enough to be effective
what does the hazard/disaster management cycle show?
the different stages of managing a hazard in an attempt to reduce the scale of the disaster.
shows:
preparedness-community education, predictions, warning and evacuation systems
mitigation-acting to reduce the scale of the next disaster; land use zoning, hazard-resistant buildings and infrastructure
response-immediate help in the form of rescue to save lives and aid to keep people alive
recovery-rebuilding infrastructure, and services, rehabilitating the injured.
what do the recovery stages depend on?
- the magnitude of the disaster
- development level (the lower, the more severely affected)
- governance (better= well diverted resources
- external help
what is the Parks Model and what does it show?
a disaster response curve
provides a simple visual illustration of the impacts of a disaster and can be used to compare different hazard events as shown by the curve
what are the three ways disasters can be managed by modifying impacts?
- modifying the event: mitigating the impacts of hazard by reducing areal extent and/or effective magnitude
- modifying vulnerability: evacuate people or help cope with impacts by building resilience
- modifying loss: reduce the short and long term losses by acting to aid recovery and reconstruction.
what is meant by a hazard resistant design?
invoices constructing buildings and infrastructure that are strong enough to resist tectonic hazards. in the case of an earthquake, they are called aseismic buildings.
what are some ways to modify the EVENT and their strengths and weaknesses?
LAND USE ZONING: prevention of building on low-lying coastal land (tsunami), close to volcanoes and areas of high ground shaking and liquefaction risk.
+low cost
+removes people from high risk areas
-prevents economic development on high valued land (coastal tourism)
-requires strict, and enforced planning rules
ASEISMIC BUILDINGS: cross bracing, counterweights and deep foundations to prevent earthquake damage.
+prevents collapse
+protects both people and the property
-high cost
-older and low income homes are rarely protected
TSUNAMI DEFENCE: sea walls and breakwaters prevent waves travelling inland
+reduces damage dramatically
+provides sense of security
-high cost
-ugly and restricts development and use of coast
LAVA DIVERSION: channels and barriers and water cooling used to divert or slow lava
+diverts lava
+relatively low cost
-only works on low basaltic lava
-the majority of harmful volcanoes are not this type^.
what is cry wolf syndrome?
something that occurs when predictions and evacuations prove to be wrong, so people are less likely to believe the next prediction and warnings and therefor fail to evacuate
what are some ways to modify VULNERABILITY and the advantages and disadvantages?
HIGH TECH SCIENTIFIC MONITORING: used to monitor volcano behaviour and predict eruption
+warnings and evacuation saves lives
-costly so not all volcanoes are monitored
-doesn’t prevent property damage
-may suffer from cry wolf syndrome
COMMUNITY PREPAREDNESS AND EDUCATION
+low cost, often implemented by NGO’s
+can save lives through small actions
-doesn’t prevent property damage
-harder to implement in isolated rural areas.
ADAPTATION: moving and relocating to safe area
+would save both lives and property
-disruption to homes, lives and traditions
what are some ways to modify the LOSS and the advantages and disadvantages?
SHORT TERM EMERGENCY AID: search and rescue followed by emergency food, water and shelter
+reduce death toll
-high cost
-emergency services are limited in poorly equipped developing countries
LONG TERM AID: reconstruction plans to rebuild an area and possibly improve resilience
+reconstruction builds in resilience through land-use planning and better construction methods
-high cost
-needs are quickly forgotten by media after initial disaster
INSURANCE: compensation given to people to replace their losses
+allows people to recover economically, by paying for reconstruction
-doesn’t save lives
-few people in developing regions have insurance
