Tectonics EQ3 Flashcards
What is a tectonic mega-disaster?
Have regional or even global significance in terms of economic and human impacts
What characteristics do mega-disasters typically share?
- Large scale spatially or in terms of their economic and human impact
- Due to outsourcing TNCs are often affected, having to halt production
- Problematic in short term and long term
- Communities and governments often required international support
- Can affect multiple countries
- HILP (High Impact Low Probability) this best explains why countries remain poorly prepared
CASE STUDY: Eyjafjallajökull 2010 (Global Air Travel)
Global economic impacts:
- European flight authorities decided to ban all IFR (Instrument Flight Rules) flights for several days
- On 18th april, during worst periods of the eruption, 313 airports across Europe were closed
- Major airlines said to be losing £130million a day
- Globally, airlines lost an estimated £1.05 billion
- Prices of stocks and shares in companies relying on air freight fell steeply
- Demand for jet oil slumped by 2 million barrels a day
- Also producers of specialised crops such as flowers and fruit in Africa and the Caribbean, products left to rot. Kenya alone lost £2.4 million per day
CASE STUDY: Tohoku Tsunami 2011 Global economic impacts
In the short term, there was an impact on production, both in Japan and globally, as supply chains were affected.
Sony, 6 factories closed down, loss of $2.9 billion
-Nissan car production, 4 factories closed, 2,000 cars ready for export were damaged BUT car prices increased by 6% (profit of $3.8 billion)
The Fukushima nuclear power station destruction resulted in a loss of public acceptability in nuclear power, Germany and Italy immediately shut down some of their nuclear reactors
What is a multiple hazard zone?
A place where multiple physical hazards combine to create an increased level of risk for the country and its population.
What are disaster hotspots?
Hydrometeorological hazards. Likely to be where tectonic plate boundaries intersect with major storm belts in areas of high human concentration with low/ medium development.
How might hazard risk vary within a country?
- Cities are centres of economic development, with high population densities and centres of growing population
- They may have huge areas of unplanned, poor quality housing where the urban poor live
- Slums are often on marginal and potentially dangerous land such as river banks and sleep slopes
- Many of the worlds megacities are located in hazard prone areas
- for this reason, large urban areas are often zones of multi hazard risk
CASE STUDY - THE PHILLIPINES - A MULTIPLE HAZARD HOTSPOT
-One of the most disaster-prone countries in the world, has 8/10 of the most at-risk cities from natural hazards in the whole word
It is a lower-middle income country with a high population density
-Typhoons are a significant hazard, affecting the agricultural economy
-Floods are common esp due to high intensity monsoon and typhoon rain
-On zone between Pacific and Eurasian plates 65 destructive events in last 400 years
-37 volcanoes in philippines e.g Mt Pinatubo , lahars significant
-Coastal areas at risk from tsunami.
How many islands are there in the Philippines
Over 7000
What is the population density of the Philippines?
240km2
Describe the worst earthquake event in the Philippines
1990 Rizal city - 1700 deaths and cost £300 million
CASE STUDY COASTAL FLOODING IN THE PHILIPPINES
- Flooding is common due to high intensity monsoon and typhoon rain
- Coastal areas are at risk from local Tsunamis and others in pacific ring of fire.
- Risk raised by coastal development and removal of Mangrove swaps
What is the arrival time for local tsunami’s in the Philippines?
3-5 minutes
Describe the worst Philippines tsunami event - stats and when?
1976 - 5000 dead
CASE STUDY Philippines government response
- Many organisations established to forecast, warn, risk assess, disaster train and educate:
- National disaster co-ordinating council
- Philippine Atmospheric, geophysical and astronomical services
- Land use planning
- Building regulations
What hydro-metrological hazards could make a tectonic disaster worse?
- Intense rainfall (high volume and long duration) can cause Lahars
- On steep slopes, rainwater can easily erode and transport fine grained, loose volcanic sediment and form a slurry, especially if vegetation has not had time to grow back on recent volcanic deposits
- Lake breakout floods that occur without an eruption can also lead to lahars. They commonly occur after a stream becomes blocked by a volcanic landslide or pyroclastic flows that form a natural dam
Can we predict earthquakes?
Cannot be predicted. only areas at high risk can be identified (risk forecasting), plus areas that are likely to suffer severe ground shaking and liquefaction. This can be used for land-use zoning purposes.
“Seismic gaps” = areas that have not experienced an earthquake for some time and are “overdue” can point to areas of high risk
Can we predict volcanic eruptions?
Yes. Monitoring equipment on volcanoes can measure changes as magma chambers fill and eruptions nears.
Tiltmeters and strain meters record volcanoes “bulging” as magma rises and seismometers record minor earthquakes indicating magma movement
Gas spectrometers analyse gas emissions which can point to increased eruption likelihood
Can we predict Tsunamis?
Partially. An earthquake-induced tsunami can NOT be predicted. However, seismometers can tell an earthquake has occurred and locate it, then ocean monitoring equipment can detect a tsunami in the open sea
This information can be relayed onto coastal areas, which can be evacuated. Tsunami monitoring equipment was not present in the Indian Ocean 2004 tsunami so there was no way of warning people - despite there being many hours in which to have done so.
Why do developing countries struggle with volcano monitoring and tsunami warning?
The cost of technology.
Also, it may be more difficult to reach isolated, rural locations with effective warnings
What are the four stages of the hazard management cycle?
Mitigation, preparation, response and recovery
What is mitigation & the aims of this process?
Takes place during and after hazard events. It involves preventing or minimising the effects of hazard events by identifying potential natural hazards and taking steps to reduce its impacts. Main aim = reduce loss of life and properties (largely by helping communities to become less vulnerable)
Actions:
-Zoning and land use planning
-Creating and enforcing building codes
-Building protective structure (such as tsunami sea defence walls)
What is preparedness & the aims of this process?
Takes place before hazardous events. Preparing to deal with a hazard event, minimising loss of life and property, and facilitating the response and recovery stage. Many activities are developed and implemented by emergency planners in both governments and aid organisation.
Actions:
-Creating preparedness plans
-Early warning systems
-Evacuation routes created
-Stockpiling equipment and supplies
-Public awareness raised (e.g by holding earthquake drills)
What is response and what are the aims of this process?
Responding to a hazard effectively. Coping with a hazard. To save lives, protect properties, make sure affected areas are safe and reduce economic losses.
Actions:
-Search and rescue efforts
-Restoring critical infrastructure (e.g power and water)
-Evacuating people where needed
-Ensuring critical services continue (health care and law enforcement)
