Define a natural hazard
A natural hazard is a natural event that has the potential to threaten both life and property. Without people it is just a natural event not a hazard
Define a natural disaster
A natural hazard that causes deaths and damage to goods/property and the environment.
There is no universally agreed scale in which loss has to occur in order to qualify as a disaster.
Define risk
The exposure of people to a hazardous event which may present a potential threat to people or their possessions, including buildings and structures
Define vulnerability
The ability to anticipate, cope with, resist and recover from a natural hazard
Define resilience
Thea ability to protect lives, livelihoods and infrastructure from destruction, and to restore areas after a tectonic hazard has occured
What does Dregg’s Model show?
That hazardous geophysical events (earthquakes, volcanoes and tsunamis) will create disaster when overlapped with a vulnerable population (susceptible to human and/ or economic loss because of their location)
Disaster can only occur when a vulnerable population is exposed to a hazard
Why do people remain exposed to risk?
- Cost-benefit - the benefit of staying in a hazardous location may outweigh the risks of staying there
- Poor risk perception (it wont happen to me!)
- Russian roulette reaction - the hazard will happen no matter what you do
- Lack of alternative options - this may be for economic reasons, no other options than living in the hazardous locations
- Unpredictability - many hazards are not predictable; the time and magnitude can catch people out
- Dynamic hazards- there may be an increase or decrease in hazards over time
How can complex infrastructure make you more economically vulnerable?
- Nuclear fallout e.g 2011 Japanese Tsunami (Fukushima)
- Collapse of buildings and infrastructure
- Over reliance on defences, that may fail
- Fire from damaged gas pipes
- Failure of dams
When does a hazard become a disaster?
The EM-Dat (international disaster data base for assessing and identifying disasters) suggests the following criteria:
- 10 + people are killed
- 100+ people are affected
- International assistance is called for
- State of emergency is declared
Explain the hazard risk equation (wont get maths question but may have to explain in words)
R= (HxV)/ C
R= Risk H= Frequency/ magnitude V = vulnerability level C= capacity to cope Risk (R) increases as hazardous (h) events become more common, people become more vulnerable (v) and their capacity to cope (C) decreases.
Comparing the respective vulnerabilities of two places (Case Study ish) for older population
Myanmar:
-Significantly high natural hazard component due to the potential for tsunami and earthquakes
-Moderate risk though relatively low vulnerability score - there have been few natural shocks in recent years
- Poor coping capacity; low level of internet/ mobile phone access for older people; education is poor
-Ranked 7th out of 190 nations for overall risk
Japan:
-Subject to a range of natural hazards and is highly exposed
-Vulnerability is high compared to other wealthy nations due to the ageing population but is still low risk
-Good capacity to cope due to effective gov, internet access etc for elderly people and education
-Although highly exposed, Japan ranks 133rd out of 190 nations thanks to its coping capacity and lower levels of vulnerability
What is the PAR model and its various components?
Practice drawing out diagram
The Pressure and Release model shows how the characteristics of a hazard and a place connect to create a disaster. model looks at the underlying causes of a disaster. Disaster occurs when two opposing forces interact: The hazard itself and the processes that create vulnerability
Progression of vulnerability include: root causes, dynamic pressures and unsafe conditions which lead to disaster when combined with natural hazards.
Explain the root causes of the progression of vulnerability (PAR model)
The root causes of vulnerability is affected by who has control and who has power in society and who has access to resources: Limited access to: -Power, Structures, resources Ideologies: -Political systems, economic systems
Explain the dynamic pressures which progress the vulnerability of a place (PAR model)
Dynamic pressures create unsafe conditions. A country that is poor will not spend time or money enforcing building codes which means that buildings will be poor built
Lack of: investment, training, press freedom
Macro-forces: rapid pop change, rapid urbanisation, deforestation
Explain the unsafe conditions which are caused by dynamic pressures and root causes? (PAR MODEL)
- Physical environment
- Local economy
- Social relations
- Public Actions
What is a hazard profile?
A diagram that shows the main characteristics of different types of tectonic hazard, this could be for a single hazard or show multiple, allowing comparisons. Helps to compare physical processes and helps decision makers rank and identify the hazards that should be given the most attention and resources.
How do hazard profiles demonstrate the importance of magnitude?
The magnitude is seen as the key factor in determining the scale of the impact as even rich countries struggle to cope with mega events such as the 2011 Japanese Tsunami
How do hazard profiles show the importance of frequency on the impacts of an earthquake events?
The frequency of events are important as the more frequent an event the more likely there is to be a well planned disaster management scheme in place, reducing the impacts as evidenced by the Samoa 2008 Tsunami. Thus, the low frequency, high magnitude extreme events (1 in a 1000-year events) often cause the largest impacts as prediction is difficult and prevention is impossible such as the Indian Ocean tsunami 2004
How do hazard profiles express the importance of spatial area on the impacts of an earthquake hazard?
The areal extent (spatial area) can determine the scale of impacts as earthquakes which affect a greater area cause greated impacts such as in the Afghanistan 2015 Earthquake
How do hazard profiles show the importance of spatial predictability on the impacts of an earthquake?
Spatial predictability is a vital factor as area with blind faults (such as Kobe 1995) lead to increased risks due to a lack of understanding of the magnitude of the risk. Areas far away from other earthquake belts (Christchurch 2011) can also have higher than expected impacts due to a lack of spatial predictability
How do hazard profiles show that strong governance has an affect on the impacts of an earthquake diaster?
Strong governance can lead to very effective management of immediate disaster recovery, e.g Sichuan earthquake in China 2008, as well as the development of longer term education and community preparation such as the education programmes in California. However, management is expensive and countries with a low level of development cant afford the investment required to reduce the risks of earthquake events such as in Haiti 2011
How do hazard profiles show the importance of geographical factors on the impacts of an earthquake?
They are a key factor in determining impacts as urban areas with high population densities can have large impacts with relatively small magnitude earthquakes such as in Bam, Iran 2003.
How can governments use hazard profiles to manage impacts?
- Hazard profiles help government and other organisations to develop disaster plans and educate locals
- Implement land-use zoning to keep danger areas clear
- Use hazard-resistant designs
- Educate local people on what to do in a disaster
- Ensure local community preparedness
- Management strategies to manage losses; insurance and aid deployment
- Could help to plan the scale of the emergency response –> larger spatial areas would be harder to respond to i.e Sichaun China; Christchurch was easier
- Governments can only implement responses they have the economic capacity to afford
Why do people in developing and emerging countries have higher vulnerability?
- Peoples basic health and nutritional status correlates strongly with their ability to survive disruptions to their lives and livelihood
- Nutrition affects peoples ability to fight disease, during disaster situations people can be forced to find shelter in cramped conditions and come in close contact with each other passing disease
- e.g Haiti 2010 9,000 people died of cholera
- Higher incidence of HIV and Malaria worsen disaster risks
- Drought, violence and armed conflict, which are more frequent in developing countries and may turn natural hazards into disasters
- Note that disaster risk factors can be internal such as conflict or external such as climate change
