Hazards Flashcards

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1
Q

What is a natural hazard and a disaster?

A

A natural hazard is a perceived event that threatens both life and property and could cause disruption to human systems (e.g. communication)

A disaster occurs when a hazard causes severe harm to a community

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2
Q

What are the different types of hazards?

A

Geophysical hazards originate from the solid earth and driven by the Earth’s internal energy

Atmospheric hazards originate in the atmosphere, driven by meteorological and climatic processes

Hydrological hazards originate in surface and subsurface freshwater and saltwater, driven by processes in water bodies

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3
Q

Why does vulnerability to a hazard vary?

A

Vulnerability may vary over time and space because wealth and technology play a huge part in the impacts of a natural hazard event.
Richer countries are more able to protect themselves (e.g. effective emergency services), more aware of risks through education.

Poorer countries are extremely vulnerable as urban areas grow so rapidly it forces people to live in hazardous conditions (e.g. on steep hill sides which exposes them to landslides)

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4
Q

Why do people forcibly make themselves vulnerable to hazards?

A

People may make themselves vulnerable by living in high risk areas because:

  • The events are unpredictable (magnitude and frequency)
  • Lack of alternative (social, economical and political factors may prevents someone from moving)
  • Level of risk may have changed over time (more hazardous, e.g. deforestation of rainforests increases risk of flooding)
  • The benefits of living there may outweigh the losses
  • The perception of the individual (e.g. fatalism)
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5
Q

What are the perceptions to hazards?

A

Fatalism: a view of a hazard event that suggests that people cannot influence the outcome, nothing can be done to mitigate it

Adaptation: attempts by people/communities to live with hazard events by adjusting their living conditions which reduces their level of vulnerability

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6
Q

What are some characteristics that can influence hazard perception?

A
  • socio-economic status (e.g. in wealthier areas there is a sense of being prepared and preventing disaster whilst deprived areas look at it as a way of life)
  • Level of education
  • Occupation/employment status
  • Religion, culture and ethnic background
  • Family status
  • Past experience
  • Values, personality and expectations
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7
Q

What are the perception responses to hazards?

A

Fatalistic perception makes people believe their fate is at “God’s Will” so the losses are inevitable and any mitigation/prevention is futile

Adaptation perception leads to people preparing, predicting and protecting with the available technology or funds of the area, due to the belief they can survive

Fear pushes people to move away as they will feel to vulnerable to any event, unable to live there)

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8
Q

Hazard perception case study: Haiti

A

Haiti perception to natural hazards in fatalistic, nothing can be done to mitigate hazards

Economic characteristics:

  • Poorest country in the Western hemisphere
  • Poor quality of settlement
  • Corrupt and poor government

Cultural characteristics:

  • Heavy voodoo beliefs (mixture between Catholicism and African beliefs) where God determines when a person lives and dies (God’s Will)/ destiny decided life
  • Hope in the next life things will be better (escape poverty)
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9
Q

What is distribution, frequency and magnitude?

A

Distribution: refers to the spatial coverage of the hazard

  • Can have a very localized effect or a global effect
  • Can reference the area where the hazard is likely to occur

Frequency: The distribution of a hazard through time

Magnitude: the assessment of the size of the impact of a hazard event

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10
Q

What are primary and secondary effects?

A

Primary effects are the impacts that are directly caused by the natural hazard event whilst Secondary effects are a direct results of the primary effects

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11
Q

Name 3 human responses to the threat of hazards?

A
  1. Risk Sharing involves prearranged measures that aim to reduce the loss of life and property damage through public education, awareness programmes, evacuation procedures and provision of emergency supplies
  2. Integrated Risk Management: the process of considering the social, economic and political factors involved in risk analysis and deciding actions that should be taken to minimize damage
  3. Prediction: the ability to give warnings so that action can be taken to reduce the impacts of hazard events
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12
Q

What is the DEGG model?

A

Analysing the impact, which element had the biggest impact (whichever circle in bigger gives the best explanation of why a hazard became a disaster), how the 2 elements are involved in the outcome

Characteristics of hazard/ evidence of disaster/ characteristic of place

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13
Q

What is the hazard risk equation?

A

Analyses the risk (loss of property/life etc)

  • Shows how all the elements interact with each other (complexity)
  • Judgement of how risky a hazard is becoming a disaster
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14
Q

What is the hazard management cycle?

A

4 stages of preparedness, response, recovery and mitigation

Teaches us how people are responding to hazards and shows how they can improve effective management. Allows us to analyse the response (what was positive and negative) and evaluate the management (what they did, when and anything they left out).

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15
Q

What is the park model/disaster response curve?

A

Teaches us how effective is the management response is, how well do they prevent or improve quality of life and evaluate the response over time.

Evaluate the recovery/resilience/response/management…

  • If a region is more prepared for a natural hazard event, the less the quality of life will fall!
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16
Q

What determines explosivity of a volcano?

A

The explosivity of a volcanic eruption is determined by the viscosity of the lava (how well the lava flows)

Basaltic lava – low viscosity, less silica
Andesitic Lava – high viscosity, traps gas, builds pressure, more explosive
Rhydilic lava

  • Abundance of silica polymers leads to high viscosity
  • Shape and characteristics of volcano are determined by lava
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17
Q

What are the different types of volcanoes?

A
Volcano types:
Shield
Composite/Stratovolcano
Fissure
Dome 
Ash-cinder
Caldera
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18
Q

Assess the extent to which people’s perception of hazards is likely to effect their responses to them [9 marks]

A

HOW THIS IS MARKED:

  • outlining different perceptions of hazards
  • how perceptions relate to the responses
  • how do other factors affect their response to hazards (e.g. wealth may allow someone to protect themselves or be helpless and education gives awareness to those in hazardous areas)
  • short conclusion of how far perception of hazards affect responses
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19
Q

What is an ocean ridge?

A

Underwater constructive plate boundaries move apart allowing magma to force its way to the surface, consequently cooling to form new crust (ocean ridge). New crust is forcing down on the plate causes sea floor spreading, with the added force on the end of the plate being subducted.

Iceland has the mid-Atlantic Ridge passing through it and has fairly gentle sided volcanoes from the low viscosity of basaltic lava with frequent but gentle eruptions

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20
Q

How do volcanoes form generally?

A

The deeper a plate descends in a subduction zone, the hotter the surroundings become in the mantle and that mixed the friction, the oceanic plate melts into magma in the Benioff Zone. This less dense magma starts to rise as plutons, reaching the surface to form volcanoes.

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21
Q

What is a rift valley?

A

At constructive plate margins across continental areas the brittle crust falls apart (as it moves apart) and areas of crust drop between parallel faults forming rift valleys. Crust is much thinner, suggests that the tension within the crust is causing it to thin. Through the thinning, separating crust magma forces upwards creating composite, active volcanoes along the East African Rift.

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22
Q

What are island arcs?

A

A concentration of radioactive elements below the crust creates a hot spot. This causes plumes of rising magma to eat into the plate above, lava breaks through the surface and forming shield volcanoes as the basaltic lava flows slowly but far.

As the hot spot is stationary but the plate above moves a island arc/line of volcanoes is formed, for example the Hawaiian Islands, the older volcanoes put so much pressure on the crust subsidence has occurred.

E.g. West Indies and Hawaiian islands

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23
Q

How is the magnitude of volcanic eruptions measured?

A

The magnitude of volcanic eruptions are measured by the VEI scale (Volcanic Explosivity Index), scale of 0 to 8 (logarithmic scale). Critics do point out that it doesn’t take into account the amount of gas emitted

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24
Q

What are the primary effects of a volcanic eruption?

A

Lava Flows
Tephra (volcanic bombs of fine ash)
Pyroclastic flows (formed of hot gas over 800 degrees and tephra, can travel up to 700km/h)
Volcanic Gases (includes CO2, CO, hydrogen sulphide, sulphur dioxide and chlorine, can be fatal)

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25
Q

What are the secondary effects of a volcanic eruption?

A
Climatic change
Acid Rain
Floody (ice caps or glaciers melt)
Landslides
Lahars (volcanic ash mixing with water and flowing downhill)
Tsunami
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26
Q

Do volcanic hazards show a relationship between hazard intensity and areal extent?

A
  • Primary hazards tend to have a small areal extent but a high hazard intensity
  • Secondary hazards tend to have a large areal extent and a lower hazard intensity
  • However lahars and tsunamis have a much higher hazard intensity and a large areal extent
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27
Q

How can people prepare for a volcanic eruption?

A
  • emergency evacuation plan
  • education
  • allows for a shorter recovery time
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28
Q

How can people protect themselves from volcanic eruptions?

A
  • Identifying areas of the highest risk and land use planning completely avoids building in high risk areas

Digging trenches, dropping blocks into lava and using explosives are all methods to divert lava from settlements/gives people a longer time to evacuate
- In Hawaii they have barriers across valleys to protect environment

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29
Q

How can people predict a volcanic eruption?

A

Warning Signs:

  • land swells
  • hundreds of very small earthquakes (use a seismometer to detect any earthquakes)
  • higher sulphur content in gas emissions (gas samples and chemical sensors can measure levels)
  • temperature volcano rises (thermal imaging techniques and satellite cameras)
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30
Q

How do you spell the icelandic volcano?

A

Eyjafjallajökull

31
Q

DEGG model for the Eyjafjallajökull volcanic eruption April 2010?

A

Characteristics of the hazard:

  • 4 on VEI scale (constructive)
  • steam created a highly explosive eruption and fine grained ash was picked up by jet stream
  • eruption lasted longer than a month (1821 magma chamber reactivated)
  • glacier melt on top of the stratovolcano caused flooding

Evidence of a disaster:
- 0 deaths and 1000 evacuated
- crops, services, homes and roads damaged
· £130 million per day loss to airlines as airports across Europe forced to shut down due to ash

Characteristics of the place:

  • 28th richest country in world
  • Nobody lives below poverty line (officially)
  • extensive management (land use planning and education)
32
Q

DEGG model for the Mt Nyiragongo (Congo) volcanic eruption, January 2002

A

Characteristics of hazard:

  • 1 on VEI scale (constructive)
  • earthquake of 5 on richter scale
  • lava flow of 90km/ph
  • 13km volcanic fissure

Evidence of disaster:
- 147 deaths and 350 000 fled
· drinking water was poisoned many suffered dysentery
· looting and public disorder
· unemployment high as lava destroyed many establishments

Characteristics of place:

  • 228th richest country
  • 68% of population live below poverty line
  • Was still recovering from a civil war (1994-2003) where 5 million were killed
  • Dense urban population in Goma (15km away from volcano)
33
Q

Eyjafjallajökull Hazard Management Cycle?

A

Pre disaster:

  • scientists constantly mitigate and monitor volcano
  • community preparation and education (+ land use planning)

Response:

  • 1000 evacuated before flooding and created exclusion zones
  • flight restriction for 6 days because of ash
  • closed roads in case of lahars (designed to be swept away)

Post Disaster:

  • studying the eruption to understand what to do better
  • rebuilding of homes (insurance)
  • switched attention to neighbouring volcano Katla as magma was rising beneath
34
Q

Congo volcanic eruption hazard management cycle?

A

Pre-disaster:

  • no action even after tremors and other warning signs ignored (gases)
  • no preparation in place

Response:

  • 350 000 fled to Rwanda (no resources to manage them there)
  • all shelter and food given by aid agencies (Red Cross gave millions)
  • Looting

Post Disaster:

  • no long term aid because of civil war
  • 320 000 left homeless
  • slow to rebuild Goma’s infrastructure
35
Q

Evaluate the effectiveness of the hazard management cycle in mitigating the impact of volcanic eruptions?

A

It is/it is not effective effective…

  • evidence of an eruption impact being mitigated (or not) by management
  • how effective was planning in enabling this mitigation
  • can you make reference to the different stages of model?

Conclusion:
Not effective in mitigating impacts
- only wealthy countries are able to utilise the cycle
- only a format, useless when not being used

36
Q

Why is California a multi-hazardous zone?

A

Because there is a variety of hazard threats which occur across the whole of California:

  • wildfires (concentrated in around the central valley)
  • tsunamis
  • earthquakes
  • volcanoes
  • landslides
  • storms
  • drought (widespread, worst is concentrated in the South-West)
37
Q

Are there any aspects of life in California that increase hazard risk?

A
  • Employment and economical growth brings lots of migration (belief that the benefits of living there outweigh the risks)
  • Ignorance towards the risk, faulty knowledge leads to building homes in high risk areas (earthquakes, landslides and wildfires)
  • Chaparral vegetation is adapted to burn easily (for germination) and the slopes increase wind speed to carry fire further
  • Idyllic Californian lifestyle is associated with coastal living, puts people in hazardous places for landslides
38
Q

Are there any aspects of life in California that decrease hazard risk?

A
  • Earthquake resistant/proof buildings
  • Emergency services and planning by FEMA
  • more of a social issues no physical solution
  • community resilience to overcome everything
39
Q

How would you describe peoples reaction to the threat of hazards in California (and their hazard perception)?

A
  • People’s perception of risk is faulty
  • Denial mechanisms (denying it will happen to them)
  • Some acknowledge the risks but choose to ‘tune’ it out
  • Seen when wildfires occur, find people to blame and not the location of the homes
40
Q

Evaluate the economic and cultural determinants of hazard perception?

A

California: entrepreneurial culture = hazard perception is adaptation and invest wealth and technology
- however they do have a denial of risk in some parts (faulty) = build homes in fire risk zones (chaparral ecosystems)

Haiti: fatalistic hazard perception from voodoo culture (life is decided by destiny) however they also have lots of economic problems of corrupt gov & weak economy (explained by culture & economy)

Societies are responsible for hazard outcomes, a wealthy & risk taking one will create adaptation perception, and a poverty stricken, voodoo society will create a fatalistic society

41
Q

What is the theory of continental drift?

A

Published by Wagner in 1912
- That today’s continents have resulted in the splitting and moving of the supercontinent pangea from 300 million years ago

42
Q

Why was the theory of continental drift unpopular at first?

A

Because there was no evidence as to how or why the continents were moving so he was unable to explain how continental movement takes place

43
Q

What was the new discovery to provide the evidence supporting continental drift?

A

Mid Atlantic Ridge demonstrated the process of sea-floor spreading and the movement of continents

44
Q

Evaluate the evidence for theory of continental drift

A

The oldest evidence is the weakest evidence as it couldn’t explain how continents were moving

  • The apparent closeness of coastlines of South America and Africa suggests they were once joined (Pangea) however there’s overlapping and gaps
  • Identical fossils found in different parts of the globe

Following the Second World War some evidence was provided for sea-floor spreading which is one reason why Pangea might’ve moved apart from sonar studies

Today we have technology to show us the movement in real time and evidence will get stronger as time passes
- specific movements of crust can be accurately monitored by satellites

However none of it is conclusive evidence as nothing explain all of the movement

45
Q

Describe mantle convection as a driver of plate tectonics

A
  • hotspots around the earth’s core generate thermal convection currents within the asthenosphere
  • warmer material is less dense and rises, cooler material is more dense so sinks
  • currents cause magma to rise towards crust and spread before cooling and sinking
  • this circulation of magma drive movement of lithosphere and crust from the friction between asthenosphere and lithosphere dragging and pulling plates
46
Q

Describe ridge push as a driver of plate tectonics

A
  • rising magma pushes the ridge high above the seafloor
  • thickness and weight of rock increases away from ridge
  • these characteristics create a gravitational force which speeds up the process of seafloor spreading
  • accelerating the moving apart of plates
47
Q

Describe slab pull as a driver of plate tectonics

A
  • weight and relative density of descending slab is higher than surrounding material
  • slab is colder than surrounding material (less buoyant)
  • gravity-generated force pulls subducting plate downwards (adds to influence of magma convection)
48
Q

What is happening at destructive plate boundaries?

A
Mantle convection (rising magma towards crust) and opposite movement of convection currents pushes plates together
- oceanic plate is more dense than continental so sinks (cooler material in the mantle is more sense so it sinks)

Slab pull is also playing a part as the gravity generated force is pulling the subducting plate downwards
- slab pull is increasing the speed of subduction

49
Q

What is happening at a constructive plate boundary?

A

Mantle convection

  • warmer material is less dense and rises towards the crust, spreading outwards
  • friction between asthenosphere and lithosphere pulls the plates
  • new crust is formed by magma rising into the gap and cooling

Ridge push
- gravitational force downwards of the ridge will create a slight push

50
Q

What is happening at a conservative plate boundary?

A

Plates are going at different speeds because there are different magnitudes of forces of slab pull and ridge push on the plate

51
Q

Why is plate tectonics still just a theory?

A
  • we can’t witness the drivers of the movement
  • not been proven as we can’t see the mantle and what’s happening there
  • hard to be sure about the drivers when the plates are moving at different speed
  • questioning what is the balance between pulling and pushing
52
Q

What is an earthquake?

A

A sudden violent shaking of the ground as a result of movements within the Earth’s crust

53
Q

What are the strengths and weaknesses of the two contrasting approaches for measuring earthquake magnitude?

A

The MMS scale measure the release of energy

  • quantitative data of energy release allows clear comparison of scale of events
  • doesn’t tell us about what happens to the people

The mercalli scale

54
Q

Do seismic hazards show a relationship between frequency and magnitude?

A

As the frequency of seismic hazard increase the magnitude decreases

  • for example constructive plate boundaries have the highest frequency but usually the lowest magnitude however constructive and conservative plate boundaries have high magnitude seismic hazards but are less frequent
  • low magnitude earthquakes = high frequency (tend to), conservative plate boundaries are in the middle of the distribution
55
Q

What are the primary hazards of a seismic hazard?

A

Ground shaking and ground rupture

56
Q

What are the secondary hazards of seismic hazards?

A

Landslides/avalanches, tsunamis (not much warning), fires, soil liquefaction and building collapse

57
Q

Do earthquake hazards show a relationship between hazard intensity and areal extent?

A
  • most earthquake hazards have a high hazard intensity but small areal extent, few have large areal extent
  • primary hazards tend to have a high hazard intensity but small areal extent, for example ground rupture
  • some secondary hazards such as soil liquefaction and building collapse are the same
  • other, secondary hazards such as landslides have a larger areal extent
  • tsunamis are the exception with a large areal extent and a high hazard intensity
58
Q

Assess the factors that determine the impact of an earthquake?

A

The physical characteristics of an earthquake can influence its impact. The greater the energy release and depth of focus will influence the extent of shear and surface waves
- these cause the greatest damage to buildings and in the right circumstances possibility of soil liquefaction or other secondary hazards (high hazard intensity with low areal extent, except tsunamis)

  • 2010 Chile earthquake had a magnitude of 9MMS and less than 100 people died
  • Haiti earthquake in the same year had a magnitude of 7MMS and killed over 7MMS
  • buildings and fires lead to the greatest social cost which the extent is determined by management
59
Q

What are the implications to management for seismic hazards?

A
  • earthquakes don’t kill people buildings do therefore buildings need to be reinforced and building codes should be improved
  • transport, communications and utilities must be made secure or the response to the hazard will be hindered
  • land use planning, not building schools or hospitals on geology vulnerable to liquefaction
60
Q

What is the DEGG model for the Haiti (2010) earthquake?

A

Hazard:

  • 7MMS on destructive plate boundary
  • focus was deep, 13km

Disaster:

  • 160,000 deaths
  • 188,000 buildings collapsed
  • $11.5billion in damages (120% of GDP)

Place:

  • unconsolidated geology and steep terrain
  • corrupt government
  • building codes not enforced
  • dense, informal settlements
  • poorest country in the western hemisphere
  • high poverty (19% have access to sanitation)
  • fatalistic attitudes
61
Q

What is the DEGG model for the Napa earthquake in California?

A

Hazard:

  • 6MMS on conservative plate boundary
  • shallow focus of 11km

Disaster:

  • 1 death and 200 injured
  • only older buildings suffered damage despite being retrofitted (4 destroyed)
  • fires broke out
  • $362 million in damages

Place:

  • stable government, building codes enforced including landuse planning
  • well planned residential zones
  • excellent emergency services
  • adaptation
62
Q

Do the characteristics between the two places explain the differences in impacts of hazards?

A

Yes they do as in Haiti there is a poor and corrupt government which don’t enforce building codes so homes are built unfit for withstanding an earthquake as well as the potential of being built on vulnerable geology, in Napa the opposite is the case

63
Q

Evaluate the strategies to manage seismic hazards

A
  • The best strategies need to take place pre-disaster (construct hazard-resistant buildings, prediction, education and landuse planning)
  • during a response, aid should be in cash as people can buy essentials they need and rebuild their homes if they can
  • mitigation shortens relief and starts reconstruction quickly, making sure local economy can recover and jobs can be held
  • reconstruction can be the most effective post-disaster strategy as the community has the potential to be built back up stronger
  • however local communities must have control over the recovery plan and allow them to bury any dead for emotional recovery
64
Q

How does the nature of the seismic hazard can influence the potential impacts on the Bay Area?

A
  • Scale greater than 6MMS
  • 2 faults (San Andreas and the Heyward)
  • Frequency circa 150 years (Heyward is long overdue)
  • Largest large earthquake was in 1906 San Andreas fault (7.8MMS)
  • Can cause landslides which in turn may cause wildfires
65
Q

How do the characteristics of the Bay Area influence impacts of the seismic hazard?

A
  • costal, hilly and therefore prone to landslides (therefore floods)
  • soft sediment and loose gravels make it vulnerable is liquefaction
  • dense population that is ever growing making transport infrastructure most vulnerable
  • pockets of poverty are high at risk (minorities) as there are mostly poorly engineered buildings
  • rich often build homes on surrounding slopes which are well engineered hazard resistant buildings but are at high risk of landslides or wildfires
  • value of land makes land-use zoning hard, rent of sq ft is the second most expensive in the world, first in Tokyo
66
Q

How do politics and hazard perception influence the potential impacts to seismic hazards of the Bay Area?

A
  • Faulty hazard perception (denial of risk)
  • democrats dominate the local government
  • believe in government action
  • government is focused on public engagement to improve hazard response
  • however they are opposed to developments that will disrupt communities and heritage making land use zoning hard
67
Q

How does community response and management help influence the impacts of the hazard?

A
  • FEMA, California Governors Office and community groups are cooperating to produce the Bay Area Earthquake Plan (“safety depends on you reading the plans”)
  • Residents are taught to store supplies, have a family contact plan and “stop, cover, hold!” in the event of an earthquake
  • 4 task forces apart of the areas plan to rebuild Bay Area and return it back to normality including rehoming displaced residents and communications
68
Q

Where do tropical storms occur and why do they occur in these locations?

A
  • Sea temperature has to be above 27°c with and ocean depth of at least 70 m (need to have enough energy)
  • there needs to be convergence of air in the lower atmosphere (forces air to rise)
  • All winds move towards the equator (trade winds)
  • High pressure systems are always trying to move to an area of low pressure
69
Q

How do tropical storms form and why are they so powerful?

A
  • ocean warms above 27°C, this causes warm moist air to rise and air pressure falls, the rising air cools and condenses to form clouds
  • condensation releases latent heat, this warms the air as it rises which will eventually cool and condense, releasing further latent heat - forms continuous upwards convection currents
  • warm moist air is drawn into the low pressure system from different directions causing wind
  • rising air rotates and the storm follows a spiral path due to the Coriolis force
70
Q

What is the DEGG model of Hurricane Katrina?

A

Hazard:

  • 280 km/ph wind speeds (5 on Saffir Simpson Scale)
  • 10 m storm surge
  • 380mm of rainfall in 12 hrs

Impact:

  • $200 billion in losses
  • 1242 deaths (0.3% of the New Orleans pop)
  • 1 million homeless (110 000 properties destroyed)

Place:

  • levees were built for protection but not prepared for them to break (complacent)
  • there was poor maintenance of levees as there was a low tax base
  • distrust of government due to history of neglect and slavery made the response to the evacuation poor
  • state of emergency wasn’t declared until 48 hrs before event (not enough time for evacuation)
  • lack of coordination meant emergency rescue and relief was delayed
71
Q

What is the DEGG model for Typhoon Haiyan (Philippines)?

A

Hazard:

  • 250 km/ph wind speed (category 5)
  • 6m storm surge
  • 300mm of rainfall in 12 hrs

Disaster:

  • $3 billion in losses
  • 6200 deaths
  • 2 million homeless (all properties destroyed)

Place:

  • cities on the coast and no extensive defences
  • rapidly industrialising and urbanising = 1/3 in poverty (rapid urbanisation hinders developments and land use planning and concentrates people in vulnerable areas)
  • lack of education to understand how to protect and respond
  • insufficient hazard management
  • local governments virtually collapsed as many officials were victims and violence broke out
72
Q

Evaluate the impacts of two recent tropical storms in contrasting areas of the world?

A
  • 2005 Hurricane Katrina has the greatest economic costs whereas 2013 Typhoon Haiyan had the biggest human cost
  • Hazard characteristics don’t best describe the difference as the hazards where very similar, however Katrina was a slightly worse hazards but despite Haiyan being less hazardous killed more people
  • Characteristics of the people and place best explain the difference, both cities were low lying but the capacity to cope was the defining point (more of Tacloban’s population was vulnerable and FEMA failed to strengthen the levees but still saved most the city’s population, despite response was extremely flawed)
  • In conclusion Typhoon Haiyan had the most devastating impacts as compared to New Orleans, despite the flawed response and it being a more dangerous hazard
73
Q

Evaluate risk management designed to reduce the impacts of tropical storms

A

The most effective management is land use planning

  • prevents developments in vulnerable areas (e.g. in low lying areas, storm surges)
  • over time this will decrease risk of life and properly also after the event so life can quickly return to normality
  • however only useful in areas that have capacity to implement it, rapid urbanisation limits options (e.g. in Tacloban some areas have +2000 per km2)

Another effective management in hurricane forecasting and modelling

  • enable evacuation
  • allows for warning systems to be implemented and long term preparations
  • can go hand in hand with land use planning
  • as IT improves it will become more affordable, however for now isn’t an option for many countries as technology isn’t available
  • accurate predictions are hard
74
Q

Evaluate the role of adaptation in reducing impacts of storm hazards

A
  • Adaptation would reduce possible impacts of storms including loss of life and property (inc agricultural land destroyed, communications destroyed) from hazards such as storm surges or flooding
  • May lull a false sense of security, complacent and not obey evacuation order as they believe adaptation measures will protect them
  • Preparedness may be a better alternative, prevents people being complacent, includes: emergency services, evacuation plans and education
  • adaptation can’t be the role method to take