Physical Geography - Tectonic Processes & Hazards Flashcards

1
Q

L1 Describe the features of the crust

A
  • 7km-70km thick
  • Surface temp-400°C
  • Solid
  • Surface & body waves pass through
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2
Q

L1 Describe the features of the mantle

A
  • 700km-3000km
  • 870°C-3700°C (ductile)
  • Not very dense (roughly 4g/cm^3)
  • Phases of liquid & solid in layers
  • Body waves pass through at variable rates due to density changes
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3
Q

L1 Describe the features of the outer core

A
  • 3000km-5000km
  • 4400°C-6100°C
  • Dense (roughly 10g/cm^3)
  • 88% iron
  • Liquid (generates magnetic field)
  • Only P waves pass through
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4
Q

L1 Describe the features of the inner core

A
  • deeper than 5000km
  • 7000°C (radioactive decay)
  • Very dense (14g/cm^3)
  • Nickel & iron
  • Solid + radiates heat
  • Only P waves pass through
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5
Q

L2 What is mantle convection?

A

Heat produced by radioactive decay in the core heats the lower mantle, hot currents move in circles in the asthenosphere

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6
Q

L2 What is ridge push?

A

Elevated position of mid-ocean ridges causes oceanic lithosphere to slide down sides due to gravity

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7
Q

L2 What is slab pull?

A

Newly formed oceanic crust at mid-ocean ridges becomes denser & thicker as it cools - sinks into the mantle under own weight

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8
Q

L2 What is seafloor spreading?

A

Hot magma forced up from asthenosphere & hardens forming oceanic crust, crust pushes apart

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9
Q

L4 How do intra-plate earthquakes occur?

A

Ancient faults in the middle of plates, low mag., e.g. East African Rift Valley

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10
Q

L4 What scale do scientist use to measure earthquakes and what does it measure?

A

Moment Magnitude Scale - measures total energy released at the moment it occurs, uses size of the waves, amount of rock movement, area broken by the earthquake, resistance of the affected rocks

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11
Q

L4 How does the Moment Magnitude Scale work?

A

Logarithmic scale, goes from 1 (smallest) to generally around 10 (largest)

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12
Q

L4 What does the Mercalli scale do?

A

Takes observations from people who experienced the earthquake and rates them from I (hardly noticed) to XII (catastrophic)

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13
Q

L4 What kind of earthquakes occur at divergent boundaries?

A

Shallow focus, low mag. (5-6)

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14
Q

L4 What kind of earthquakes occur at convergent (o/c) boundaries?

A

range of focal depths, high mag. (8-9)

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15
Q

L4 What kind of earthquakes occur at convergent (o/o) boundaries?

A

range of focal depths, moderate to high mag. (7-9)

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16
Q

L4 What kind of earthquakes occur at convergent (c/c) boundaries?

A

shallow to moderate focal depths, moderate mag. (6-8)

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17
Q

L4 What kind of earthquakes occur at conservative boundaries?

A

shallow focus, moderate mag. (6-8)

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18
Q

L4 What is the Wadati-Benioff zone?

A

Where most pressure is built up and then released during an earthquake. Understanding its depth can help to understand how destructive an earthquake will be

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19
Q

L4 Describe primary waves

A

Arrives first, travels through crust, mantle, and core, longitudinal wave

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20
Q

L4 Describe secondary waves

A

Slower than p-waves, travels through crust and mantle, transverse wave

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21
Q

L4 Describe Rayleigh waves

A

Surface waves, rolling motion (up/down & side/side), responsible for most shaking

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22
Q

L4 Describe Love waves

A

Surface waves, fastest surface wave, moves side/side as it travels (zig zag pattern)

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23
Q

L5 Describe what liquefaction is and what damage it causes

A

Loosely packed, water-logged sediments near the ground’s surface which lose their strength due to strong ground shaking, it can cause flash flooding and the uprooting of infrastructure like pipes and manholes

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24
Q

L5 Explain how earthquakes can lead to mass movement and what damage it causes

A

Seismic waves shake the ground and cause slopes to destabilise and slip, can bury roads, towns, and infrastructure which makes rescuing those in affected areas difficult

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25
Q

L5 Summarise the Christchurch Earthquake Feb. 2011

A

6.3 mag. shallow focus earthquake, liquefaction was exaggerated because shockwaves of contrasting resonances occurred in the soft horizontal layers underground, 30m thick soft upper layer smacked into the solid layer beneath sending vibrations back to the surface

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26
Q

L5 What engineering was put in place in Christchurch after the 2011 earthquake to protect against the impacts of future events?

A

Cone Perimeter Testing (CPT) was carried out to assess the susceptibility of soil to liquefaction in different areas of Christchurch (quick and inexpensive but in some places boreholes were dug to explore deeper), new buildings built with stone columns (10m in ground), geogrid of plastic matting, and compacted gravel above to redistribute the weight of the building

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27
Q

L5 What is a tsunami and how is it caused?

A

A series of larger-than-normal waves which are usually caused by volcanic eruptions or underwater earthquakes

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28
Q

L5 Summarise the causes and impacts of the 2004 Boxing Day Tsunami

A

Caused by an earthquake off the coast of Sumatra, Indonesia that was 9.0-9.3 mag., thrust moved ocean floor 15m towards Indonesia

Coastal settlements were devastated (70% of residents killed in some villages, 1500 villages destroyed in Sumatra), much infrastructure was destroyed (Andaman & Nicobar cut off as jetties destroyed), economies devastated (60% of fishing fleet & industrial infrastructure destroyed in Sri Lanka, tourism industry lost £25m in Thailand - 120k jobs lost), ecosystems destroyed, vegetation & topsoil destroyed, freshwater supplies contaminated with seawater, $10bn total cost

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29
Q

L6 Where are volcanoes usually located? Give an example for each location

A

Along plate boundaries (e.g. Pacific Ring of Fire), at mid-ocean ridges (e.g. mid-Atlantic ridge), and at hotspots which can be in the centre of plates (e.g. Hawaii)

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30
Q

L6 How do plate boundaries influence what type of eruption occurs?

A

At divergent plate boundaries lava is usually basaltic so eruptions are less viscous and effusive (shield volcanoes). At convergent plate boundaries lava is usually andesitic or rhyolitic. This means the gas content is higher so the eruptions are more explosive (composite cone volcanoes)

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31
Q

L6 Summarise the features of a composite volcano. What is its alternative name? What types of lava does it contain?

A

Steep sides, high silica content - viscous lava, explosive, layers of solidified lava, found on destructive plate boundaries

Contains andesitic and rhyolitic lava

Also known as a strato volcano

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32
Q

L6 Summarise the features of a shield volcano. What type of lava does it contain?

A

Gently sloping sides, low silica content - less viscous lava, effusive, found on constructive plate boundaries and hot spots

Contains basaltic lava

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33
Q

L6 Describe the features of basaltic lava

A
  • Hottest type (1000-1200°C)
  • Low silica (50%)
  • Low gas content (0.5-2%)
  • Low viscosity
  • Effusive
  • Darker colour
  • Found at shield volcanoes
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34
Q

L6 Describe the features of andesitic lava

A
  • 800-1000°C
  • Intermediate silica (60%)
  • Intermediate gas content (3-4%)
  • Intermediate viscosity
  • Moderately explosive
  • Lighter colour
  • Found at composite volcanoes
  • Formed by the subducted oceanic plate melting
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35
Q

L6 Describe the features of rhyolitic lava

A
  • Coolest (650-800°C)
  • High silica (70%)
  • High gas content (4-6%)
  • High viscosity
  • Very violent, cataclysmic
  • Lighter volcano
  • Found at composite volcanoes (& supervolcanoes)
  • Formed by the subducted plate melting
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36
Q

L6 How do we measure the strength of volcanic eruptions? What is the scale based on? Describe what happens at levels 0, 2, 4, 6, 7, & 8

A

Volcanic Explosivity Index (VEI) - Logarithmic scale, it is based on the volume of erupted material, the height of the eruption, and the duration of the eruption

0 - gentle flow
2 - bi-weekly
4 - 1-2 yrs
6 - 50-100 yrs, largest in living memory -> global change in temperature (Pinatubo eruption, 1991 -0.5°C global temps)
7 - 500-1000 yrs (Mt. Tambora eruption, 1815, 0.5°C cooling, 90,000 deaths due to famine)
8 - every 50,000 yrs, super eruption, extinction level event

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37
Q

L6 What is a phreatomagmatic eruption?

A

When a volcano erupts through water/ice, this can cause large amounts of ash to be emitted

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38
Q

L7 Describe what lava flows are and if they are a primary or secondary hazard of volcanic eruptions

A

Very hot flows of molten rock, can take years to cool, generally not a threat to humans but destroy everything in its path - primary hazard

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39
Q

L7 Describe what pyroclastic flows are and if they are a primary or secondary hazard of volcanic eruptions

A

Dense hot rock, ash, and gases which move quickly across the Earth’s surface, very dangerous to humans - up to 100km/hr - primary hazard

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40
Q

L7 Describe what tephra and ash flows are and if they are a primary or secondary hazard of volcanic eruptions

A

Volcanic ash and rock that erupt from a volcano, larger pieces near the eruption can cause injuries/deaths, poor visibility & slippery roads, roofs collapse, engines become clogged (E15) - primary hazard

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41
Q

L7 Describe what gas eruptions are and if they are a primary or secondary hazard of volcanic eruptions

A

Magma contains dissolved gases - H2O, CO2, SO2, gases can travel thousands of km - primary hazard

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42
Q

L7 Describe what lahars are and if they are a primary or secondary hazard of volcanic eruptions

A

Mudflows that travel quickly down volcanoes, can’t outrun, when an eruption melts ice/snow or when rain mixes with ash - secondary hazard

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43
Q

L7 Describe what jökulhlaup are and if they are a primary or secondary hazard of volcanic eruptions

A

When heat from a volcanic eruption melts a glacier causing flooding - secondary hazard

44
Q

L8 What is the difference between a natural hazard and a natural disaster?

A

A natural hazard is an event such as an earthquake, volcano, or tsunami whereas a natural disaster is when a hazard effects a vulnerable population that can’t cope, usually leading to deaths and widespread poverty

45
Q

L8 What is the hazard risk equation?

A

Risk = (Hazard x Vulnerability)/Capacity

Where risk is the probability of harm/loss taking place, hazard is the type of disaster, time of day, mag., and duration, vulnerability is the ability to anticipate, cope, & recover, and capacity is the ability to protect lives from destruction & restoration of affected areas

46
Q

L8 Summarise the 2010 Haitian Earthquake (LIDC)

A

12th Jan 2010, magnitude 7.0 earthquake struck 24km from the capital

47
Q

L8 What were the physical factors that played a part in the devastation of Haiti in the 2010 earthquake? (LIDC)

A
  • Shallow focus (13km) - increased ground shaking
  • Liquefaction on loose soil - foundations of buildings sank
  • Epicentre 24km from Port-au-Prince - 2 million people (Haiti’s most densely populated city)
48
Q

L8 What political, social, and economic factors turned the 2010 Haiti earthquake into a disaster? (LIDC)

A
  • Developing country - poor, resources spent on immediate issues, like disease, rather than earthquake protection
  • High corruption - lack of commitment to improvement of infrastructure and living standards
  • Lack of building regulations - buildings poorly built, dense urban env. - difficult for rescue teams to work
  • Lack of disaster prep. - govt. officials and emergency services simply didn’t know what to do
  • Extreme poverty - didn’t have resources to cope with an earthquake
49
Q

L8 What were the impacts of the 2010 earthquake on Haiti? (LIDC)

A
  • Only 1 airport & limited ports/roads - prevented aid from arriving/being distributed fairly, led to more deaths
  • A quarter of govt. officials killed - lack of organisation for relief
  • Oct. 2010 Cholera outbreak - spread as a lack of medical professionals, by 2015 9000 had died
50
Q

L8 What was Haiti’s recovery effort like after the 2010 earthquake? (LIDC)

A
  • 13bn aid donated - however most remained with non-Haitian organisations & govts.
  • Concerns about corruption - organisations unwilling to give aid to the Haitian govt. - did it themselves, this prevented Haiti’s self-sufficiency as money did not go to local businesses/industries
  • Slow progress - by 2015 80,000 still lived in temporary housing/tents, cholera still ongoing
  • Some improvements however - new infrastructure, health stats increasing, govt. becoming more able to cope - issued a warning about 2013 Hurricane Sandy which saved lives, afterwards took a leading role in organising aid
51
Q

L9 Summarise the 2008 Chinese (Sichuan) Earthquake (EDC)

A

12th May 2008, intra-plate earthquake struck Sichuan, mag. 7.9, triggered landslides that led to a quarter of the deaths

52
Q

L9 Why was Sichuan vulnerable in 2008 earthquake? (EDC)

A
  • Poorly constructed buildings - corrupt govt. officials ignored building codes & accepted bribes to allow builders to take shortcuts
  • Damage was concentrated in rural areas and towns
53
Q

L9 What were the social & economic impacts of the 2008 Chinese (Sichuan) earthquake? (EDC)

A
  • 1000s of schools fell - 5300 children killed
  • 5m made homeless
  • 45m affected
  • However, China was a large country with a growing economy so had the money to pay for rescue and aid teams
54
Q

L9 Describe the responses to the 2008 Chinese (Sichuan) earthquake (EDC)

A

China’s strong central govt. was able to respond quickly and effectively:
- 130,000 soldiers & relief workers deployed within hours - some parachuted/hiked into mountains
- Medical services swiftly restored to prevent disease outbreaks
- Govt. pledge of $10bn for rebuilding, wrote off debt for those w/o insurance

55
Q

L9 What was the situation 2 years after the Chinese (Sichuan) earthquake? (EDC)

A
  • 97% of reconstruction projects were started
  • 99% of 196,000 farmhouses were rebuilt
  • 216 transport projects were ongoing/completed
56
Q

L9 Summarise the 2011 Japanese (Sendai) earthquake (AC)

A

11th March 2011, mag. 9.0 under Pacific, 100km East of Sendai (island of Honshu), seawater displacement caused a tsunami - 10m high, reached 10km inland

57
Q

L9 Why was Sendai vulnerable in 2011? (AC)

A
  • Located on East coast of Japan - frequent hazards
  • Nuclear power plant right on the coast - Fukushima, 47,000 evacuated, still a 20km exclusion zone today
58
Q

L9 What was Japan’s preparation like for the 2011 earthquake? (AC)

A
  • Good building construction - strict regulations (75% built w/ earthquakes in mind vs. 0% in Haiti), low levels of corruption
  • Well developed plans - vulnerable areas had walls, evac. shelters, & evac. routes, earthquake emergency kits in offices & homes, 1 min. early warning system, emergency drills in schools & businesses
59
Q

L9 What was Japan’s response to the 2011 earthquake? (AC)

A
  • Within 24hrs 110,000 troops were mobilised
  • All radio & TV stations switched to earthquake coverage
  • Bank of Japan offered $183bn to Japanese banks to protect the economy
  • Quickly accepted rescue & recovery teams from 20 countries (Haiti teams delayed by damage & bad coordination and China was not used to accepting international aid)
60
Q

L10 Summarise the 1995-97 Montserrat Volcanic Eruptions (LIDC)

A

18th July 1995, Soufriere Hills volcano in South, part of an island arc in the Caribbean Sea where the Atlantic plate subducts under the Caribbean plate (VEI 3-4), continued to erupt for years after 500 years of dormancy

61
Q

L10 Why was Montserrat vulnerable to the 1995-97 eruptions? (LIDC)

A
  • Pop. of 11,000 dropped to 4000 by ‘97, capital Plymouth located right at the bottom of volcano
  • 20% of GDP relied on tourism, also agriculture ($10m banana exports annually in ‘95)
  • 70-80% of forests were within range
62
Q

L10 What were the social and economic impacts of the 1995-97 Montserrat eruptions? (LIDC)

A
  • Dozens lost lives, 7000 moved away
  • Plymouth destroyed - govt. buildings & hospitals
  • 2/3rds houses and 3/4s of infrastructure destroyed
  • Unemployment rose as tourism collapsed
  • Top heavy pop. pyramid - young people saw no economic future so left older residents behind
63
Q

L10 What was the response to the 1995-97 Montserrat eruptions? (LIDC)

A
  • Southern part of the island closed off - still uninhabitable
  • Volcanic observatory built to monitor the volcano
  • New infrastructure built in safer northern part e.g. roads & an airport
64
Q

L10 Summarise the 1991 Mt. Pinatubo, Philippines eruption (EDC)

A

15th June 1991, Luzon, Philippines, catastrophic eruption creating ash, pyroclastic flows, and releasing gases into the atmosphere, released 10 cubic kms of magma (VEI 6)

65
Q

L10 Why was the Philippines vulnerable to the 1991 eruption? (EDC)

A
  • 200,000 people lived within 30km of the volcano (45% in poverty), unprepared as dormant for 500 years
  • Economy relied on agriculture and US spending from Clark Air Base (experienced $1bn damage)
  • Widespread deforestation increased risk for lahars - killed 300
66
Q

L10 What were the social and economic impacts of the 1991 Mt. Pinatubo, Philippines eruption? (EDC)

A
  • 800,000 displaced, 200,000 of these evacuated immediately, 800 died, thousands injured
  • 20,000 cases of respiratory issues due to tephra - SO2 emissions caused roughly 0.5°C global cooling
  • 100,000 hectares of farmland destroyed ($430m in losses), GDP decreased by 0.7%
67
Q

L10 What was the response to the 1991 Mt. Pinatubo, Philippines eruption? (EDC)

A
  • 200,000 evacuated, evacuees resettled
  • Philippine govt. & military led efforts, aid from US military & UN
  • Attempts to remove ash from farmland and restore immigration
  • Programmes to address lahar risks & forest restoration
68
Q

L10 Summarise the 2010 E15 volcanic eruption in Iceland (AC)

A

March-June 2010 E15 volcano erupted under a glacier, causing massive amounts of ash to be released which blew across Europe, shutting down airports for days (VEI 3)

69
Q

L10 Why wasn’t Iceland vulnerable to the E15 volcanic eruption in 2010? (AC)

A
  • Residents have pre-prepared backpacks with a survival kit, alerts on phones, designated meeting points, volcanoes are scientifically monitored
  • However, Europe wasn’t prepared and so was vulnerable to large economic losses
70
Q

L10 What were the social and economic impacts of the 2010 E15 eruption? (AC)

A
  • 100,000 flights cancelled - 10m passengers stranded, airlines lost $1.7bn, 30% of global airline capacity was cut
  • European economy lost $5bn
  • Kenya’s economy 20% based on export of fruit & veg. to Europe, Kenyan businesses had to dump fresh produce (costing them $1.3m a day in revenue)
71
Q

L10 What was the response to the 2010 E15 eruption? What opportunities did it create? (AC)

A

SHORT TERM: 800 people evacuated, European airspace closed for days, emergency services responded quickly

LONG TERM: Improved monitoring, regulations, & economic support implemented

OPPORTUNITIES: Reduced CO2 emissions, more passengers on trains e.g. Eurostar, successful Icelandic tourism campaign (Inspired by Iceland)

72
Q

L11 What is an IGO and give an example

A

Intergovernmental organisation, e.g. EMDAT

73
Q

L11 What is EMDAT and list the criteria for an event to be included in its database

A

EMDAT - international disaster database

Criteria (Must include at least 1 of the following):
- 10 or more people killed
- 100 or more people affected
- Declaration of a state of emergency
- Call for international assistance

74
Q

L11 Why have reported natural disasters risen?

A
  • Improvements in monitoring & recording
  • Improvements in communications technology
  • Global pop. has increased from 1960 (3 billion) to now (over 8 billion), therefore more people live in hazardous space
  • More of the world covered in concrete/other impermeable surfaces, therefore flood risks have increased
75
Q

L11 What are the current trends for disasters?

A
  • No. of people being killed by disasters is decreasing due to warning systems, better building codes, and disaster preparedness
  • 1994-2013 - avg. no. of people dying was 3x higher in LIDCs (322 per event) than in ACs (105)
  • Financial costs rising, ’90s avg. $20bn per year, ’00s avg. $100bn per year
76
Q

L11 Why might data from a disaster not be completely accurate and reliable?

A
  • Immediate focus is on aid, not on collecting data
  • Methods, and therefore results, vary because no single organisation is responsible
  • Difficult to gather data from remote areas: the very areas that need the most help in disaster planning
77
Q

L12 What were the global impacts of the 1991 Mt. Pinatubo eruption?

A
  • Ash deposited as far away as Indian Ocean
  • $100m damage to aeroplanes to the west
  • SO2 aerosol cloud circumnavigated the world, causing a 0.6°C dip in global temperatures ‘91-‘93
78
Q

L12 What were the global impacts of the E15 eruption in 2010?

A
  • Ash blown across Europe
  • Economic loss roughly $3bn
  • Tourists stranded
  • Airlines lost $200m a day
  • Kenyan flowers & veg. rotted in UK warehouses (lost $2m a day)
79
Q

L12 What were the global impacts of the 2011 Sendai earthquake?

A
  • Germany phased out nuclear power, closing 17 reactors by 2022
  • Contaminated the Pacific seawater
  • Changed Earth’s wobble by 17cm & rate of spin by 1.8μm
80
Q

L12 What were the global impacts of the 2004 Boxing Day tsunami?

A

Fatalities from 46 countries due to tourism - Sweden & Germany worst affected with roughly 550 deaths each

81
Q

L13 What is a hydrometeorological hazard?

A

A natural hazard caused by climatic processes, e.g. droughts, floods, tropical storms

82
Q

L13 Why is the Philippines a multi-hazard zone?

A
  • Sits on a major convergent plate boundary
  • N&E coasts face Pacific Ocean
  • Lies within SE Asia’s typhoon belt - hit by 6 to 9 typhoons a year
  • Tropical monsoon climate - heavy annual rains
  • 22 active volcanoes, 30% pop. live within 30km of a volcano
  • Landslides common due to steep topography, deforestation, & rainfall
83
Q

L13 Why is the Philippines a vulnerable country?

A
  • Rapidly developing lower-middle income country, fast growing pop., rapid urbanisation, high pop. density
  • Many of the poor live in coastal areas
  • 25% of pop. live in poverty
84
Q

L13 What is an example of one hazard that caused multiple other hazards?

A

Philippines earthquake 2006:
- Killed 15, injured 100, damaged 800 buildings
- Generated a 3m high tsunami
- Triggered landslides that fell into a lake, causing flooding that washed away homes

85
Q

L14 Define prediction in relation to natural hazards

A

Specification that a hazard will or will not occur at a given location, time frame, or magnitude

86
Q

L14 Define forecasting in relation to natural hazards

A

Specification of the probability of a hazard occurring at a given location, time frame, or magnitude

87
Q

L14 Why are earthquakes so hard to predict?

A
  • Some fault lines are stronger/weaker than others
  • Rocks melt & release lubricating fluids
  • Drier rocks build up more pressure
  • Varying gravitational forces have an effect
88
Q

L14 What is the IOTWS?

A

Indian Ocean Tsunami Warning System - set up after the 2004 Indian Ocean Tsunami between affected countries

89
Q

L14 Can earthquakes be predicted? If so, how?

A
  • Earthquakes are very difficult to predict
  • Only high risk areas can be identified (risk forecasting) in areas that have experienced severe shaking or liquefaction
  • ‘Seismic gaps’ - can identify areas that are ‘overdue’ for an earthquake
90
Q

L14 How can volcanic eruptions be predicted?

A
  • Monitoring of SO2 levels
  • Infrasound - low frequencies, listening to the volcano
  • Tiltmeters & strain meters detect ‘bulging’ as magma rises
  • Monitoring equipment can measure levels of magma chambers
91
Q

L14 Can tsunamis be predicted? If so, how?

A
  • Tsunamis can be partly predicted - earthquake-induced tsunamis cannot be
  • Seismometers can detect earthquakes, DART (Deep Ocean Assessment & Reporting of Tsunamis) buoys measure water levels/pressure
  • When caused by volcanoes, landslides can be observed into the sea - buoys can again be used
92
Q

L15 Describe the four stages of the Hazard Management Cycle, starting from right after the event occurs

A

Response - Immediate help in the form of rescue, emergency aid, food, water & shelter

Recovery - Rebuilding infrastructure & services, rehabilitating injured people (mentally & physically)

Mitigation - Acting to reduce the scale of the next disaster - land-use zoning, hazard-resistant buildings

Preparation - Community education, resilience building, how to act before, during, & after, prediction, warning, and evacuation plans

93
Q

L15 How does Park’s model show the disaster management cycle with three curves?

A
  • Curve A shows a disaster with a relatively small impact - QoL improves quickly & returns to normal in a few months
  • Curve B shows a disaster with a bigger QoL impact & reconstruction takes longer, mitigation improves QoL to higher than before, community is better prepared
  • Curve C shows a disaster with a major QoL impact with a slow reconstruction phase, years later QoL has not returned to pre-disaster levels, e.g. 2010 Haiti
94
Q

L16 What are the different categories of disaster management plans?

A
  • Modifying the event - mitigating impacts by reducing areal extent/magnitude (before-hand, long-term)
  • Modifying vulnerability - remove people, help them cope by building resilience (before-hand, short-term)
  • Modifying the loss - aid recovery & reconstruction (after event, short/long-term)
95
Q

L16 How can disaster management strategies be further classed as?

A
  • Mitigation - actions that a community takes to reduce vulnerability in advance
  • Adaptation - ways in which communities can live with hazards, reducing risks
96
Q

L16 What two ways can the scale of disaster management strategies be classed as?

A
  • Micro - strengthening individual buildings, people, or structures
  • Macro - large-scale protective measures designed to protect whole communities
97
Q

L17 Summarise the process of modifying vulnerabilities

A
  • Prediction & warning
  • Community preparedness
  • Education to change behaviour
98
Q

L17 How does high-tech monitoring help to aid the process of modifying vulnerabilities?

A
  • GIS - create hazard maps for management
  • Early warning systems - scientific instruments
  • Satellite-communication tech.
  • Mobile phone tech. - rapid warnings
99
Q

L17 How does crisis mapping help to aid the process of modifying vulnerabilities?

A
  • Crowdsourced info. - satellite info., maps, & models to accurately map areas
  • Pre-mapping vulnerable areas
  • e.g. Nepal 2015, volunteers w/ bicycles & GPS tracking went to remote villages to collect data
100
Q

L17 How does public education/community preparedness help to aid the process of modifying vulnerabilities?

A
  • Schools & offices have regular drills (Japan 4x a year)
  • Encourage households to make emergency kits, e.g. Vik residents
  • Effective educational materials about construction

Community preparedness:
- Creating a list of vulnerable people for special assistance
- Organising practise evacuation drills
- First aid courses

101
Q

L17 How have buildings been earthquake-proofed in Japan?

A

Two levels of resilience:
- 1st level - smaller earthquakes, experienced 3/4 times in its lifetime
- 2nd level - extreme earthquakes (>7.9 mag.)

  • Shock absorbers - absorb seismic energy, rubber blocks
  • Top-to-toe resilience - reduce motion with dampers at certain levels
  • Protective mesh - prevent the structure buckling
102
Q

L18 How do aid donors help to aid the process of modifying loss?

A
  • Provide emergency aid, short-term aid, and long-term aid
  • Aid provided as cash, personnel, services, or equipment and is distributed straight to the affected govt.
  • e.g. Haiti 2010 - Effort was controlled directly by aid agencies & foreign govts. because of the corruption of the Haitian govt.
103
Q

L18 How do NGOs help to aid the process of modifying loss?

A
  • Important where govts. are struggling to respond, provide funds, coordinate search & rescue, develop reconstruction plans
  • Aid is provided for free, helps to administer emergency, short, & long-term aid
  • e.g. 2005 Pakistan Earthquake:
  • 7.6 mag., 73,000 died (17,000 children)
  • NGOs provided 500,000 tents, 6m blankets, safe water for 700,000 as emergency
  • Short-term: more permanent shelters, water re-established
  • Long-term: schools & hospitals rebuilt, community disaster risk programmes made
104
Q

L18 How do insurance companies help to aid the process of modifying loss?

A
  • Provides individuals & businesses with money to rebuild
  • Coverage helps communities recover from disasters
  • In ACs, like Japan, govts. & insurance companies work together to provide insurance against economic losses - this is unaffordable in developing countries
  • 2011 - $54bn worldwide earthquake damage
105
Q

L18 How do communities help to aid the process of modifying loss?

A
  • Local people often first to respond & play crucial role a recovery
  • Search & rescue efforts, in remote/isolated communities it takes days/weeks for aid to arrive, local people help to recover, often involved in long-term strategies for rebuilding & resilience
  • e.g. Afghanistan 2015 - villagers in mountains travelled to more remote areas to help with search & rescue