Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Geography MA > Hazardous Environments > Flashcards

Hazardous Environments Flashcards

1
Q

what is the definition of Adjustment?

A

Adjustment: changes designed to react to and cope with a situation, such as the threat posed by a hazard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the definition of an Earthquake?

A

a violent shaking of the Earth’s crust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the definition of Emergency aid?

A

help in the form of food, medical care, and temporary housing provided immediately after the occurrence of a natural disaster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the definition of an Epicentre?

A

the point on the Earth’s surface that is directly above the focus of an earthquake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the definition of a Hazard

A

an event which threatens the wellbeing of people and their property

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the definition of infrastructure?

A

Infrastructure: the transport networks and the electricity, water, sewage, and communication systems that are vital to people and their settlements and businesses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the definition of a Lahar

A

a flow of wet material (meltwater or rainwater mixed with volcanic ash & tephra) flowing down the side of a volcano’s slopes which can become a serious hazard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the definition of a natural disaster?

A

Natural disaster: a natural event or hazard causing damage and destruction to property, as well as personal injuries and death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the definition of a natural event?

A

Natural event: something happening in the physical environment, such as a storm, volcanic eruption, or earthquake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the definition of plate movement?

A

Plate movement: mainly the coming together and the moving apart of tectonic plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the definition of prediction?

A

Prediction: the forecasting of future events or changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is Degg’s model?

A

a model in geography that illustrates how a natural disaster occurs when a vulnerable population is exposed to a hazard. It is depicted as basically a Venn diagram. One circle it eh natural event e.g., earthquake or flood and the other circle is people and human activities. When these two cirlces overlap you get a possible disaster and natural hazard (the intersection)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the definition of a natural hazard?

A

an extreme natural event that has the capacity to cause damage to people and property

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

when is a natural environment deemed hazaradous?

A

only when it has an impact on people e.g., a hurricane is not hazardour in itself, only if people are involved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the definition of a disaster?

A

an occurence where larfe numbers of poeple are affected (10 or more deaths, 100 or more poeple affected or state emergency declared (EDMAT)). A disaster is a realisation of a hazard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

name all the types of hazards

A

meteorological, hydrological, climatological, geophysical (aswell as biological hazards like disease, technical hazards like manmade hazards)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is meteorological? name some hazards that fit into this type of hazard.

A

specific weather based events
e.g., hurricane, thunderstorm, general storms, tropical storm, tornado, lighting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is hydrological? name some hazards that fit into this type of hazard.

A

caused by water
e.g., floods (inc. flash floods, river flooding), storm surge, some forms of mass movements (inc mud slides, avalanches)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is climatological? name some hazards that fit into this type of hazard.

A

prolonged, long term climate hazards
e.g,. wildfires, drought, extreme heat or cold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is geophysical (tectonic)? name some hazards that fit into this type of hazard.

A

movement of the earth
e.g., tsunamis, volcanic eruptions, earthquakes, other forms of mass movement like land lides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the definition of a hazard risk?

A

the chance or probability of being affected by a natural event

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the definition of vulnerability?

A

the ability of a person or group to anticipate, cope with, and recover from the impact of a natural hazard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the definition of capacity to cope?

A

depends on the level of development and commitment to prediction, preparedness, and response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the disaster- risk equation

A

risk = (hazard x vulnerability) / capacity to cope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what contributes to hazard?

A

time of day/week, duration, magnitude and intensity of hazard (distance it covers and the impacts), geology of rocks and sediment, depth of focus (shallow=more destructive), multihazardous environment (affects ability to bound back), secondary hazards (tsunami, climate change etc), frequency, distance from epicentre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what contributes to vulnerability?

A

level of development, how well off an area is (fragile economy), population density, high dependency ratio (old to young), buildings on marginal land (susceptible to landslides), quality of infrastructure (e.g., lack of steel rods), rural/ urban, rapid urbanisation, geology of an area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what contributes to capacity to cope?

A

preparation (e.g., evacuation plan), prediciton and warning systems, relations with other governments to receive aid, wealth of government, allowing them to invest in response (defence mechanisms), response (mitigation and search and rescue teams), trade and accesibility (location), governemnt stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

why can urbanisation serve as an agent of disaster?

A
  1. urbanisation can replace dispersed rural populations with cities which are a foci (centre of interest) for population, industry, and other institutions. this can cause an over-concentration of people and value. this increases succeptibility to catastrophic loss if a major population experiences a disaster. This is particularly acute in developing countries which might have 1-2 leading cities dominating. e.g., Lina has 40% of urban population and 70% of Peru’s industry in comparison to london with 15% of UK GDP and 15% of population
  2. urbanisation can lead to overcrowding, making safe evacuation more difficult and people being in poor housing conditions. it can also encourage development on marginal areas (e.g., unstable slopes - bogota, rio. or lowlying areas susceptible to tsunamis)
  3. susceptibility to disruption increases as sophisticated, complex transport networs exist
  4. poeple are more likely to expect a top down approach where civic authroities protect them from disasters or think they are safer in a big city - lack of awareness
  5. uneven replacement of buildings and infrastructure produces a patchwork of insability
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

name 3 didaste hotspots

A

mumbai, mozambique, san fransisco

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the definition of a tropical storm? what is always initially an example of a tropical storm?

A

a tropical storm is a low pressure system which has sustained high winds and torrential rains.
all hurricanes are examples of tropical storms, but they become reclassified as a hurricane one the wind speed exceeds (74 mph). Tropical storms are aka typhoons, or cyclones dependign on which part of the world theyre in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

describe the global ditribution of tropical storms

A

most tropical storms lie on either side of the equator. mostly above the tropic of Capricorn and below the Tropic of Cancer, within the tropics.
(5-25 degrees latitude)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what conditions are needed for a tropical storm to form?

A
  1. a deep layer of humid, warm, and unstable air (27 DEGREES CELCIUS) (+ deep warm water e.g., around 60 metres)
  2. a supply of energy (heat and moisture) from the sea
  3. a circulatory motion in the air (anticlockwise in the N hemisphere) encouraged by the CORIOLIS EFFECT. there are no hurricaned ont he equator and increases towards the tropics
  4. wind sheer needs to be low (small changes in wind speed and direction - vertical) -> (wind speed and direction with increasing altitude changes encourages the circulatory withing the cyclone)
  5. converging trade winds that force the air to rise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

describe the order in which a tropical storm forms

A
  1. tropical storms start when strong clusters of thunderstorms drift over warm ocean waters
  2. the very warm air from the storm and the ocean surface begin to rise - creating low pressure at the surface
  3. air rises faster and faster to fill this low pressure, in turn drawing more warm air off the sea and sucking coolder, drier air downwards
  4. the air spirals (due to coriolis force) cools and condenses as it rises which forms massive walls of cumulonimbus clouds aound the centre of the storm
  5. the condensation releases huge amounts of heat energy, which powers the storm and increases wind speeds
  6. cikder air sinks down through the centre of the tropicsl storm to form the eye. In the eye of the tropical storm the conditions are cals
  7. when the tropical storm reaches lands - and its source of heat energy and moisture disappears - it rapidly decreases in strength
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

draw out what the pressure, wind speed, rainfall and storm surge woudl look like as a side profile of the tropical storm. give reasoning

A

compare with booklet: 2. what are the causes and impacts of tropical cyclones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what hazards are associated with cyclones?

A

storm surges cuaing immense damage to coastal areas and floods inland,
strong winds that can tear roofs off, break windows, destroy crops, buildings, transport links, power supplies and communications,
torrential rain leading to flooding inland, often triggering landslides, mudslides, and flash flooding. this rain is caused by the warm humid air from cyclones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what is the definition of a storm surge?

A

a sudden, localised rise in sea level associated with low pressure and wind, allowing the sea to expands and the level of the sea to rise. It splits into two components:
pressure driven - low pressure sucks up the surface oft he ocean
wind driven - puches water towards the coast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

give a located example of a tropical storm. when and where was it?

A

Typhoon Haiyan. November 2013. Pacific Ocean, southwest of the Philippines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

give a located example of a tropical storm. when and where was it? give some statistics. what where the short and long term impacts?

A

Typhoon Haiyan. November 2013. Pacific Ocean, southwest of the Philippines.
the storm surge was 15 m tall, the wind speed was 314 km/h.
short term impacts:
1. destruction of infrastructure, roads, communications, including the airport from the storm surge
2. 5 million people lost their homes
3. 90% buildings destroyed in tacloban city from strong wind and flooding
4. no safe shelter, water for many
5. 5,500-10,000 died
5. economic - disruption and detruction of businesses and transport links. + social, physical, environmental
long term impacts:
1. destruciton fo roads etc. makes aid harder to receive (by nov only 20% of those requiring supplies and aid had recieved it)
2. looting made worse by only 100/1300 police reporting for duty. charity trucks were attakced and items including 33,000 large bags of rice were stolen
3. UN staff pulled out for safety reasons making getting air harder
(these might alos be short term (above))
4. no shelter and safe access to water days after
5. loss of infrastrucute
6. long term economic impacts -> $8 billion total damage inc. debt and money spent on recovery
7. displaced, homelessness, poverty due to loss of income

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

how are tropical storms measured?

A

using the saffir simposon scale. it goes from tropical depression-> tropical storm -> 1-5.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what is a tropical depression? what is a tropical storm? what is a hurricane? how are they differentiated?

A

a tropical cyclone in which the maximum sustained wind speed it 38 mph.
a tropical storm is a tropical cyclone in which the maximum sustained surface wind speen is 39mph-73mph.
a hurricane is a tropical cyclone equal to or exceeding 74mph.
WIND SPEED differentiates these tropicla cyclones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

which communitites might be most vulnerabel to hazards?

A

communities with lack of financing and resources, poorer isolated communities, communities with dependant poeple (disabled, ill, old), homeless (they have no healthcare), crowded areas (e.g., rapidly urbanised- meanigng they have less resources, harder to evacuate, loss of hub and business post hazard), groups persecuted by the state (repressed, ostrasiesed, may be pushed into marginalised land and less help form state), undoncumented migrants (no potential for help)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

how can communitites become more resilietn to natural disasters?

A

better response services (highger tech, better prepared), setting up systems, investing inn infrastructure, national wealth redistributed to help poorer less prepared communities, western europe helping E-Europe, change og government which actively invests in hazard resilience, city planning, knowledge, experiece

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

why is it important that the seas are warm for a tropical storm to form?

A

warm temp. is needed because it causes warm air to rise, CREATING A LOWE PRESSURE SURFACE, (as air moves up, it becomes less dense and therefore there’s lower pressure and more water evaporates)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

why do thick clouds and heavy rain form (tropical storms)?

A

the change in pressure because of the different temperatures causes thick clouds and causes air spirals (coriolis) to formwalls of clouds. the hot air rises and cold air falls causing a change in pressure. the hot air rises because it has lots of moisture, and as it rises it cools and the H2O condenses forming large clouds which are big and heavy causeing rain. The cold air which sinks forms the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what happens to the air when it reaches the top of the storm? why? (tropical storms)

A

it starts to circulate due to the coriolis effect. the air diverges at the top, away from the the rising air and centre. it then falls because the cooler air is denser. this cuases air spirals and forms clouds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what is the eye of the storm?

A

where there is calm in the middle and little win and rain because of all of the rising air that has so much energy. there is low pressure in the eye of the storm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

why does the hurricane lose energyh when it moves over land?

A

ther eis no more power supplied by the water and the source of hear energy and moisture dissappears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

why do hurricanes lose enrgy when they move further north or south?

A

because the temperature of the ocean decreases therefore there is less evaporation so the storm loses its source ofenergy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

why do we not experience tropical storms in the UK?

A

we don’t experience warm enough temperatures and we are not close enough to the equator to experience the coriolis effect. evaporation transfers energy from the serface tot he atmosphere. it temp increases then energy, and exaporation also increases but pressure decreases. low pressure means lots fo evaporation, and a stronger storm with more energy

50
Q

suggest reasons why disaster caused by floods and cyclones have increased more rapidly than for earthquakes

A

floods and cyclones have increases due to global warming and climate change, meaning thr weather is more dramatic

51
Q

describe the characteristics of the solid inner core.

A

very dense with a thickness of 1390km
it is magnetised
temp of 3000 degrees
solid

52
Q

describe the characteristics of the liquid outer core.

A

1380km thick
liquid
less dance than. solid inner core (11g/cm^3)
made of iron, nickel, small amount of lighter elements like silicon
lower than 3000 degrees

53
Q

describe the characteristics of the mantle.

A

larges mass of any of earths layers (70% of total mass)
made of magnesium-iron silicates and has a density of 3.35gcm^3
the outer part is called the LITHOSPHERE and it rigid and floats on the mobile ASTHENOSPHERE. it is a mixed state
it is like ‘plastic’ - if heares it can be moved

54
Q

describe the characteristics of the crust.

A

CONTINENTAL

cold rigid, thin layer, brittle
primarily granite
high content of aluminium and silica
around 35-70km thick and tensity of 2.8-9 gcm^3

OCEANIC CRUST

mainly basalt which is lower in silica byt higher in magnesium and iron.
it is thinner than continental crust
6-10m thick and 3gcm^3 density

55
Q

from inner to outer, name the layers of earth

A

solid inner core, liquid outer core, asthenosphere mantle, lithosphere mantle, continental and oceanic crust

56
Q

what is continental drift?

A

the idea that plates are slowly moving their position scross the earth’s surface over time. It explains the changing environments recorded in continental rocks

57
Q

why were the impacts of Typhoon Haiyan were so severe?

A
  • the scale -> the path took the hazard over the entire islnd, making the scale increase, therefore making it harder for aid workers to deliver aid and increasing severity
  • if it had hit mainland indonesia then thot he islands, it wouldn’t have been as bad
  • the fact that the philippines is a group of islands means it is more likely to experience a strong physical storm as the storm has mroe fuel
  • water was warmer, meaning they were more affecte by coriolis + more fuel form Pacific Ocean
  • Tacloban is densley populated, meaning more overcrowding, making evacuation more difficult, meanging it is more difficult to remove people
  • densley populated means more peopel in one area, meanign more business’ lsot and economic loss
  • economy fragile and quality of infrastructure made it more vulnerable becuase they are more liekyl to be destroyed and impacts worse.
58
Q

why do different plate boundaries create different hazards? (6)

A
  • constructive plate boundaries weakness’ in rocks allows magma to come up, causing volcanic hazards (due to magma)
  • in both detructive and C plate boundaries, magma is present and initially the plates move together due to slab pull and ridge push. as the plate rises up, causing volcanoes
  • destructive plate boundaries are more destrcutive because the rising magma contains gas which is higgly pressurised, making the eruption more explosive. Subduction means oceanic plate melts, creating magma
  • earthquakes are caused by collision and conservative plate boundaries, aswell as the two others mentioned. however, conservative is stronger due tot he pressure o the sudden plates moving + colission and constructive because they’re moving towards and against eachother meanign more pressure builds up and is released.
59
Q

what are the characteristics and impacts of earthquakes? what is it? what is it caused by? what is the centre called? what is the most powerful part called?

A

an earthquake is a sudden movement, or tremmor in the earth’s crust. it is caused by a release of pressure which causes a shock or seismic waves. Most earthquakes are found at plate boundaries, especially collision and destructive margins.
the centre of the earthquake underground is called the focus. THe most powerful part on the surface is called the epicentre. the cloer you are to this, the more damage occurs

60
Q

how are earthquakes measured?

A

with the richter scale. The strength is recorded on the seimograph

61
Q

what plays a big prt in the effect of the earthquake? why?

A

rock geology because it can amplify the waves

62
Q

what type of earthquakes are on constructive margins?

A

they are close to the surface, narrowly concentrated, magma created tremmors

63
Q

what type of earthquakes are on destructive margins?

A

broad belt of earthquakes, depth increasing with distance from the plate margin,-> earthquakes occur along the whole subduction zone, + shallow and deep earthquakes where plates converge,

64
Q

what type of earthquakes are on conservative margins?

A

narrow zone of usually shallow depth earthquakes

65
Q

list the factors affecting a physical hazard

A

geology - some ground types amplify shaking e.g., silt and mud
location of epicentre - e.g., tsunamis from underwater earthquakes
recent weather - wet/saturated is more likely to collapse or liquify
terrain - e.g., steep ground can affect mass movement
time of day

66
Q

list the factors affecting a (human) vulnerability

A
  • population density (more people affected)
  • building quality/ design (mor elikely to collapse)
  • distance from epicentre
  • warning and monitorring systems
  • wealth and money - do they have the ability to respond and protect people, do they have the ability to have good infrastructure
    -age
67
Q

what is the richter scale?

A

the scale is logorhythmic (each is 10x more powerful than the previous one). there are many more M1/2 than M9/10.
PROS:
it is an objective numerical recorded data making it easier to compare events against eachother
gives us a good indication of the magnitude of the physical hazards e.g., geology accounted for
CONS:
doesn’t accound for weakness of infrastructure and buildings, aswell as population densitry and vulnerability

68
Q

what is the mercalli scale?

A

it is a meausre of the damage i.e the eddects of the shaking on surface, buildings, and humans (intensity scale)
it is a descriptice scale which is qualitative and subjective
ranges from I-XII
PROS:
useful locally with an ordinary eyewitness
takes into account vulnerability and records damage
clear descriptiond for each threshold
CONS:
subjective
we can only use it in an area with people e.g., we can only use it in an area with people e.g., not in a super rural area/ underwater

69
Q

what are the hazards associated with an earthquake?

A
  • soil liquefaction - water saturated sediment loses cohesion due to shaking, causing sediment to lose bearing strength so buildings sink and topple
  • property damage, death - causes buildings to shake vigorously so they fall apart and collapse and collapsed buildings can injure people (near roads makes ir harder to access injured people) -> broken water and sewage pipelines mean no running water
  • mass movement - e.g, mudslides and avalanches cause destruction of land and destroys villages, roads, and isolates communities hampering relief
  • fires - earthquakes rupture gas pipes and breake electricity cables and destruction of property due to fires
  • tidal waves - e.g., underwater earthquakes makes the sea floor snap up, lifting a column of water. Gravity pulls the water down, fanning waves outwards. the individual waves stretch out and waves meet slope and shollow water. wavelenfth decreases, amplitude rrises. this causes buildings to be destroyed, flooding (disease, destruction of property, displacement), water damage
70
Q

name a located example of an earthquake. where was it? when was it? what magnitude was it on, on the richter scale?

A

Haiti, located in the Caribbean on the western part of the island of Hispaniola. It took place on the 12th January 2010. It measured at a 7 on the Richter scale, and a level 9 on the Mercalli scale. it had devastating impacts. the epicentre of the earthquake was 25km south of the capital

71
Q

what were the short-term impacts of the Haiti earthquake?

A

200,000 poeple killed
- 60% of the capital, Port-au-prince was destroyed
- 65km rupture in the E-PG fault and a 1.8 m slip
- 100 UN workers died
- buildings made aid harder to receive
- families fled to villages puttong more stain on them
- roads, comms, electricity, severely damaged hampering aid
- bodies were trapped - disease

72
Q

name some long term impacts of the Haiti earthquake

A
  • 230,000 deaths, 6900 of which were due to cholera
  • 500,000 cases of cholera form cholera epidemic
  • 1.5 million homeless
  • 60% infrastructure destroyed
  • 70% buildings collapsed
  • $8 billion in damages and losses
  • 4000 amputees
    -4000 prisoners escaped
    -20% jobs disappeared
  • by July 1910 98% rubble remained uncleaned and 1.6 million were in temporary camps
73
Q

how prepared was Haiti for an earthquake

A

-NOT as they were still recovering form earthquakes in 2008 x4, 2004, where 60% of harvests were destroyed and landslides
- the enquillo-plantain guardian fault hadn’t moved in the past 250 years so it was unexpected
- building destruction meant they needed help
- had limited infrastructure and health services and they didn’t have an emergency plan unlike Chile makng it difficult to cope
- lack of coordination na dlack of UN personell

74
Q

what type of response was there to the earthquake in Haiti?

A

borders opened with the Dominican Republic for those who needed hospitals available
- iceland had an emergency response team in Haiti within 24 hours
- over 1500 camps were set up all over Port-au-prince
- bad sanitation arrangement meant that encampments were full of excrement
- only 1 delivery a week of water , causing people to drink unfiltered water leading to cholera
- NGOs came however few spoke french

75
Q

why was Haiti vulnerable, why did it have a low capacity to cope?

A
  • it is poor - despite having 9.8 million people it only has a GNI of $660 per person per annum
  • high infant mortality, high HIV %, heavily dependant remittances sent from family members abroad (in 2008 it was worth 32 % of country’s GDP)
  • They had already been impacted from previous earthquakes and were recovering
  • only 2 % of land is forested (due to deforestation and charcoal manufacture) so it was more susceptible to landslides
  • Haiti sits on a set of complex plate margins
  • massive increase in capital due to rural urban migration so the impacts were felt deeply
  • many public services run by aid charities in the UN making it difficult to coordinate and respond
  • lack of disaster planning
76
Q

where are most volcanoes?

A

most are on convergent plate boundaries. most of these volcanoes are composite. (pacific)
most volcanoes are near the ocean because of the plates moving together that have to diff densities - DESTRUCTIVE (the oceanic crust subducts and melts creating magma)
some anomolies include the East african rift valley, iceland where the plates are constructive (allowing magma to rise as plates move apart) + more shield and fissure volcanoes
- some v in middle of ocean because there is a hotspot

77
Q

what drives volanism?

A

SUBDUCTION

78
Q

where are composite volcanoes found (which boundary?)? what shape are they? what ejecta type? explosivity? frequency? hazard? example?

A

Boundary- destructive
shape- steep sides (lava can’t flow far- alternating layers of lava and ash)
ejecta type- viscous, sticky (‘acidic’)
explosivity - violent, hardening rock blocks vents and builds pressure
frequency - rare
hazard- pyroclastic flows, lahars
e.g., Mt Fuji

79
Q

where are shield volcanoes found (which boundary?)? what shape are they? what ejecta type? explosivity? frequency? hazard? example?

A

Boundary- constructive
shape- gentle slope (lava can flow far)
ejecta type- thin, runny ‘basic’ lava
explosivity - effusive (non explosive), made of basalt and a few gases
frequency - frequent
hazard- gases and lava flows
e.g., Mauna Loa (Hawaii, USA)

80
Q

explain the formation of a hotspot volcano

A
  1. there is a localised area of the mantle which is particularly hot. this is a (mantle) plume of heat. (it melts crust and forms volcanoes)
  2. as the plate passes over the plume it starts to melt which is facilitated by the high heat and low pressure at the base of the lithosphere (plate)
  3. This melt, called magma, rises to form volcanoes
  4. as the plate moves away from the hotspot, the crust cools and becomes denser and sinks, resulting in the former volcanoes becoming denser and sinking, which results in the former volcano disappearing beneath the ocean surface to form underwater sea mounts
81
Q

what is the volcano explosivity index? what are its limitations

A

it measures the explosivity of eruptions based on the amount of material it ejects during the eruption. it is quantitative.
pro - objective (good way to measure size)
con- doesn’t take into account the length of eruption or type of material erupted

82
Q

outline the various different volcanic hazards

A

ash clouds, pyroclastic flows, lava flows, lahars, gas emission, tephra, geysers, wildfire, Jokulhaup which causes floods

83
Q

what are ash clouds? why is it a hazard?

A

An ash column rises into the atmosphere, spreads and as it calls can fall onto the ground.
hazard- can disrupt air travel as it is dangerous for aircraft engines, covers infrastructure, and can make it hard to breath (e.g., if you have asthma), difficult to clean up

84
Q

what are pyroclatic flows? why is it a hazard?

A

A pyroclastic flow is a dense, fast-moving flow of solidified lava pieces, volcanic ash, and hot gases. if it is denser than air it will flow downhill and is very fast and very very hot. it can be a flow of volcanic gases.
hazard- when it hits buildings it can destory them, burns/kills peopel and animals, can flow down river valleys and over topographical barriers

85
Q

what are lava flows? why is it a hazard?

A

more viscous lava is slower but if it less viscous it travels further, making it more hazardous
hazard- it can travel very far and any immovable infrastructure will be destroyed/buried under the flow

86
Q

what are lahars? why is it a hazard?

A

lahar is when tephra mixes with water and it produces deadly mud flows (lahars). this can be caused by hot ash mixed with ice/ rainfall and ash. They are fast and close to boiling temp.
hazard- they can bury infrastructure and risk of secondary lahar can be mixed with rainfall triggering mud flow

87
Q

what are gas emissions? why is it a hazard?

A

gases can build upt o dangerous levels in volcanoes in a limnic eruption ( CO2 and sulfur dioxide)
hazard- can suffocate/kill livestock

88
Q

what is tephra? why is it a hazard?

A

fragmented magma produced during the eruption. it includes ash, volcanic bombs, cinders
it is dangerous

89
Q

give a named example of a volcanic eruption. where was it? when was it?

A

Eyjafjallajökull volcano erupted in Iceland on 20th March 2010

90
Q

short term impacts of Iceland eruption 2010

A

by 15th April the ash plume began to affect Europe (as far as N Italy) e.g., flights were shut down for several days and over 100,000 air jounreys were cancelled as Iceland is under the jet stream and it pushed ash SE.
- water flowed into volcano, rapidly vaporising increasing its explosive power and it cooled very fast so glass rich ash was pushed into the atmosphere
possible:
volcanic ash, lava flow destroying buildings, gases from volcanoes, tephra falls having a local impact

91
Q

long term impacts of 2010 iceland eruption.

A

economic impact of £200million per day for airline industry
- affected other countries e.g., UK tourism lost £750 million in direct sales per day (0.5% UK’s tourism-related sales in 2010) in addition to an airline loss of £750 million (the UK also suffered form indirect losses of £450 million)
- Nissan plant in Japan has to stop the production of some models like the CUbe anand Murano SUV as they ran out of supply of critical sensors produced in Ireland
£450 million cost shows high value of air freight as 35% trade is air freight compared to 0.5% mass
- flower and fruit and veg production impacted in African countries e.g., Kenya, Zambia, GHana due to delays in transportation meaning large quantities were left to rot
e.g., $3 million in losses per day in Kenya and 1000+++ worker laid off temporarily
in total African countries lost 65$ million
- potential local contamination of water and crop failures

92
Q

was the severity of the outcome of the 2010 earthquake inevitable to Haiti? (8)

A

yes - vulnerable prior to earthquake where 60% harvests destroyed - capacity to cope, unexpected (first time in 250 years) - hindering capacity to prepare e.g., disaster planing and evacuation, only 2% of land forested to it was more susceptible to mudslides impacting access to water in villages, LiC - GNI is 660$ per person per annum limiting services and infrastructure, services run by charities impacting ability to repsond
no- if the magnitude had been lower, haiti received lots of aid worldwide e.g., Iceland emergency team in 24 hours however language barrier, half their debt was cancelled by world bank heping them rebuild in the long term

93
Q

analyse the short and long term impacts of volcanoes. (8)

A

short-term- lava flow, ash clouds, pyroclastic flow. pyroclastic flow is the flow of tephra - it destroys buildings due to force and heat and people can be killed. it also has an immediate cost and panic. lava can travel fast and far, having a higher impact so immovable infrastructure destroyed + farmland - economic impact. gas clouds because it can impact air travel e.g., 2010 iceland volcano.
Long term - economic impacts, housing & land. e.g., global supply affected and trade (2010 volcano). contamination of water local can be hard to clean up (from ash fall), and high conc of flouride which is harmful to animals. people are displaced and land + infrastructure destroyed. wider environmental impacts on wildlife as they threaten ecosystems. Tsunamis are another consequence btw
limitations - short term impacts also affected by level of develpment in area/may be limited by work of aid organisations or in more developed countries by widespread emergency services
LINK TO MAGNITUDE BY SAYING SHIELD VOLCANOES ARE MORE VULNERABLE TO VOLCANO FLOWS AND ARENT ON DESTRUCTIVE PLATE BOUNDARIES

94
Q

how does a seismometer (measuring seismic activity) help predict volcanic eruptions? pros and cons?

A

it is a cyclical machine which detects earthquakes and a swarm of earthquakes suggests that rising magma causes rock to shift (causing earthquakes and therefore volcanoes)
pros- you can use it to triangulate movement of earthquake and therefore magma
cons- premature evacuation and people might not take it as serious

95
Q

how does categorising volcanoes by level of activity help predict volcanic eruptions?

A

level of activity indicates likelihood of a volcano to explode

96
Q

how does measuring the volume of gas e.g., CO2 or SO2 help predict volcanic eruptions? pros and cons?

A

it shows explosivity when activity is spotted so teams can investigate further. If it increases it tells us that something has moved, therefore volcanic activity
con- monitoring equipment must be there which is difficult if it is remote

97
Q

how does ash and rock form previous eruptions help predict volcanic eruptions? pros and cons?

A

you can compare it to gauge the type and explosivity (chemistry of rock) aswell as seeing the distance it has travelled and tephra
pro- helps identify hazard
cons - associate with volcano, doesn’t help predict timing, assuming it will be the same scale

98
Q

how does change in shape (dome expansion) help predict volcanic eruptions? pros and cons?

A

by using tilt meters, you can see and compare that the magma reservoir below has inflated, causing the dome to inflate. this causes earthquakes because stressed rocks cause earthquakes.
pros - helps monitor and find where magma is rising from
cons - its location could be a false alarm, we are just inferring information (not certain)

99
Q

how does magma accumulation help predict volcanic eruptions? pros and cons?

A

build up of magma leads to volcanic eruptions sometimes.
cons- longer term and can be hard to predict when the actual eruption will happen

100
Q

why do people continue to live in areas which are at risk to natural hazards?

A
  • cheap geothermal energy can be generated from tectonic activity e.g., two-thirds of Iceland’s electricity E
  • people living in poverty have other things to think about on a daily basis e.g., food, money, security, family E/S
  • plate margins often coincide with favourable areas for settlement such as coastal areas where ports have developed E/En
  • soil near volcanoes is very fertile e.g., Naples area inc Mt Vesuvius for veg, grapes, other fruit, herbs E
  • housing can be cheaper in some areas E
  • relocating means moving away from families and friends and work S
  • communities have built up around volcanoes because of tourism potential e.g., warm bathing lakes, hot springs, geysers E
  • people may think there’s a low chance of anything actually happening
    -more effective monitoring and aqequate warnings so few are harmed S
  • people feel safe in buildings that are designed specifically S
  • valuable minerals such as tin, gold, diamonds are found near volcanoes to jobs are produced for mineral extraction
  • fault lines associated with water can allow water supplies to reach the surface, which is particularly important in desert regions
101
Q

how can we prepare for hazardous events? main points

A

remote sensing and GIS for prediction, building design and land use planning for prevention , and warning and evacuation for preparation

102
Q

how can remote sensing and GIS help prepare for earthquakes?

A
  • monitoring levels in water wells increases pressure increases, causing water to rise/ increase in tensions can cause more fractures so water levels fall
  • measuring ground uplift and tilting near features
  • rock ability to transmit electricity because the more water a rock holds, the better it can transmit electricity and the more fractures there are, the more water present
  • measure smaller earthquakes with a seismograph can predict larger earthquakes as it can be an aftershock, which can help prepare by giving a warning (however not WHEN) by monitoring wave activity
  • satellites can measure temp and ground deformation and can detect a large fault slip
    -measure gas emissions e.g., radon gas (detected in ground water) can mean earthquake as fractures release gas and it is an early indicator
  • where a few earthquakes have been, there will probably be more due to build-up (forecasting)
103
Q

what is remote sensing?

A

remote sensing of earth’s surface using satellites to provide data about changes in ground movement e.g., temp. change

104
Q

how can building design and land use planning help prepare for earthquakes?

A
  • foundation bolds tie the wall’s flexibility to foundations increasing strength
  • cross bracing
  • land use planning ensures there is open space to evacuate and ensures buildings aren’t built in at-risk areas
  • automatic shutters prevent glass from going everywhere
  • shear walls are made from banners that can shake without breaking - increases strength and reduces damage from earthquakes
  • shock absorbers, springs, wheels, ball bearings isolate buildings from the shaking grounds which prevents buildings from collapsing due to stress going to building reducing
  • buildings with reinforced concrete with networks of bar (steel bars within concrete) can stop the shaking causing the brittle concrete to fall
  • resistant water, gas, electrical mains (can be tilted with devices that automatically cut off to prevent fires) and water mains with flexible joints resist being damaged so water supply isnt cut off, minimising impacts
105
Q

how can warnings and evacuation help prepare for earthquakes?

A
  • emergency kits and grab bags
  • for mitigation
  • preparedness- training pupils in school and wider public and for families, schools, and factories, to have their own plan e.g., secure your space
  • evacuation plans reduce panic and ensures people are more likely to get help
  • can increase awareness
  • satellite imagery can help coordinate response e.g., on a city scale
  • if an alarm is raised, people can get to safety quickly e.g., under a desk or on a larger scale whole trains can stop reducing impact
  • seismic activity can give warning from seismic stations (with images)
  • seismic hazard mapping uses all data to show the areas of highest earthquake risk
  • having warning systems in place can allow people to hide
  • posters, signs, sirens to warn people
106
Q

give a named example of hazard mapping in a developed country. give some background details. what were some details about the hazard and its short-term impacts? relief, rehabilitation, reconstruction responses?

A

Tohuku earthquake and tsunami in Japan 2011
- 18,000, people died, 3 nuclear reactors at Fukushima power station were destroyed, and fear of radiation lead to 154,000 people from Fukushima, Iwate, Miyagi being evacuated
- Tsunami waves up to 40m high
- only 10 min evacuation time
- magnitude of 9 moment magnitude (Mw)
- chaotic response caused more damage than any possible contamination
- 1 worker dies from radiation
RRR:
- restrictions lifted in 2017, many havent returned e.g. young adults have settled elsewhere
- only 25% people have returned, of which are mainly elderly, due to perceptions and people’s trust in science being destroyed.
- conditions still seemed unsafe when gov lifted restrictions and withdrew compensation payments
bad - Okuma still had 50x the normal safety levels of radiation
- contamination of soil made areas uninhabitable
- in 2022, 1 million tonnes of contaminated water will be exceeded in storage and will have to be removed somehow
- depression is 2x above the national av and 2300 people died due to disruption of medical care/suicide
good-96% of planned works completed
- millions of tonnes of waste have been removed
- 400 km of new seawalls (2x as high as before)
- 2013 health report shows no radiation-related cases
- in 2017, a study found that in the worst affected area, life expectancy had only decreased by 3 months

107
Q

give a named example of hazard mapping in a developing country. give some background details. what were some details about the hazard and its short-term impacts? relief, rehabilitation, reconstruction responses?

A

Haiti 2010 earthquake. LiC and politically unstable. lack of urban planning causing Port-auPrince to be severely overpopulated and unregulated building standards. Lack of forestation led to flooding and landslides
-230,000 killed in Port-au-Prince
- damage caused is estimated to be 120% of Haiti’s GDP
- 1000s NGOs went to aid Haiti
- famine floods disease
- money was focused in short term relief not long term
- the interim Haiti recovery commission was responsible for aid projects and was disbanded in Nov 2011, only having spent less than half of the $4.6 billion budget, of which less than 10% went to the Gov directly and only 0.6% went to supporting Haitian businesses
RRR:
major crop losses (70% lost) in 2015-7 due to drought - worsened malnutrition
- 20% annual inflation worsened impacts and played a part in the president being assassinated
- squalid camps still exist, families have no running water, electricity,
- UN plan for humanitarian aid only raised a third of the money needed to support 4.2 million people
- no cholera reported since 2019 feb, showing medical system has widened

108
Q

name some short term responses that can reduce the impacts of earthquakes.

A

emergency aid (money), shelter, supplies

109
Q

name some forms of long term planning that can reduce the impacts of earthquakes.

A

risk assessment, hazard mapping, rebuilding programmes

110
Q

how can money/emergency aid reduce the impacts of an earthquake?

A

can help those in need and rehabilitation (+ rebuilding in long term). This is especially important in LiCs. It can also help fund basic needs for those affected + cleaning of roads. Aswell as funding search and rescues, temporary shelters, medical supplies and personell.

111
Q

what is emergency aid?

A

providing emergency resources, money, expertise, in the wake of a disaster

112
Q

how can shelter reduce the impacts of an earthquake?

A
  • help impacted families get to safety (from climate etc..)
  • helps get people out of danger, makes sure they have basic needs, can be a safety point/hub for relief efforts, gives access to services and prevents knock-on effects of earthquake, like illness
  • provides hygiene and sanitation (preventing long term health challenges
113
Q

how can supplies reduce the impacts of an earthquake?

A

mitigates its effects and provides immediate relief to those displaced e.g., food, water, (dehydration, starvation ,malnutrition) clothes, first aid
first aid can help those injured and prevent diseases that could arise and radios are useful for communications

114
Q

what does it mean to provide supplies?

A

providing emergency food, clean water

115
Q

how can risk assessments reduce the impacts of an earthquake?

A

-can identify vulnerable areas which need to be improved
- help inform people e.g., response units of where to go and public awareness
- can get aid to those who need it most

116
Q

what is a risk assessment?

A

assessing current state of situation and problems so that action can be taken to improve

117
Q

how can hazard mapping reduce the impacts of an earthquake?

A
  • identifies vulnerable areas and informs where to sned emergency services e.g., steep terrain, valleys, easily blocked streets, unstable terrain
  • helps coordinate response
  • identifies which areas need most ais, mitigating impacts
    post earthquake to coordinate personell
    (helps form risk mapping)
118
Q

how can rebuilding programs reduce the impacts of an earthquake?

A
  • informs people of which areas might not be ideal for living/where to construct shear walls, foundation bolts, etc..
    -can improve infrastructure which can improve impacts of earthquakes and resilience
  • improving infrastructure of buildings and bridges and roads can help save money and reduce severity of impacts
119
Q

what can lead to uneven development? (6) - not this topic pls move

A

core areas may have human and physical advantages- topography and environment can affect ability to build and develop, therefore impacting economic activity. Harder-to-access areas mean it is harder to get resources there and access to education and services may be worse e.g., amazon rainforest
- access to water can lead to uneven development because historically waterways have been used for transport and trade, improving economic activity

120
Q
A

Geography MA (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions