hazards Flashcards
1
Q
What are 3 types of hazards?
A
Hydrological
Geogphysical
Atmospheric
2
Q
What is the Park Model?
A
a disaster/ response curve that shows the deterioration of quality of life after a hazard
3
Q
What are the 4 stages of the Park Model?
A
Pre-disaster
Relief
Rehabilitation
Reconstruction
4
Q
Advantages / Disadvantages of Park Model
A
A: useful to compare hazard events
shows recovery phase
deepness reflects scale of event
D: level of normality different for each country
some countries dont go back to normality
5
Q
What are different perceptions of hazards
A
Adaptation, Domination and Fatalism
6
Q
What are the 4 stages of hazard management cycle?
A
Preperation
Response
Recovery
Mitigation
7
Q
What are the layers of the earth?
A
inner core
outer core
mantle
crust
8
Q
Who introduced the continental drift?
A
Alfred Wegner
9
Q
What is the theory of continental drift and its evidence?
A
All continents began as one big one called Pangea
jigsaw fit
fossil records
geology
10
Q
What are convection currents?
A
Movements in molten rock in magma that acta as a conveyer belt for plates
11
Q
What is ridge push?
A
magma rises, plates move apart
magma cools to form new plate material and causes plates to move apart from each other
12
Q
What is sea floor spreading?
A
a process in which tectonic plates split apart from each other causing magma to rise up
13
Q
What is the process of slab pull?
A
denser plate sinks back into mantle and rest of plate pulled with it
14
Q
What is a hotspot?
A
A small volcano caused by a magma plume
15
Q
What is a deep sea trench?
A
when denser oceanic plate subducts underneath less dense drust to form a ‘trench’
16
Q
Island arc formation
A
partial melting of a plate at a subduction zone (destructive)
17
Q
Young fold mountains formation
A
When two continental plates move towards each other accumulating sediment between them (destructive plate boundary)
18
Q
Rift valleys formation
A
when tectonic plates beneath the Earth’s surface move away from one another in opposite directions, causing a small valley (constructive plate boundary)
19
Q
Ocean ridge formation
A
When plates move away from each other, causing magma to move up and seperate these plates
20
Q
Deep sea trench formation
A
found on destructive plate boundary at the point where oceanic denser plate sinks into mantle (destructive)
21
Q
Magma plumes and their relationship to plate movement
A
Magma plumes are areas of hot, upwelling mantle
As oceanic volcanoes move away from the hot spot of their tectonic plate, they cool and subside, producing older island chains.
22
Q
What is positive feedback?
A
changes that take place amplifying impacts e.g enhanced greenhouse effect
23
Q
What is negative feedback?
A
system counteracting change e.g leeves
24
Q
What are the 3 types of magma?
A
Basaltic
Rhyolitic
Andesitic
25
Features of a shield volcano
-low viscosity
-high silica content
-lava flows far
-low height
26
Features of a composite volcano
-high viscosity
-low silica content
-ava flows short length
-high height
27
Describe information about the Mount Mayon eruption
13th Jan 2018
most active composite volcano in the Philippines
located in the Pacific Ring of Fire and on a destructive plate boundary
is surrounded by 9 towns
reached alert level 4
28
What are impacts and responses of the Mount Mayon eruption?
0 killed
64000 stayed in 58 evacuation centres
$3.4 million damage
10,000 farmers affected
Roads blocked due to landslides and ash fall
Some flights out of Legaspi were cancelled
Cash for work programme.
Hygiene packages for 50,000 families
Philippine Red Cross set up first-aid stations.
USAID gave $100,000. They constructed toilets, baths, hand washing stations.
29
Describe information about the Eyjafjallajökull eruption
erupted in 2010
located in Iceland
VEI 3
lies on Mid Atlantic Ridge
very fine ash and a persistent eruption lasting 39 days
30
What are impacts and responses of the Eyjafjallajökull eruption?
airlines lost £130m per day
Kenya lost $1.3 million due to loss of crops becauyse of ash
People had to wear masks and eye cover
fresh food imports stopped - especially in Europe
area around volcano was evacuated
European Red Cross helped with food packages and helping families mostly affected
EU integrated air traffic management
31
What is pyroclastic flow? Give a named example location.
the mixture of hot rock fragments and gases moving at high speeds in a large cloud
Pompeii - the stone people caused by pyroclastic flow
1980 - Mt. St. Helens caused 600km2 of forestry to be destroyed.
32
What is tephra? Give a named example location.
ash fall varying from fine ash to large volcanic bombs
2010 eruption of Eyjafjallajökull led to the cancellation of 100,000 flights. Tephra also causes breathing difficulties for people with respiratory problems.
33
What is a lahar? Give a named example location.
Mixture of water that has melted from snow on top of mountain and rock fragments/volcanic ash
Armero in Colombia was overwhelmed by lahars from the Nevado del Ruiz volcanic eruption. Although located more than 20km away from the volcano, over 22,000 people were killed in the 8m deep lahars.
34
What are tsunamis? Give a named example location.
huge sea waves formed when a large volume of water is suddenly displaced above the sea level by vertical movements of the continental shelf.
1883 - eruption of Krakatoa resulted in volcanic tsunamis. 35 metre high waves destroyed 300 villages and islands. More than 36,000 people died as a result.
35
What is acid rain? Give a named example location.
The release of the toxic gas paired with rain can result in acid rain (contains a pH<4). Acid rain in Hawaii has caused farmers to lose crops in greenhouse gases.
36
Where are volcanoes usually distributed?
shield - constructive plates
composite - destructive plates
exceptions with the ring of fire and volcanoes formed from mantle plumes
37
What is VEI?
Volcanic Explosivity Index - a numeric scale that measures explosivity
38
How can volcanoes be prepared for?
monitoring volcanic activity
education of people
Evacuation procedures planned
training response teams
identifiying areas most at risk
39
How can volcanoes be mitigated?
concrete blocks to steer lava away from areas at risk
retrofitting structures at risk of mudflows
evacuation and exclusion zones
emergency aid and rescue ready
40
How can volcanoes be adapted to?
move away from areas at risk
discouraging tourism in that area
41
What are the 3 depths of an earthquake?
Shallow - 0-70km
Intermediate - 70-300km
Deep - 300-700km
42
What is an earthquake?
vibrations in the earth's crust that cause shaking at the surface
43
What is the epicentre?
the point of the earth's surface aligned with the earthquake origin
44
What is soil liquefaction?
when soils with high water content lose mechanical strength and act as a liquid
45
What are the hazards caused by earthquakes?
ground shaking
ground rupture
liquefaction
lan dslides
tsunamis
46
How can earthquakes be prepared for ?
monitoring seismic activity
education
earthquake drills e.g. Japan
47
How can earthquakes be mitigated for?
identifying areas most at risk
retrofitting structures
tsunami wave brake walls/ mangroves
48
How can earthquaked be adpated to?
moving away from area at risk
retrofiiting structures
49
Describe information about the Nepal earthquake
25th April 2015
7.8 magnitude
Onyl 8km deep
Located in south asia
50
What are impacts and responses of the Nepal earthquake?
9,000 died
22,000 injured
600,000 buildings destroyed
3 million people left homeless
1 million children could not return to school for at least a month
50% people still living in temporary shelters 2 years later
$1billion received in aid
Search and rescue teams from the UK, India and China
$200 million in aid from the Asian Development Bank
51
Describe information about the Christchurch earthquake
22nd Feb 2011
6.3 on Ritcher Scale
4.99km deep
lasted 10 seconds
52
What are impacts and responses of the Christchurch earthquake?
185 people killed
3129 people injured
100,000 properties were damaged,
$28 billion damage
water and sewage pipes were damaged
liquefaction destroyed many road and buildings
Five Rugby World Cup matches were cancelled
$6-7 million of international aid provided
300 Australian police officers flew into Christchurch
construction of around 10,000 affordable homes
30,000 residents were provided with chemical toilets
53
Describe information about the Boxing Day earthquake
Boxing Day 2004
magnitude 9.1
located on Sunda Megathrust fault
30m wave
Mangroves removed caused greater impact
54
What are impacts and responses of the Boxing Day earthquake?
228,000 dead
diseases spread fast e.g Cholera
saltwater made land infertile
fishermen lost all equipment
12 countries impacted
$14 billion provided in aid
Tsunami warning system implemented in response
US provided aircraft for Search and Rescue, surveying, and transport of aid cargo
55
How can effects of seismic activity be reduced?
preperation
mitigation
adaptation
prevention
56
What is viscousity?
A measure of a fluid’s resistance to flow
57
What are 3 types of volcanoes?
Active
Dormant
Extinct
58
What are the conditions needed for a tropical storm to form?
-oceans at 27 degrees
-70m of ocean depth
- 5 degrees N and S of the equator
59
Describe the formation of a tropical storm
-form when water is at 27 degrees, 70m of ocean depth and 5 degreed N or S of equator
- water vapour rises, air cools and condenses forming thunder clouds
-thunder clouds group together forming low pressure vaccum - called the eye where it is clear and calm due to lack of evaporation
-eye walls form outside eye - the worst conditions (strongest low pressure)
-rain bands form on outer areas with more rain and wind
-as storm travels it spins due to coriolis effect, getting stronger with more time and heat energy
-loses energy when reaching land -losing its source (water and evaporation)
60
What is the scale that measures wind speed called?
Saffir-simpson hurricane wind scale
61
How can people prepare for storm hazards?
-hurricane drills
-education of people
-weather warnings
-cyclone shelters e.g Bangladesh
-replanting mangroves
-radars monitoring wind and rain activity
62
How can storm hazards be mitigated?
Hand books/ factsheets in Georgia-
placing valubles and documents in waterproof case
packing emergency kit
having an escape plan
covering windows with shutters/plywood
63
How can storm hazards be prevented?
They can't - attempts include:
blowing storm away with fans
cloud seeding
cooling ocean with icebergs
64
How can people adapt around storm hazards?
-land use planning identifying areas most at risk
-retrofitting structures
-flood barriers
65
Describe information about Typhoon Haiyan
- category 5
- 8th nov 2013, Philippines
- winds at 195mph
66
What are impacts and responses of Typhoon Haiyan?
Tacloban experienced a 5-metre storm surge
6,300 people died
29,000 people were injured
4.1 million people were made homeless
800,000-litre oil leak that contaminated fishing waters
televised warning to people to prepare and evacuate
1,200 evacuation centres were set up to help the homeless
1 million food packs and 250,000 litres of water were distributed within 2 weeks
cash for work programme
Oxfam replaced fishing boats
67
How can people prevent wildfires?
-spray water on and around house to prevent catching fire
-controlled burning
-spsread awareness on wildfires
68
How can the public prepare for wildfires?
-educate public on fire safety
-ensure an emergency plan is in place
69
How can people adapt to wildfires?
-use lightning detection
-use satellites to check ground temp
-make homes out of non flammable material
70
What does the fire triangle consist of ?
-oxygen
-heat source
-fuel
71
What are pyrophytic plants and what are their adaptations?
plants adapted to tolerate fire.
thick bark, tissue with a high moisture
content and underground storage structure
72
What are causes of wildfires?
arson
lightning
cigarettes
unattended campfires
volcanic eruptions
73
What are impacts of wildfires?
loss of life
evacuation
loss of property
loss of wildlife
increased food risk
release of toxic gas
74
What are the 3 types of wildfires?
Ground wildfires - burn on the ground only, often below the level of leaves
Surface wildfires - burn on the surface of the forest with flames reaching as high as 1.3 metres
Crown wildfires - occur in the tree tops and can spread exceptionally fast in the top of trees - most destructive
75
Describe information about a local scale case study?
Gili Islands-
island is only 2km wide
1,500 permanent residents
transport is by bikes, horse and carriage and motor boats between the islands
located on an island arc
destructive margin
island has no hospital
76
Describe the event at a local case study
located in Indonesia
7.0 earthquake
slow government response
tsunami warning which was later cancelled
77
What are impacts and responses of the Gili Islands earthquake?
Impacts
8 people died
30% buildings destroyed
Horses ran loose
Looting
Tourism fell from 3,000 a day to 900 a day
Responses
Many people camped outside due to fear of falling buildings
Thousands of tourists left stranded for days
Indonesian Gov responded slowly due to the isolation of the islands
Water bills agreed to be lowered long term to help locals recover
50% of hotels could not return to normal by Feb 2019
Roads would be paved to ensure infrastructure meets higher mitigation standards
78
Describe information about a wildfire case study?
summer of 2019/2020 - wildfire in Australia the size of Portugal
New South Wales most affected
Rainfall between January and August 2019 was the lowest on record
temperatures and wind speeds increased but humidity remained low - prime condition
79
What are impacts and responses of the Australia Wildfires?
Impacts
33 people killed (4 firefighters)
11 million hectares of forest burnt
2000 houses destroyed
500 aircraft used to spray water
Responses
2,700 firefighters working in just NSW
3,000 army, navy and air force assisting with search and rescue and clean-up efforts
$2 billion austrlian dollars in aid from prime minister
80
How are the Philippines an example of a multi-hazard zone?
located on a destructive plate boundary - 22 active volcanoes
30% of population live within 30km of a volcano
Pacific ocean- prone to tsunamis
typhoon belt - the Philippines has 20 per year
25% of the population are in poverty
don't have time to recover from one hazard when another one hits them again
81
Constructive plate boundary - movement, landforms, types of lava and volcano, associated hazards
movement away from each other
ridges formed
basaltic lava and shield volcanoes
volcanoes, earthquakes
82
Destructive plate boundary - movement, landforms, types of lava and volcano, associated hazards
movement towards each other, oceanic plate subducts
youg fold mountains, deep sea trench
andesitic/rhyolitic lava and conservative volcanoes
volcanoes, earthquakes,tsunamis
83
Conservative plate boundary - movement, landforms, types of lava and volcano, associated hazards
plates move past each other
no volcanoes form
earthquakes due to build up of pressure
can cause tsunamis
84
What are the different seismic waves?
rayleigh and love
