Week 4

Question 1

what are the 4 patterns describing how people choose to respond to a risk?

Answer 1

absorb, accept, reduce, change

Question 2

describe the “absorb” pattern of how people choose to respond to a risk

Answer 2

view the risk as unproblematic or deny it outright

the probability is deemed too low to worry about

so, fate is determined by the capacity to absorb losses

Question 3

describe the “accept” pattern of how people choose to respond to a risk

Answer 3

there is awareness of the hazard (no denial)

passive attitude (there is little that can be done to reduce the impacts)

hazards are often viewed as acts of god

Question 4

describe the “reduce” pattern of how people choose to respond to a risk

Answer 4

there is awareness of the hazard (no denial)

action is taken to reduce impacts

typically, there is reactive response and some preparation

usually, people stay in place

e.g. flooding events, snow/wind related hazards

Question 5

describe the “change” pattern of how people choose to respond to a risk

Answer 5

there is awareness of the hazard (no denial)

radical action may be taken (move away or change the land use)

Question 6

what is an evocative hazard?

Answer 6

hazards that typically induce much public reaction despite data suggesting they may create little risk

Question 7

what is an example of an evocative hazard?

Answer 7

pesticides

pesticide use for law care has become an issue in many communities due to increasing awareness of “potential” impacts

Question 8

what are banal hazards?

Answer 8

hazards that induce little public reaction even tho they may have similar risks to some evocative hazards

Question 9

what is an example of a banal hazard?

Answer 9

peanut butter has an increased risk of cancer than pesticides

Question 10

in regards to risks, what is a transmitter?

Answer 10

generates and sends the message about the risk

Question 11

in regards to risks, what is a signal?

Answer 11

the message itself

Question 12

in regards to risks, what is a receiver?

Answer 12

target audience for message signals

the original signal may be considerably modified by the time it is received

Question 13

in regards to risks, what is a signal value?

Answer 13

signals can be prescribed values by the receiver

this may be related to the characteristics of the event and/or the hazard it reflects

high signal values may suggest that a new risk has appeared or that the risk is different than previously understood

e.g. a large accident that takes many lives may have a low signal value if it occurs as part of a familiar and understood system (such as a car crash)

a small accident in an unfamiliar or poorly understood system (such as a nuclear power plant) may have a high signal value and cause concern sign people may perceive the risk is uncontrollable

Question 14

what is stigmatization?

Answer 14

process by which negative images are ascribed to places, technologies, or people

the risk perception of a future event in the area could be altered simply because of past events there

Question 15

describe impacts

Answer 15

spread of impacts
— impacts can spread like ripples and often extend well beyond the local area
— even affecting entire countries, technologies (medications), industries (meat)

secondary impacts
— property values and insurance rates may change in response to an event

Question 16

what are the 5 different risk perception theories and what question do they attempt to answer?

Answer 16

knowledge, personality, economic, political, cultural

why do some people feel that some technologies (e.g. nuclear energy or pesticides) are a major concern while other people feel that they are not?

Question 17

describe the knowledge theory for risk perception. how was it tested?

Answer 17

greater knowledge of fatality data leads to a greater perceived threat from the technology

tested via educational level and self-reported knowledge

people were asked to provide an estimate of annual fatalities from 8 technologies (aviation, nuclear, energy, lawn mowers, etc.) their answers were then compared to actual fatality data

Question 18

describe the personality theory for risk perception. how was it tested?

Answer 18

there is consistency between personality type and the perceived threat from technological hazards

tested using validated measures and questionnaires developed by psychologists

Question 19

describe the economic theory for risk perception. how was it tested?

Answer 19

the wealthy are more willing to take risks with technology because they may benefit more or have better access

this theory is based on the annual income of the people tested

Question 20

describe the political theory for risk perception. how was it tested?

Answer 20

personal views toward risk are related to the political party (and policies) that the person supports

tested by determining the political ideology of the subjects thru the completion of a 20-question survey

Question 21

describe the cultural theory for risk perception. how was it tested?

Answer 21

the worldview (the way the person believes the world operates or should operate) is correlated to how the person perceives risk

the theory is based on the way of life of a person (urban, rural, retired, child-rearing, etc)

Question 22

define the hierarchical worldview

Answer 22

defines boundaries between superiors and subordinates

examples of this view:
— strong patriotism and support for country
— strong respect for authority (law, order, and obedience are strongly valued)
— strict ethical standards
— concern about lack of discipline in youth

Question 23

define the egalitarian worldview

Answer 23

centres on political solutions to inequality

examples of this view:
— belief that world conflict can be eliminated with a more equal distribution of resources
— support for government efforts to reduce poverty
— support high tax burdens on the wealthy
— a lack of trust in large corporations

Question 24

define the individualism worldview

Answer 24

emphasizes personal freedom and choice

examples of this view:
— constraints on the individuals should be minimized (lack of support for heavy government regulation)
— belief that a welfare state destroys individual initiative
— continued economic growth and private profit are keys to quality of life

Question 25

which of the 5 different risk perception theories proved to be conclusive?

Answer 25

personality, political, and cultural the cultural theory was found to be the best explanation for how people perceived the risk

Question 26

describe the results for the personality theory of risk perception

Answer 26

those who perceived technological activities as high risk had less aggressive personality types people with less aggressive personalities generally tend to avoid potential risks

Question 27

describe the results for the political theory of risk perception

Answer 27

those who identified as left-wing were more likely to see the technological activities as threatening

Question 28

what is a landslide?

Answer 28

downslope movements of rock or sediment because of gravity movement is classified as rapid if it can be detected by eye

Question 29

what are the 4 variables used to classify landslides?

Answer 29

mechanism of movement type of material amount of water present speed of movement

Question 30

what are the 3 basic mechanisms of landslide movement?

Answer 30

fall, slide, flow -------- fall --- rock or sediment dropping off the face of a cliff slide --- downslope movement along a discrete ("straight") failure plane flow --- movement of particles semi-independently of one another, commonly with the aid of water

Question 31

what are the types of landslide?

Answer 31

rock fall, slump, creep

Question 32

what is a rock fall?

Answer 32

a type of landslide mass movement caused by a fall mechanism it involves rock rolling down a steep slope or falling thru the air

Question 33

what is a slump?

Answer 33

a type of landslide in this mass movement, the failure plane is curved upward

Question 34

what is a creep?

Answer 34

a type of landslide this mass movement is caused by a flow mechanism the speed of movement ranges from a few millimeters to a meter annually

Question 35

what are the forces acting on a slope (landslide)?

Answer 35

the stability of a slope is based on the balance between 2 types of forces driving force --- these move material downslope; they are based on the weight of the material from vegetation, water, etc. resisting force --- these oppose downslope movement; they are based on the shear strength of the material

Question 36

what is the factor of safety?

Answer 36

the ratio of resisting forces to driving forces factor of safety = RF/DF when the ratio is over 1, the slope is stable... but when the ratio is under 1, the slope is unstable if the factor of safety equals 1, resisting forces equal the driving forces the forces are determined by relationships among material type, slope and topography, climate, vegetation, and water

Question 37

what role does material type play in risk of landslides?

Answer 37

low consolidation and the presence of weakness of planes can increase the risk of landslides slumps are most common in unconsolidated sediment slumps are rotational mass movements as opposed to translational mass movements --- rotational: material falls along a curved surface --- translational: material falls along a discrete plane translational movements often occur where sediment overlay bedrock; the failure plane is generally at the boundary between the soil and the bedrock

Question 38

what role does slope play in risk of landslides?

Answer 38

the steeper the slope, the greater the driving force --- steepest slopes are associated with rock falls --- moderate slopes are associated with flows and slides --- gentle slopes are associated with creep

Question 39

what role does topography play in risk of landslides?

Answer 39

topographic relief = the height of a hill/mountain above the land around it dangerous landslides are more likely in areas of high relief! NOTE elevation = altitude = from sea level relief = distance between top and base

Question 40

differentiate between elevation and relief

Answer 40

elevation = altitude = from sea level relief = distance between top and base

Question 41

what role does climate play in risk of landslides?

Answer 41

the climate of an area influences the amount of water that infiltrates and erodes the soil in dry climates, vegetation is sparse, soil is thin, and bare rock is exposed in many areas rock falls are more likely in those areas in humid climates, soil is thick, and rock is generally covered with soil and vegetation thus, flows and creep are more likely in those areas

Question 42

what role does vegetation play in risk of landslides?

Answer 42

dense vegetation can slow surface erosion roots add strength and cohesion to the slope therefore, improper deforestation often increases the frequency of landslides

Question 43

what role does water play in risk of landslides?

Answer 43

water saturates soil increasing the likelihood of flows following prolonged periods of deep-water infiltration, slumps can develop water can also erode the base of slope therefore decreasing its resisting force

Question 44

what regions are more at risk for landslides?

Answer 44

any location with significant variation in topography is at risk

Question 45

describe the frank slide

Answer 45

it is canada's deadliest and most well-known landslide it occurred in Alberta it killed 76 people, dammed the crowsnest river creating a lake, and buried 5km of railway the exact cause of the landslide is unknown but glaciation, mining, and heavy snow are likely contributors

Question 46

describe the effects of landslides

Answer 46

can block railways and highways in isolated areas thus severely impacting travel as urban areas continue to expand, property damage will increase approximately 30 people are killed by landslides annually in North America --- they can result in the development of new habitats. if a landslide blocks a river from flowing, a lake will form creating a new aquatic ecosystem produces an increase of biodiversity landslides can carry sediments that contain valuable minerals which become concentrated at the base of a slope following an event

Question 47

how do humans increase the likelihood of landslides?

Answer 47

grading of land surfaces for new home and building construction can increase probability of slope failure deforestation and urbanization are currently the leading human causes for the increase in landslides a lack of surface vegetation and a lack of tree roots enhance soil erosion

Question 48

what is deforestation and how does it affect the risks of landslides?

Answer 48

clear-cutting and the construction of logging roads can cause landslides in geologically unstable areas a lack of surface vegetation and a lack of tree roots enhance soil erosion

Question 49

what is urbanization and how does it affect the risks of landslides?

Answer 49

modern engineering has allowed us to turn hilly slopes into flat land for construction slopes are destabilized when rock is moved, laws are watered, septic systems are installed, and buildings are constructed these can add weight to the slope increasing the driving force

Question 50

how can we minimize the landslide hazard? what are features indicative of a slope?

Answer 50

an important first step is recognizing where they are most likely to occurs feature indicative of unstable slopes include --- cracks on a hillside --- a recessed crest in a valley wall --- large boulders or talus at a cliff base --- tilted trees --- exposed bedrock --- an irregular land surface at a slope base talus = fragments of rock that have moved down a slope and accumulated at its base aerial photos are used to detect some of these features and then hazards and then hazard maps can be produced

Question 51

what is talus?

Answer 51

fragments of rock that have moved down a slope and accumulated at its base

Question 52

how can we prevent landslides?

Answer 52

complete prevention is impossible, but certain engineering practices can minimize the hazard drainage control --- the objective is to remove excess water from the soil with pipes and drains levelling the slope --- material from the upper slope can be moved to the slope base with modern technology slope supports --- examples of these include retaining walls, rock bolts, and rock screens

Question 53

how do landslide warning systems work?

Answer 53

tiltmeters are instruments used to detect movement along a slope some rock screens along highways and railways in western North America are linked to signal systems rain gauges on slopes can identify when precipitation threshold has been reached

Question 54

describe the perception of the landslide hazard

Answer 54

the relative infrequency of large landslides tend to reduce awareness of this hazard it is especially a concern where evidence of past events is not visible people continue to build in areas prone to landslides requires adjustments to minimize deaths and property damage

Question 55

how can we adjust to landslide hazards?

Answer 55

crucial to safely cite critical facilities (e.g. hospitals, schools, power plants) away from landslide-prone areas reducing water pressure thru good drainage is the best corrective measure against the hazard since this will decrease the driving force analyzing landslide hazard maps and avoiding the best purchase of a home in a hazardous area is the best way to reduce risk