& risk relationships

RISK

• The probability of a hazard event causing harmful consequences ( expected losses in terms of death, injuries, property damage,economy and environment).

Definition of risk

THE DISASTER RISK EQUATION

Risk [R] = HAZARD [H] X VULNERABILITY [V]

CAPACITY TO COPE [C]

The risk of a disaster increases as the frequency or severity of hazards increases, people’s vulnerability increases and people’s capacity to cope (ability to cope with the consequences) is decreased.

What factors tend to increase risk perception?

Factors increasing risk perception

• Involuntary hazard (Chernobyl)

• Immediate impact ( Cyclone Nargis)

• Direct impact ( Sichuan earthquake)

• Dreaded impact ( cancer)

• Many fatalities per disaster ( Katrina)

• Identifiable victims (Bhopal)

• Unfamiliar hazard ( tsunami 04)

• Lack belief in authority ( young pop)

• Media attention• Deaths grouped in

space & time (Bhuj)

What factors tend to reduce risk perception?

Factors which reduce risk perception

• Voluntary hazard ( mountaineers)

• Delayed impact ( Ethiopia 03,08)

• Common accident ( car crash)

• Few fatalities per disaster ( floods UK 07)

• Deaths random in space & time ( stomach cancer)

• Statistical victims ( cigarette smokers)

• Controllabel hazard ( ice on motorway)

• Familiar hazard ( river flooding)

• Belief in authority ( university scientist)

• Little media attention.• Indirect impact ( drought in

Spain & impact on tourism)

Factors which influence an Individual’s responses

• Experience• Material well being –

those who are better off have more choices.

• Personality – is the person a leader or a follower, a risk taker or minimiser?

Psychological denial of the risk

• Many people living in hazard prone areas, the risk many be known and understood, but is psychologically suppressed so that the benefits of living in an area are not challenged.

5 Most Dangerous U.S. Earthquake Hot Spots Beyond California

Cascadia Subduction Zone, this colliding land mass 50 miles offshore is capable of magnitude 9 earthquakes 30 times more powerful

Geological enigma in Missouri, that has produced some of the largest quakes on record for the US but has yet to be fully explained by scientists.

Running along the base of the Rocky Mountains, the 240-mile Wasatch Fault lies underneath Salt Lake City and the state’s urban corridor, home to 1.6 million people.

The 2nd largest earthquake ever recorded struck Alaska’s Prince William Sound in 64. The mag 9.2 quake killed 128 people, most by the resulting tsunami.

Hawaii - the islands are also susceptible to major earthquakes such as a mag 7.9 quake in 1868 that killed 77 people.

Reasons people may place themselves at risk

• Hazards are unpredictable.• Changing risks – sea levels rising,

deforestation leading to more frequent flash floods.

• Lack of alternatives.• People may weigh up the costs and benefits.• Perceptions of hazard risks tend to be

optimistic.

Risk assessment

• Likelihood of harm and damage.

Map of death

•High risk•High security e.g. California

•High risk•Low security e.g. Haiti, Bangladesh, Mali

•Low risk•High security e.g. UK

•Low risk•Low security e.g. Bolivia, Angola

Human vulnerability to disaster ( insecurity)Phys

ical

exp

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haz

ards

i.e.

risk

HUMAN FACTORS PHYSICAL FACTORS

Rapid population growth and urbanisation – this increases the number of people who are vulnerable to hazards,

especially in poor countries

Global warming – it’s thought to be increasing the number of hazards, e.g.

Floods and severe storms, which increases the number of disasters

Increasing world poverty – poor people are more vulnerable to hazards

El Nino events (oceanic current and temperature fluctuations) – these change global weather in an unpredictable way,

which makes hydro meteorological hazards more unpredictable

Exploitation of resources – e.g. Deforestation and los of wetlands can

lead to an increased risk of flooding and landslides

There are a number of factors why disasters are increasing:

Sources

• Geography for IB diploma by Nagle & Cooke• Natural Hazards & Disasters by Holmes &

Warn• Death map -

http://www.popsci.com/scitech/article/2008-12/map-death

• Five most dangerous hot spots - http://www.wired.com/wiredscience/2008/10/five-us-earthqu