THESE TERMS ARE OFTEN CONFUSED BUT THEY ARE QUITE DIFFERENT.

Perception, Risk and Vulnerability

Risk - the probability of a hazard occurring

Vulnerability - the susceptibility of a population or society to the impacts of a hazard

Perception - a population or individuals understanding of hazard risk

EARTHQUAKESEARTHQUAKES HURRICANE/CYCLONEHURRICANE/CYCLONE

Proximity to Plate Boundaries

Proximity to active fault line like San Andreas in USA (Frequency)

Living on soft ground that amplifies earthquake waves

Proximity to coastlines in earthquake zones (Tsunami risk)

Living in the tropicsLiving near

coastlines in the tropics

visiting the tropics during hurricane season

TIME (SEASON)TIME (SEASON) LOCATIONLOCATION

A bush fire is much more likely to occur during summer due to:

-higher average temperatures

-dry conditions and dry fuel-Electric storms more

frequent (lightning)-hot winds more frequent

EARTHQUAKESEARTHQUAKES HURRICANES/CYCLONESHURRICANES/CYCLONES

The risk of Earthquake along the North Anatolian Fault in Turkey is greater than along the San Andreas Fault line because earthquakes occur there more frequently.

Time is unlikely to be so important in earthquake events since time scales for earthquakes are large and sporadic and not dependent on season.

Strong seasonal influence due to insolation warming oceans to 26.5◦ and release of latent heat

Prevailing winds and distance of open ocean

Vulnerability

Knowledge about the Event

Education about Safe Procedures

Upkeep to the home

Access to Technology

Wealth

Time of the Event

State of Health

Clothing and Equipment

Emergency Services

Other People

Perception of Risk

Perception of the risk underlies a number of factors that result in higher vulnerability.

If people believe that “it will never happen to me” They might not:

-invest in safety equipment-seek knowledge of the event-bother to understand potential hazards or best

responseAcquire technology such as a radio, breathing

equipment or similar

Day or Night?Winter or Summer?Week day or Week-end?Rush hour or midday?This year or next year?In my lifetime or my childs?Time scales are important since we are often

more vulnerable at certain times. In 1993 an Earthquake struck Gujarat in India at

5am –many people were buried alive by collapsed homes while they slept. Two –three hours later and many more would have survived.

Other people can influence your vulnerability. For example:

-Someone in the street might be a firefighter-A neighbour might not cut back his trees

during fire season-A dilapidated building or leaning tree might

come down on to your property during a storm

-A neighbour might have a basement you can shelter in.

Sadly money to a certain extent controls the vulnerability of individuals and communities.

-Can the town afford the Cyclone shelter?-Can the family afford to put in a basement-Can the whole street afford to put in roof

sprinklers?-Can the city afford to train enough emergency

personnel?-Does the country have the means to supply

food and water?

The most vulnerable in hazard prone environments are the very young, the elderly, the sick and the invalids.

A simple injury such as a twisted ankle can affect your vulnerability

Temporary illnessOften vulnerable communities suffer from

secondary events. For example they survived the Flood, but became sick due to the spread of disease that followed (consumption of dirty water)

Radio and TV broadcast knowledge of the hazard, where it is, where it is heading, its intensity

Sources of light –most hazards cut electricityPower tools, useful for cutting and liftingCommunication devices such as phones,

internet and GPS may assist in last minute education and avoidance or help in response

Owning or having access to the ideal clothing or equipment can be critical for survival or reducing potential impact:

-Bushfire –Natural fabrics long sleeves and long pants –breathing apparatus, petrol

powered water pump, metal buckets-Flood –Warm clothing, torch, food, clean

water, boat/raft-Earthquake – Clean water, food, torch, spare

batteries, first aid box, portable gas cooking or camping gear, blankets.

Communities are less vulnerable if there are trained personnel who can:

-Organize evacuation-Treat injuries on site-Cut trapped people from wreckage-Free people buried under rubble-Transport key supplies such as food, water,

blankets to those effected-Give advice, broadcast information, reduce

panic

Some homes are more vulnerable than others. It does depend on the hazard of course

Earthquake –homes built illegally and not to building standards are vulnerable to collapse.

Bushfire –homes with overgrown gardens and overhanging trees more vulnerable than cleared gardens

Cyclone –homes that are not elevated in areas prone to tidal surge or homes without windows boarded up

Tornadoes –homes without basements

Education can save lives. Here are some examples:-Knowing to get under a table or stand in a doorway

during an earthquake-Knowing that the eye will be preceded by the

strongest winds and rainfall in a hurricane/cyclone-that fire travels uphill faster than downhill-Having a good bushfire plan-Tsunamis are preceded by rapid ocean withdrawal at

the beach –minutes to get to higher ground-Acquiring skills such as first aid, or bush survival

Education

Source:Image: Tsunami Warning, a Creative Commons Attribution Share-Alike (2.0) image from livenature's photostream

For a selected hazard/disaster (hurricane, earthquake or drought), compare the factors influencing vulnerability for an LEDC and an MEDC - as mentioned on the spider diagram on slide 6.

Explain why perception of risk of your chosen hazard is especially important and how individuals can ensure they are realistic in their perception.