Hazards: A level Geography

Concept of Hazard in Geographical Context

Physical Geography: Hazards

The concept of hazard

Volcanic Hazards

Seismic Hazards

Storm Hazards

Wildfires

5.1 Concept of Hazard in Geographical Context

A Hazard is something that's a potential threat to human life or property.

A natural hazard is a perceived event that threatens both life and property. They often result in disasters that cause some loss of life and or damage to the built environment and create severe disruption to human activities.

Natural Hazards are caused by natural processes and be divided into three types:

Geophysical hazards- Caused by Land Processes

These include earthquakes, volcanic eruptions, landslides and tsunamis

Atmospheric Hazards- Caused by Climatic Processes

These include tropical cyclones, storms, droughts, extremes of hot or cold weather and wildfires.

Hydrological Hazards- Caused by Water Movement

These include floods and avalanches

Disaster: When a hazard actually seriously affects humans

Risk: The Likelihood that humans will be seriously affected by a hazard.

Vulnerability: How susceptible a population is to the damage caused by a hazard

Hazards can have significant impacts while they are occurring, and often need and emergency response (eg. evacuating an area). The impacts can also go on for a long time after the hazard itself has passed.

Risk and Vulnerability:

Risk is the exposure of people to a hazardous event presenting a potential threat to themselves, their possessions and the built environment in which they live. People though, consciously put themselves at risk from natural hazards and the question has to be why do they do it?

Possible reasons include the following:

Hazard events are unpredictable: We cannot predict the frequency, magnitude or scale of a natural event.

Lack of alternatives: Due to social, political, economic and cultural factors, people cannot simply uproot themselves from one place and move to another, giving up their homes, land and employment.

Changing the level of risk: Places that were once relatively safe may have become, through time, far more of a risk. Deforestation, for example, could result in more flooding from torrential rain associated with tropical storms and there could also be a greater risk from landslides.

Cost/benefit: There are many hazardous areas that offer advantages that in people's minds outweigh the risk that they are taking. Californian cities, for example, have a high risk from earthquakes, but people see the many advantages of living there as greater than the potential risk.

Perception

Vulnerability to physical hazards means the potential for loss. Since losses vary geographically over time and among different social groups, vulnerability therefore also varies over time and space.

Risk is different to people in different areas. A similar sized natural hazard event can have widely varying impacts in different parts of the world. People's wealth and the level of technology that they can apply do affect the degree to which the hazard event will impact upon them.