Basic concept of disaster and disaster risk
Disaster
The term disaster owes its origin to the French word “Desastre” which is combination of two words ‘des’ meaning bad and 'aster’ meaning star.
Thus the term refers to ‘ Bad or evil star’
- a serious disruption in the functioning of the community or society causing wide spread material, economic, social or environmental losses which exceed the ability of the affected society to cope using its own resources.
- A result from the combination of hazard, vulnerability and insufficient capacity or measure to reduce the potential chances of risk
- Happens when a hazard impacts on the vulnerable population and causes damage, casualties and disruption,
- Occurs only when hazards and vulnerability meet.
- It is also to be noted that with greater capacity of individual/community and environment to face these disaster, the impact of a hazard reduces
- Three major components namely hazard, vulnerability and capacity.
Vulnerability
| Underlying causes | Dynamic pressure | Unsafe conditions |
|---|---|---|
| Limited access to resources | Lack of Institutions, education, training, skills | Dangerous location |
| Illness and disabilities | Population expansion | Dangerous building |
| Age/sex | Urbanization | Low income level |
| Poverty | Uncontrolled development | |
| Environmental degradation |
Hazard
| Trigger event |
|---|
| Earthquake |
| Tsunamis |
| Flood |
| Cyclones |
| Volcanic Eruptions |
| Drought |
| Landslide |
| War |
| Technological accident |
| Environmental pollution |
How do we consider a disaster?
Any hazard - flood, earthquake or cyclone which is a triggering event along with greater vulnerability (inadequate access to resources, sick and old people, lack of awareness, etc) would lead to disaster causing greater loss to life and property.
Hazard
A dangerous condition or event, that threat or have the potential for causing injury to life or damage to property or the environment
→ The word ‘Hazard’ owes its origin to the word ‘hasard’ in old French and ‘az-zahr’ in arabic meaning ‘chance or luck’
→ Can be grouped into two broad categories namely natural and manmade.
Natural Hazard
• Caused by a natural phenomena.
- Hazards with meteorological
- Geological
- Biological origin
- Cyclones
- Tsunamis
- Earthquake
- Volcanic Eruption
Man Made Hazard
• Hazards due to human negligence
- Industries
- Energy generation facilities
- explosions
- Leakage of Toxic wast
- Pollution
- Dam failure
- Wars or Civil strife
Types of Hazard
| Types | Hazards |
|---|---|
| Geological Hazard | Earthquake, Tsunami, Volcanic Eruption, Landslide, Dam burst, Mine Fire |
| Water & Climatic Hazards | Tropical cyclone, Tornado & Hurricane, Flood, Drought, Hailstorm, Cloudburst, Landslide, Heat & Cold wave, Snow Avalanche, Sea Erosion |
| Environmental Hazard | Environmental Pollutions, Deforestation, Desertification, Pest Infection. |
| Biological Hazard | Human/Animal Epidemics, Pest attacks, Food Poisoning, Weapons of Mass Destruction. |
| Chemical, Industrial and Nuclear Accidents | Chemical Disasters, Industrial Disaster, Oil spills/Fire, Nuclear |
| Accident Related | Transportation accident, Plane Crash, rural/urban fires, Bombing, Forest Fires, Building collapse, Electric Accident, Festival Related, Mine Flooding. |
Vulnerability
- The extent to which a community, structure, services or geographic area is likely to be damaged or disrupted by the impact of particular hazard, on account of their nature, construction and proximity to hazardous terrains or disaster prone area.
- Physical Vulnerability
- Notions of who and what may be damaged or destroyed by natural hazard such as earthquakes or flood.
- Based on the physical condition of people and element at risk, such as buildings, infrastructure and their proximity, location and nature of hazard.
- Relates to the technical capability of building and structures to resist the forces acting upon them during a hazard event.
- Socio-Economic Vulnerability
- The degree to which a population is affected by a hazard will not merely lie in the physical components of vulnerability but also on the socioeconomic conditions.
- Hazards are always prevalent, but the hazard becomes a disaster only when there is greater vulnerability and less of capacity to cope with it.
Capacity
- Resources, means and strengths which exist in households and communities. Which enable them to cope with, withstand, prepare for, prevent, mitigate or quickly recover from a disaster.
Formula for Disaster Risk
presented by Ward, 1999
- Disaster Risk = Hazard * Vulnerability/Manageability
- Manageability - The degree to which the community can intervene and manage a hazard in order to reduce its potential impact.
- Disaster risk = Hazard * Vulnerability/Capacity.