Hazard

This word originated from French languages as “Hasard” & as “Azzahr” in Arabic meaning ‘Chances’ or ‘Luck’. The result of hazard event involving injury or loss of human life, damage or loss of property, disruption of economic activity is termed as disaster.

A disaster occurs when a hazard impact on the vulnerable population & causes damage, casualty, & disruption. These disaster occur only when hazard & vulnerability meet.

Hazards are processes of the genesis of extreme events whereas disasters are the responses or results of hazards.

ðDefinition of Hazards:

Hazard is a situation, which has the potential to cause the disruption or damage to people, their services & their environment.

(i).Keith Smith:

According to Keith Smith, “Hazard is a naturally occurring or human induced process or event with the potential to create loss i.e., a general source of danger.”

(ii).Prof. Savindra Singh (2001):

According to Savindra Singh, “Hazards are generally taken to be the processes (Causal factor) & the respons (Results) of extreme events, both natural & anthropogenic, which cause an accident/extreme event/danger.”

ðCauses of Hazards:

The causes of hazards can be classified as follows:

(i).Natural Causes: 

Due to wind (Cyclone), water (flood), earth (earth quake, landslide) & fire (forest fire, biological pest attack & infection).

(ii).Man-made Causes:

These includes fuel, chemical & nuclear accident, brake down or disruption of information, communication or transportation systems on which community depends or sabotage.

ðCharacteristics of Hazards:

Hazards have the following characteristics features:

      i.         Hazards are natural or man-induced extreme events,

     ii.         Hazards are physical events or causes or processes of disasters,

   iii.         Hazards have potential for damaging different forms of life mainly human life,

   iv.         Hazards represent latent conditions for future threats to all types of biota,

     v.         Hazards are of varying origins; of natural origin or of anthropogenic origin,

   vi.         Hazards may or may not become disasters etc.

ðClassification of Hazards:

Mainly, hazards divided into three types, such as:

                                                                                       i.         Natural Hazard,

                                                                                      ii.         Quasi- Natural Hazard,

                                                                                    iii.         Anthropogenic Hazard.

(i).Natural Hazard:

A natural hazard is a natural phenomenon that might have a negative effect on human or the environment. Man have no role in natural hazard. It is fully caused by natural causes like, earthquake, volcanic eruption, cyclone, landslides, etc. Natural hazards are naturally caused either by rapid or slow onset events which can be-

a)     Geophysical: Earthquake, Landslides, Tsunamis & Volcanic Activity.

b)    Hydrological: Avalanches, Floods.

c)     Climatological: Extreme Temperatures, Drought & Wildfires.

d)    Meteorological: Cyclones, Storms or Wave Surges.

e)     Biological: Disease Epidemics, Insect or Animal Plagues.

Characteristics:

a)     It is purely natural process in the environment.

b)    A natural hazard is a natural phenomenon that might have a negative effect on human or the environment.

Example:

a)     Killer Sumatra tsunami of 26 December, 2004.

b)    Bhuj Earthquake (Gujarat, India) of 26 January, 2001.

c)     Super Cyclone of Orissa (India) in 1999.

d)    Hurricane Katrina (New Orleans, USA) in 2005.

(ii).Quasi-Natural Hazard:

At present, there is a lot of controversy among geologists, land scientists, environment scientists on the Quasi-Natural hazard. But without going into the debate, let’s get into the general discussion or give us an idea of the Quasi-Natural hazards.

Quasi-Natural hazards such as smog or desertification arise though the interaction of natural processes & human activities.

Quasi-Natural hazard is a situation which the origin is natural & man-made. For example, Landslide or floods are not happening today only for natural reasons or only for man-made reasons.

 (iii).Anthropogenic Hazard:

As the population increases, people are now living on steep hills, rivers & in deep forest for food, clothinf & shelter. Disasters are arising for their unscientific activity, unconsciousness. Which is why today a large number of people are directly involved. Anthropogenic hazards is the results of man-made causes.

Man-made hazards such as toxicity of pesticides to fauna, accidental release of chemicals or radiation from a nuclear plant. These are directly as a result of human activities.

Example:

a)     Bhopal Gas Tragedy on Dec. 2-3, 1984 (India).

b)    Chernobyl Nuclear Disaster (Ukraine), 1986. 

ðNatural Hazards & Human Intervention:

Although humans can do little or nothing to change the incidence or intensity of most natural phenomena, they have an important role to play in ensuring that natural events are not converted into disasters by their own actions. 

It is important to understand that 

a)     Human intervention can increase the frequency and severity of natural hazards.
For example, when the toe of a landslide is removed to make room for a settlement, the earth can move again and bury the settlement. 

b)    Human intervention may also cause natural hazards where none existed before.
Volcanoes erupt periodically, but it is not until the rich soils formed on their eject are occupied by farms and human settlements that they are considered hazardous. 


c)     Human intervention reduces the mitigating effect of natural ecosystems. 
Destruction of coral reefs, which removes the shore's first line of defense against ocean currents and storm surges, is a clear example of an intervention that diminishes the ability of an ecosystem to protect itself. An extreme case of destructive human intervention into an ecosystem is desertification, which, by its very definition, is a human-induced "natural" hazard. Quasi-natural and na-tech are terms used to denote such hybrids. 


ðImpacts of Hazard:

Physical Impact:

a)     Death of People.

b)    Destruction & loss of vital infrastructure like transport system, roads, bridges, power, lines & communication lines.

Economic Impact:

a)     Loss of job due to displacement.

b)    Loss of harvest & livestock.

Environment Impact:

a)     Loss of forest due to forest fire.

b)    Loss of fresh water due to salination.

c)     Disturbance of biodiversity.

d)    Loss of natural rivers & other tributaries.

Socio-economic Impact:

a)     Displacement of population.

b)    Loss of cultural identify.

ðManagement of Hazards:

Hazards can be managed very easily by taking many measures, like:

Forecast & Warning:

We need to be careful & predict the disaster before it happens. It is important to predict the time of each hazards. This forecast should give accurate estimates of the timing & severity of the incident. Forecast should be scientific. 

Evaluation:

The hazard assessment phase is divided into several steps & discussed. At first the observer sought to detect the environmental changes, than measured it with a disaster measure. Finally, after taking a look at the different types of actions of different types of rare species of animal, he decided. Technological approaches are especially used in disaster assessment.