A disaster may simply be termed as an event that entails the damage, loss and destruction of life and property at a catastrophic level. It is differentiated from a hazard on the basis of the intensity of loss to people, economic assets and structures. Thus, in simple terms, a disaster is a hazard of calamitous nature. This, in turn, is dependent on several factors such as geographical location, population, climate and the type of the earth surface/degree of vulnerability. The word disaster comes from astrology; when the stars are not aligned in a favourable position, a bad event is expected to occur. The word originates from the Middle French désastre, from Old Italian disastro and from the Greek pejorative prefix dis—bad + aster—star.
The main features of a disaster are:
Types of Disasters
Disasters may broadly be classified into two categories, natural disasters and man-made disasters. At times, one disaster triggers a secondary one; for instance, an earthquake in the ocean floor can cause a tsunami resulting in coastal flooding.
A natural disaster occurs when a natural hazard (volcanoes, earthquakes, tornadoes) interrupts human activities causing extensive damage to life and property. The loss caused by such an event is directly proportional to the inhabitation of that particular area. The density of population also affects the degree of vulnerability of that area to disasters. For example, a volcano erupting in an uninhabited area will not cause much loss. The capacity of the population to deal with or resist the disaster also plays a major role in determining the resulting damage. Natural disasters may further be classified into two types -— major natural disasters that include floods, cyclones, drought and earthquakes, and minor natural disasters such as cold waves, thunderstorms, heat waves, mud slides and storms.
Disasters that are based on deliberate human intent and negligence or events that involve the failure of a system, and which result in destruction at a considerable scale may be termed as man-made disasters. Major man-made disasters include setting of fires, epidemics, deforestation, pollution due to prawn cultivation, chemical pollution and wars. Minor man-made disasters include road or train accidents, riots, food poisoning, industrial disasters or crises and environmental pollution. Man-made disasters are of two kinds:
- Technological: These are the result of failure of technology, such as malfunction of machines, transport accidents or environmental disasters caused by human error.
- Sociological: These may be termed as disasters that have been deliberately caused by human beings because of a strong motive of destruction, such as riots, wars, terrorist acts, stampedes, etc.
Disaster management entails the prospect of avoiding disasters by developing adequate methods and emergency preparedness plans, which may be implemented in the time of a crisis in order to save life and property. Quite often a hazard results in a disaster when the local emergency management proves to be incompetent to deal with the situation at hand. The science of disaster management, thus, basically deals with knowing the vulnerability of that area (often in terms of natural disasters) and being equipped with knowledge and methods of practical application so as to minimise the cataclysmic effects of a disaster.