A natural disaster could occur due to an immediate extreme event or it could be the result of a long duration process, which disrupts normal human life in its established social, traditional andeconomic system to a considerable extent. The UnitedNations define it as ".......... the occurrence of a sudden or major misfortune which disrupts the basic fabric and normal functioning of a society (or community)." Today, the term 'Disaster' is commonly used to denote any extreme event, be it natural or man-made, which brings about loss of life, property, infrastructure, essential services and means of livelihood to an extent that it becomes difficult to cope with the situation due to it being beyond the normal capacity of the affected communities to deal with unaided. A hazardous situation turns into a disaster event when the affected community (or district or state or country) needs immediate and prolonged assistance and support to deal with the situation and its aftereffects.
Thus, a disaster is the culmination of a hazard in a situation where the impact is accentuated by the vulnerability of the community. To be more specific, a hazard may be regarded as ape-disaster situation, in which some risk of disaster exists. In fact, hazards can be posed both by natural phenomena and by man-made events. By the same definition, disasters can be natural or man made. The man-made disasters will be covered in Course 2 and here we will confine ourselves to the study of natural disasters.
TYPES OF NATURAL DISASTERS
As already mentioned in section 1.1 above, India's unique geoclimatic position makes the country
particularly vulnerable to natural disasters. hdiais a vast peninsula of sub-continental size and is
surrounded by sea on three sides and has the Himalayan range on the fourth side, which has some
of the tallest mountains of the world. That is why India has to face avery large variety of disastrous
events of geological, oceanic or climatic origin. Thus we can list the natural disasters expected in
India on the basis of their origin as follows:
I Wind andlor Water related natural disasters
Floods
Droughts
Cyclones
Tsunmi
Climate related disasters
Heat and cold waves
Global wa~ming
Sea level rise
Ozone depletion