Change is the continuous process of nature. Those changes which are in the interest of man kind are considered as boon of nature but when changes are not beneficial to man they are called curse of nature or natural disaster. Natural disaster is a change or event which occurs in few seconds. Problems resulted after happening are called dangers cause by Natural disaster.
For disaster one reason is not responsible but combined reasons are responsible. External and internal forces of earth directly affect the disaster, for example, Earthquake, Volcano etc. unwise and continuous exploitation of resources by man, use of earth in different ways by growing population have deformed the earth. Deforestation, weathering of rocks, water crises are the result of such activities. Such problems have given birth to global warming.
All these above mentioned causes are combinedly responsible for natural calamities.
Natural balance is disturbed by man due to man’s greedyness and consumer satisfaction view. For his blind development he has disturbed the balance of nature. Man’s activity are indirectly inviting these natural disaster.
Classification of Natural disaster on the basis of origin:
1. Change in earth: Calamities which occur due to sudden change inside the earth.
For example: Earthquake, rock sliding, glaciers sliding and volcano. In India volcanoes are not active.
2. Seasonal calamities: They are caused by seasonal change.
For example: Cyclones, Tsunami, flood, etc.
3. Calamities caused by living beings: They are caused by bacteria and living things.
For example: epidemics, dead animals, plague, malaria, etc.