A disaster occurs as the result of ahazardous event that dramatically affects a community.
There are six broad types of hazards:1. Atmospheric Ð for example, cyclones, hailstorms,blizzards or bushfires2. Hydrological Ð for example, flooding, waveaction or glaciers3. Geological Ð for example, earthquakes orvolcanoes4. Biological Ð for example, disease epidemicsand plagues5.Technological Ð for example, accidents, explosionsor hazardous materials6.Human Ð for example, war, crowd stampedeand terrorism.
The first four groupings are generally referredto as natural hazards and the last two as humanhazards. It should be noted that some naturalhazards are influenced by the actions andlocations of people. For example, the severity ofbushfires depends not only on the amount of fuelavailable or the strength and humidity of thewind. Humans influence bushfires through carelessnessin the use of ®re, inadequate preparationof their property in the event of a bushfire andpoor disaster planning.
Risk analysis is concerned with the chance of ahazardous event occurring and whether or not itcould result in a disaster. The map oppositeshows those areas of Australia that are vulnerableto the threat of natural disaster. It showsthat different types of hazards and disasters areprevalent in different parts of Australia. Forexample, cyclones located to the north of Australiaare associated with the warm tropicalocean; bushfires to the south of Australia areassociated with dry vegetation. People who moveto an area are usually aware if it is located in anatural hazard zone. For example, though Cairnsis subject to cyclones, the people of that communityhave decided that the benefits of living andworking there outweigh the risk factor.
ASSESSING THE RISKFew Australian communities are free of the risk ofnatural disasters, but some are more