Geographicalnotes

Of all natural hazards, the most insidious is drought. However, for some countries such as Australia and United States, droughts have not led to starvation, but to spectacular fires as tinder-dry forests ignite, grasslands burn and eucalyptus bushland erupts in flame. Fire hazard is the most common hazard, which is present in all areas of life. Most combustible materials are stored in a normal atmosphere, which contains oxygen, and so the risk of fire is then due to the possibility of an ignition source. Fire  is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. Three elements are required to start and sustain fire: (1) oxygen, (2) fuel, and (3) heat. To start a fire, source of ignition such as a spark, flame and high temperature are needed. Diagram for understanding the necessary ingredients for most fires. The fire extinguishes by removing anyone of the elements in the fire triangle...

A cyclone is a vast, violent whirl in the atmosphere which moves from the high seas towards the coastal areas. A cyclone will often bring with it heavy rains that can cause flooding. In order for a cyclone to form, the ocean waters need to be warm, at least 26°C. Above the warm ocean, water evaporates and forms clouds. If there is low air pressure where the clouds are formed, it pulls them in and they begin to rotate. It is the earth rotating and spinning on its axis that causes  the cyclone’s clouds to rotate. Cyclones are caused by atmospheric disturbances around a low -pressure area distinguished by swift and often destructive air circulation. Cyclones are usually accompanied by violent storms and bad weather. The air circulates inward in an anticlockwise direction in the Northern hemisphere and clockwise in the Southern hemisphere. Cyclones are classified as: (i) extra tropical cyclones (also called temperate cyclones); and (ii) tropical cyclones. Fig: Major Disaster in ...

Responses to hazard:  Preparedness,  Trauma and aftermath,  Resilience and capacity development Responses to hazard A hazard is an agent which has the potential to cause harm to a vulnerable target. Hazards can be both natural or human induced. According to Alexander (2000, p. 7), “a  hazard is an extreme geophysical event that is capable of  causing a disaster.” The word “extreme” is used here to signify a substantial departure  (either in the positive or the negative direction) from a mean or a trend. Although Alexander did not specify the distinction between these two terms in his definition, it does suggest that hazards may transform into disasters and thus become sequential events. That is, every disaster starts with a hazard (Thywissen, 2006). Hazards are harmful to people, but it fails  to recognize people’s role in causing or  amplifying the impacts associated with hazards. For example, floods can originate either ...