Vulnerability can be referred to as “the degree of susceptibility to a natural hazard” (Lewis 1999: 4, as cited in WeAdapt, 2011). Hazards can be described as “potentially damaging physical events, phenomena, or human activities that cause loss of life, injury, property damage, social and economic disruption, or environmental degradation” (Makoka & Kaplan, 2005). Risk, when related to disaster, relates to the consequences of naturally occurring hazards on agricultural land, infrastructure and communities (Geoscience Australia, n.d.).
A natural hazard can threaten people in a destructive way. This fall-out effect is referred to as a natural disaster. That is to say, at the time the threat of a hazard actually takes place and hurts people, it is classed as a natural disaster. The consequent disasters and natural hazards are due to processes which have taken place throughout the history of the world, and occur naturally. All forms of hazardous processes can have tertiary, secondary and primary effects (Nelson, 2016).
Risk is symptomatic of the connection between geologic processes and humans (Nelson, 2016). In the case of risk, maps, for example, are often drawn up to highlight areas with a vulnerability to high hazard. This hazard includes cyclones, floods and earthquakes. In order to truly comprehend the possible effect of natural disasters on countries, provinces and communities, however, a more comprehensive apprehension of the risks that communities are faced with, is essential. That is to say, instead of just distinguishing which regions have the highest risk of a flood or earthquake, the risk assessment can for instance, offer essential data on which communities are the most susceptible to earthquakes, or on the number of individuals who would be left without a home in a 6.5 magnitude earthquake or a in a one in a hundred year flood (Geoscience Australia, n.d.).
Vulnerability involves the way in which a hazard impacts people and property (Nelson, 2016). Assessments and analysis of vulnerability look at a specific unit of concern or group, such as communities living on the coast, and then aim to ascertain the risk relating to particular harmful consequences for that community: “in face of a variety of stresses, and to identify a range of factors that may reduce response capacity and adaptation to stressors” (WeAdapt, 2011). Conceptually, vulnerability in a social sense has been seen in regard to an individual’s ability to “anticipate, cope with, resist and recover from… a natural hazard” (Wisner, Blakie, Canon & Davis, 2004, p. 11, as cited in FERMA, n.d).
When a disaster arises, the three components: hazard, risk, and vulnerability interplay and come together. A hazards impacts the population at risk whereas vulnerabilities are the internal components which impact the change of a hazards into a disasters. That is to say, the vulnerabilities influence the impact of a hazard on a specific population (Birkman, 2007). To that end, in order for a society to decrease and prepare for a disaster, the vulnerabilities in a specific population need to be measured, and the risk exposure needs to be determined.
In summary, hazard, risk, and vulnerability are extrinsically linked, and work in unison. If all these elements are not taken into account, then communities will not be sufficiently prepared for when a disaster does occur.