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Natural Disasters: Capacity and Risk

This article defines the capacity and risk of a natural disaster, and also discusses the vulnerability of those who may be affected

What is capacity?

Capacity is the community’s ability to combat or prevent damage.

This is through local resources and expertise, which can be in the form of material possessions, social organisations or institutions capable of mobilising available assets (Wright and Vesala-Husemann 2006). Capacity can limit the destruction that is possible through the hazard and vulnerability present in a community. The three factors taken together show the risk or the probability of harmful consequences or expected losses that can result from the disaster.

What is Risk?

Risk can be said to refer to the expected losses (lives lost, persons injured, damage to property and disruption of economic activity or livelihood) caused by a particular phenomenon (hazard). In the case of an emergency situation, there is a formula to estimate the possible losses:

((H, times, V) – C = R)
((Hazard, times, Vulnerability) – Capacity = Risk)

When a disaster strikes a community, these situations not only result in a loss of life and property damage but are also a hindrance to development efforts within the country or region. They also disrupt social and economic systems, result in extensive harm to the environment and can destroy local resources and capacity (Davis and Lambert 2002, Wright and Vesala-Husemann 2006).

Despite the destructive nature of disasters, there can be a silver lining. For a period of time after these events, there is an influx of financial and technological aid, corrupt political systems can be overturned and new measures can be introduced to prevent the same level of destruction from occurring in the event of a future disaster (Davis and Lambert 2002).

In this calculation, hazard is the potential threat posed by the event. The characteristics that define this aspect of the formula depend on the community. In an affluent community, flooding could be just considered an annoyance while in an area with a higher prevalence of poverty, flooding can result in a complete loss of livelihood (Fara 2001). Tied into hazard is the vulnerability of an area.

While disaster situations present a plethora of hazards, there are additional hazards that could be present in the area or community before the event, which can exacerbate the situation. In emergency situations stemming from natural disasters, the environment plays a large role, especially as the number of these types of disasters occurring annually has risen because of human influence (Davis and Lambert 2002, OCHA 2008).

As global environmental conditions deteriorate, local micro-level ecological systems are disrupted as well. If a plot of land is being over-farmed and the soil sapped of its nutrients, the plants capable of being harvested will decrease. Add to this situation the development of a drought and the community now has the makings of a famine (Fara 2001).

Vulnerability of the affected people

The situation of vulnerable populations can be worsened by the hazards that disaster situations introduce, as well as by several other factors. Poverty, especially abject poverty, creates a segment of people that are extremely vulnerable. These people usually live in areas that are more likely to be subject to natural disasters, such as drought or flooding, and also suffer from illness, insufficient education, malnutrition and other maladies (OCHA 2008, Fagen 2008).

The vulnerabilities that exist before disasters strike are only exacerbated after the event. Groups that exist in subordinate positions because of their class status, racial or ethnic group or gender before a disaster, and, as such, have less access to any social safety nets that exist prior to a disaster, will be more severely affected by the damage caused by the event (Yodmani 2001).

It is in part because of this that vulnerabilities cannot merely be considered at face value. There are root problems to every factor that increase the susceptibility of groups to the effects of emergency situations. Poverty is one of the main characteristics that are considered to create a vulnerable population, but as Yodami (2001: 483) puts forth:

‘…while it is clear that the poor are often those most affected by a disaster, it is too simplistic to assume that there is a direct and absolute correlation between poverty and vulnerability. Poverty, as an indicator of lack of access to resources and income opportunity, is only one of the several dimensions of vulnerability.’

The more vulnerable a population is the less likely it is that they will have access to the institutions that increase their capacity in dealing with the effects of a disaster. However, even when there is a lack of formal structure that offers services such as granting access to clean water or food, there usually exists in some form a social network between neighbours (Yodami 2001). Despite this, disasters frequently overwhelm a countries capacity to mitigate the damage caused by the event. This is especially true in developing nations in which the country is susceptible to multiple disasters in a short period of time (Thomalla et al 2006).

Bringing together hazard, vulnerability and capacity

Hazard, vulnerability and capacity are all tied together. The more vulnerable a population is the more likely it is that they will be adversely affected by the hazards present before and after a disaster. Also, the more vulnerable a group is the less likely it is that they will have the capacity to decrease the impact of the disaster. However, even capacity at the level of the family helps to reduce the effects of the hazards present and how vulnerable a population is considered to be. These three characteristics must be taken together can tell a planner what the expected risk is in the case of an emergency, which can help with planning and can further reduce the chance of severe damage.


Davis, J. and Lambert, R., (2002). Engineering in emergencies. A practical guide for relief workers: Practical Action Publishing.

Fagen, P., (2008). Natural disasters in Latin America and the Caribbean: national, regional and international interactions. London. UK. [online] Available from Accessed on [10 May 2019]

Fara, K., (2001). ‘How natural are ‘natural disasters’? Vulnerability to drought of communal farmers in Southern Namibia’. Risk Management, 3(3), pp.47-63. [online] available from Accessed on [10 May 2019]

Thomalla, F., Downing, T., Spanger-Siegfried, E., Han, G. and Rockström, J. (2006). ‘Reducing hazard vulnerability: towards a common approach between disaster risk reduction and climate adaptation’. Disasters, 30(1), pp.39-48. [online] Available from Accessed on [10 May 2019]

Wright, M., Vesala-Husemann, M., (2006). ‘Nutrition and Disaster Preparedness: Focusing on Vulnerability, Building Capacities’. OJIN: The Online Journal of Issues in Nursing. [online] Vol. 11 No. 3, Manuscript 5. Available from: Accessed on: [10 May 2019]

Yodmani, S., (2001). Disaster risk management and vulnerability reduction: Protecting the poor. The Center.

© Coventry University. CC BY-NC 4.0
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