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close this bookAn Overview of Disaster Management (Department of Humanitarian Affairs/United Nations Disaster Relief Office - United Nations Development Programme , 1992, 136 p.)
close this folderChapter 1. Introduction to disasters
close this folderCausal factors of disasters
View the document(introduction...)
View the documentPoverty
View the documentPopulation growth
View the documentRapid urbanization
View the documentTransitions in cultural practices
View the documentEnvironmental degradation
View the documentLack of awareness and information
View the documentWar and civil strife


The magnitude of each disaster, measured in deaths, damage, or costs for a given developing country increases with the increased marginalization of the population. This is caused by a high birthrate, problems of land tenure and economic opportunity, and the lack or misallocation of resources to meet the basic human needs of an expanding population. As the population increases, the best land in both rural and urban areas is taken up and those seeking land for farming or housing are forced to accept inadequate land. These offer less productivity and a smaller measure of physical or economic safety. The following section considers each of these issues.



Photo credit: UNHCR/M. Vanappelghem

The most important single influence on the impact of a disaster is poverty. All other factors could be lessened if the affected population were not also limited by poverty. Virtually all disaster studies show that the wealthiest of the population either survive the disaster unaffected or are able to recover quickly. Across the broad spectrum of disasters, poverty generally makes people vulnerable to the impact of hazards. Poverty explains why people in urban areas are forced to live on hills that are prone to landslides, or why people settle near volcanos or rivers that invariably flood their banks. Poverty explains why droughts claim poor peasant farmers as victims and rarely the wealthy, and why famines more often than not are the result of a lack of purchasing power to buy food rather than an absence of food. Increasingly, poverty also explains why many people are forced to move from their homes to other parts of their countries or even across borders to survive. Such crisis-induced migration poses considerable challenges both in terms of immediate assistance to the displaced and of longer-term development.

Population growth

There is an obvious connection between the increase in losses from a disaster and the increase in population. If there are more people and structures where a disaster strikes, then it is likely there will be more of an impact. The growth of population has been so spectacular that it is inevitable that more people will be affected by disasters because more will be forced to live and work in unsafe areas. Increasing numbers of people will be competing for a limited amount of resources (such as, employment opportunities, and land) which can lead to conflict. This conflict may result in crisis-induced migration. Such growth occurs predominantly in developing countries, resulting in various contributors to disasters.

Figure. 1.2 Population growth, 1750-2100.

Source: Thomas Merrick, et. al., “World Population in Transition,” Population Bulletin, Vol. 42, No. 2 (1986).

Rapid urbanization

Rapid population growth and migration are related to the major phenomenon of rapid urbanization. This process is also accelerated in developing countries. It is characterized by the rural poor or civilians in an area of conflict moving to metropolitan areas in search of economic opportunities and security. These massive numbers of urban poor increasingly find fewer options for availability of safe and desirable places to build their houses. Here again, competition for scarce resources, an inevitable consequence of rapid urbanization, can lead to human-made disasters.

Figure 1.3 Population projections for some disaster-prone cities.

Many landslides or flooding disasters are closely linked to rapid and unchecked urbanization which forces low-income families to settle on the slopes of steep hillsides or ravines, or along the banks of flood-prone rivers. Many earthquake victims in urban areas have been impoverished families whose sites have failed rather than their houses, usually through landslides onto the house or out from under it.

Figure 1.4 As population continues to grow, settlements spread to marginal and even unsafe areas.

Transitions in cultural practices

Many of the inevitable changes that occur in all societies lead to an increase in the societies’ vulnerability to disasters. Obviously, all societies are constantly changing and in a continual state of transition. These transitions are often extremely disruptive and uneven, leaving gaps in social coping mechanisms and technology. These transitions include nomadic populations that become sedentary, rural people who move to urban areas, and both rural and urban people who move from one economic level to another. More broadly, these examples are typical of a shift from non-industrialized to industrializing societies.

One example of the impact of these transitions is the introduction of new construction materials and building designs in a society that is accustomed to traditional materials and designs. This often results in new materials being used incorrectly. In disaster prone areas, inadequate new construction techniques may lead to houses that cannot withstand earthquakes or wind storms (see the following figure).

Figure 1.5 New house badly built using modern materials.

Compounding this problem is the new community where the disaster survivors find themselves may not have a social support system or network to assist in the relief and recovery from the disaster. The traditional coping mechanisms may not exist in the new setting and the population becomes increasingly dependent on outside interveners to help in this process.

Conflicting as well as transitional cultural practices can also lead to civil conflict, for example, as a result of communal violence triggered by religious differences.

Environmental degradation

Many disasters are either caused or exacerbated by environmental degradation. Deforestation leads to rapid rain run off, which contributes to flooding. The destruction of mangrove swamps decreases a coast line’s ability to resist tropical winds and storm surges.

The creation of drought conditions - and the relative severity and length of time the drought lasts - is mainly a natural phenomena. Drought conditions may be exacerbated by: poor cropping patterns, overgrazing, the stripping of topsoil, poor conservation techniques, depletion of both the surface and subsurface water supply, and, to an extent, unchecked urbanization.

Figure 1.6 Deforestation for “development”

Lack of awareness and information

Disasters can also happen because people vulnerable to them simply didn’t know how to get out of harm’s way or to take protective measures. This ignorance may not necessarily be a function of poverty, but a lack of awareness of what measures can be taken to build safe structures on safe locations. Perhaps some people did not know about safe evacuation routes and procedures. Other populations may not know where to turn for assistance in times of acute distress. Nevertheless, this point should not be taken as a justification for ignoring the coping mechanisms of the majority of people affected by disasters. In most disaster-prone societies, there is a wealth of understanding about disaster threats and responses. This understanding should be incorporated into any efforts to provide external assistance.

War and civil strife

In this text war and civil strife are regarded as hazards, that is, extreme events that produce disasters. War and civil strife often result in displaced people, a target population of this training programme. The causal factors of war and civil strife include competition for scarce resources, religious or ethnic intolerance, and ideological differences. Many of these are also byproducts of the preceding six causal factors of disasters.

Q. Of the seven causal factors of disasters discussed above, how would you rank them for the region in which you live?

A. List the most serious contributor first.