Preventive Resettlement of Populations at Risk of Disaster - GFDRR

Chapter 1
Global and Latin America and the
Caribbean Natural Disaster Trends
By Haris Sanahuja
Disasters are the result of the overlapping in time
and space, of a natural phenomenon of certain
intensity —that is, a hazard—with a population
exposed to its impact. A natural phenomenon cannot be
considered a hazard unless it is analyzed in a socioeconomic
context where its occurrence can affect society.
This context also influences the level of susceptibility to
damage—that is, vulnerability—to a particular hazard.
When a hazard affects two areas with different socioeconomic
and environmental contexts, the level of damage
depends on these differences.
The Caribbean region, with its diverse island states and
annual tropical storms, offers a useful area in which to
analyze the effects of the same natural disaster. Indeed,
the differences in the extent of damage from tropical
storms are related to different levels of vulnerability. For
example, the low level of human development and severe
environmental degradation in Haiti greatly explain
why the damage is likely to be far larger than in other
Caribbean states, despite similar levels of exposure.
Likewise, the impacts are generally lower in countries
with more highly developed disaster preparedness, such
as Cuba and Jamaica. 1
Thus, the probability of a disaster and the magnitude of
its impact are defined as the product of two factors – the
level of the hazard and the degree of vulnerability – which
together constitute risk. Accordingly, disasters show
where, how and for whom the risk translates into human
and material damages and losses. Analyses of the spatial
and temporal distribution of the occurrence and impacts
of disasters provide critical information for assessing the
level of risk. The geographical distribution and magnitude
of the effects allow analysts to (a) gauge the scope
of the problem, (b) urge that it be a public policy issue,
(c) identify trends and (d) prioritize actions in the field of
disaster risk reduction.
1. Global Patterns and Trends
in the Occurrence and Impacts
of Disasters
Information about the occurrence and effects of disasters
worldwide since the beginning of the 20th century
is available in the global Emergency Events Database
(EM-DAT). 2 EM-DAT statistics show that the number
of disasters—triggered by the occurrence of natural
hazards—has accelerated sharply worldwide (see figure
1.1). 3
Although some argue that the increased number of
disasters shown in Fig. 1.1., up to the 1970s, is due to
improved registering and the existence of scientific
centers that monitor these events, the upward trend
has been confirmed for the past four decades through
1
For the links between the impact of disasters and human development, see UNDP (2004).
2
EM-DAT was established in 1988 by the Centre for Research on the Epidemiology of Disasters (CRED) with the support of the Office of
Foreign Disaster Assistance (OFDA) of the United States Agency for International Development (USAID). It contains data on the occurrence
and effects of natural and technological disasters in the world, reported since 1900. See http://www.cred.be.
3
Figure 1.1 includes only disasters associated with hydrometeorological and geological hazards. Biological hazards (such as epidemics and
insect infestation) were excluded from the analysis because they fall outside the scope of this analysis.
4
EM-DAT distinguishes between disasters associated with natural hazards (natural disasters) and technological disasters. Natural disasters
include three types: geological hazards (earthquakes, volcanic eruptions, landslides due to tectonic movements, and tsunamis); hydrometeorological
hazards (floods, droughts, storms, extreme temperatures, forest fires, and landslides due to hydrological causes); and biological
hazards (epidemics and insect infestation).
Chapter 1 Global and Latin America and the Caribbean Natural Disaster Trends
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