Preventive Resettlement of Populations at Risk of Disaster - GFDRR

Ecuador and Peru) are estimated to live in earthquakeprone
areas. 17 Also, in the Caribbean basin, the tectonic
configuration makes the islands significantly prone to
volcanic and seismic hazards.
The topography, especially the Andes in South America
and the Meso-American highlands in Central America,
is associated with the climatic dynamics that trigger
frequent mass movements and floods. These mountain
chains create a divide between the Pacific slopes,
with watersheds and shorter rivers that can produce
flash flooding, and the Atlantic and Caribbean slopes,
with vast plains in which rivers encounter conditions
conducive to slow-growing floods. The climate also
leaves its imprint on other parts of the region, as in
the Caribbean, with its annual tropical storms and
hurricanes, and in areas off the coast of Peru, where the
El Niño-Southern Oscillation phenomenon (ENSO)
begins and then causes floods and drought in various
parts of LAC.
Often, these hazards occur in a chain reaction,
which increases the magnitude of their impact. In
mountainous areas, of which there are many in the
region, tectonic hazards and heavy rains can give
rise to mass movements, such as mudslides or floods.
Droughts may also create the conditions for forest
fires which “set the ground” to exacerbate flooding: for
example, the extensive drought triggered by El Niño
in 1997-1998 made the vegetable biomass in Central
America much more combustible (CCAD, 1998). The
severe shortage of water and the delayed start of the
rainy season in 1998 allowed fires to spread rapidly;
therefore the heavy rainfall unleashed by Hurricane
Mitch found large areas devoid of vegetation, which
increased soil saturation levels, and caused surface
runoff (Sanahuja, 1999).
In short, the diversity and intensity of the geological and
hydrometeorological dynamic in LAC create a “multiple
hazards” scenario, characterized by dangerous events,
such as earthquakes, volcanic eruptions, tsunamis,
landslides, storms, floods, forest fires and droughts.
2.4 Vulnerability and Risk-driving
Factors
As indicated at the beginning of this chapter, disasters cannot
be analyzed outside the social, economic, political and
environmental contexts in which they occur. Accordingly,
there is broad consensus that the increase in disastrous
events is rooted in a process of increasing vulnerability.
There have been numerous attempts to define the concept
of vulnerability to disasters and to classify it under
multiple headings, but all researchers view vulnerability
as a state of “being prone to” or being “susceptible to
damage and harm” (Blaikie et al., 1996). In the mid-1990s,
two models were proposed to explain the underlying
causes of increased vulnerability. Figure 1.11 shows one
of those models, called PAR (Pressure and Release),
which examines the evolution of unsafe conditions in the
form of dynamic pressures. Examples of these conditions
are urbanization and environmental degradation, whose
causes are found in the political economy.
The processes that shape the emergence of vulnerable
scenarios are varied, complex and differentiated by subregion,
country, and areas within them. Any attempt
to describe them in broad terms could over-simplifies
the issues. Nevertheless, it is possible to identify some
of the major factors driving vulnerability and risk, such
as rapid urbanization and environmental degradation,
exacerbated in a vicious circle by poverty and persistent
weak governance. It is also assumed that these factors
are inter-related, so that effective and comprehensive
intervention in all of them is essential to reduce disaster
risks. One way to present an integrated picture of those
driving vulnerability forces is to examine both urban
and rural areas.
2.5 Urban Areas and the
Construction of Vulnerabilities
One notable feature in LAC is that it constitutes the most
urbanized part of the developing world. In 1950, urban
residents accounted for 41.4 percent of the total population;
by 2007, the figure had soared to 78.3 percent and
17
Atlas de las dinámicas del territorio andino: población y bienes expuestos a amenazas naturales [Atlas of the dynamics of the Andes: population
and property exposed to natural hazards], General Secretariat of the Andean Community, Cali: Corporación OSSO, 2009).
10
Preventive Resettlement of Populations at Risk of Disaster: Experiences from Latin America