natural Hazards and Climate Change risks - GFDRR

Figure 8: The Classification of Urban, Peri-Urban, and Rural areas in the Dakar
Metropolitan Area
Some remarks on the limitations of the study
71. It can be seen that this study compiles and spatially analyses many components of
hazard (or disaster) risks, especially with regard to the spatial distribution and interaction of
major risk factors. On the other hand, the study is limited in the following respect: With the
available input information only the spatial distribution of relative hazard potentials can be
estimated. The absolute damage-frequency relationship and probabilities and their spatial
differentiation cannot be derived. So for instance absolute inundation levels and probabilities
cannot be determined, and it is not possible with a remote study to infer concrete figures
about coastal erosion. Likewise, the projected flooded areas in connection with the assumed
seal level rise scenarios are the result of simplifying assumptions (the only possible in such a
study), and do by no means mean that the flooded area will actually be of that extension.
72. With regard to vulnerability and exposure, mainly exposure-related information can
be derived. Vulnerability, as argued below, cannot be measured directly, but only inferred
with the help of indicators. In the context of this study we derive spatial indicators of
vulnerability from hot spots of exposure, assuming that extreme concentrations of exposure
will lead to locally increased vulnerability.
73. Finally, for this study no information on protection and prevention measures that may
be taken or planned by local authorities are known and included.
4.2 Map Generation
74. The map generation described in this chapter comprises
Land use and land use change for two periods (1988-1999, 1999-2008)
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