whether projected urbanization is incorporated into urban and environmental policy (UNFPA, 2007). As discussed above, LECZs have a heightened vulnerability that is associated with sea level rise, and, in the developing world, they contain many large- and medium-sized cities. Population growth in urban LECZs is projected to be particularly high. Due to these population changes over the next decades, exposure to hazards from sea level rise will increase significantly (McGranahan et al., 2007; Balk et al., 2009)—an increase that would not be captured without incorporation of population dynamics. Given that some of the population growth in LECZs is driven by migration, this growth makes the “climate migration” discussion more complex in that many people are moving towards, not away from, exposure. In doing so, however, they may be increasing their adaptive capacity through better and more resilient livelihoods. Population density can help to determine how many people are at risk and how access to services is distributed across populations. Density is highly dependent on interactions with the built environment, socioeconomic status, social capital, and prevalence of services and institutions in its relationship with exposure (Dodman, 2009). People in high density areas can be extremely exposed, as is the case in urban slums in LECZs; for instance, significant increases in population density in cities in Bangladesh have resulted in greatly increased flood exposure (Alam and Rabbani, 2007; Dodman, 2009). At the same time, however, clustering people at higher densities in safer locations can reduce exposure to climatic threats or can make the provision of protective infrastructure more cost-effective. Urban slums can bring together each of the dimensions of exposure referred to above, frequently combining geographic risk, poor infrastructure and the built environment, poverty and population factors, including high density, that can exacerbate exposure. For example, the image of an urban slum in Bacon Poblacion, Sorsogon, Philippines (see Figure 1.2), illustrates how these factors can come together in a single location. Hasan et al. (2010) applied innovative design models to case studies of urban slums in
Photo: David Dodman
Figure 1.2: Bacon Poblacion, Sorsogon, Philippines
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The De mogra ph y of Ada ptation to C l imate Ch ange
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