6.7 Conclusions: implications for sustainable development

The main conclusions are reported in the Executive Summary and are reviewed here in the context of sustainable development. Coastal ecosystems are dynamic, spatially constrained, and attractive for development. This leads to increasing multiple stresses under current conditions (Section 6.2.2), often resulting in significant degradation and losses, especially to economies highly dependent on coastal resources, such as small islands. Trends in human development along coasts amplify their vulnerability, even if climate does not change. For example, in China 100 million people moved from inland to the coast in the last twenty years (Dang, 2003), providing significant benefits to the national economy, but presenting major challenges for coastal management. This qualitative trend is mirrored in most populated coastal areas and raises the conflict between conservation and development (Green and Penning-Rowsell, 1999). Equally the pattern of development can have tremendous inertia (Klein et al., 2002) and decisions made today may have implications centuries into the future (Box 6.6).

Climate change and sea-level rise increase the challenge of achieving sustainable development in coastal areas, with the most serious impediments in developing countries, in part due to their lower adaptive capacity. It will make achieving the Millennium Development Goals (UN Secretary General, 2006b) more difficult, especially the Goal of Ensuring Environmental Sustainability (reversing loss of environmental resources, and improving lives of slum dwellers, many of whom are coastal). Adapting effectively to climate change and sea-level rise will involve substantial investment, with resources diverted from other productive uses. Even with the large investment possible in developed countries, residual risk remains, as shown by Hurricane Katrina in New Orleans (Box 6.4), requiring a portfolio of responses that addresses human safety across all events (protection, warnings, evacuation, etc.) and also can address multiple goals (e.g., protection of the environment as well as adaptation to climate change) (Evans et al., 2004a; Jonkman et al., 2005). Long-term sea-level rise projections mean that risks will grow for many generations unless there is a substantial and ongoing investment in adaptation (Box 6.6). Hence, sustainability for coastal areas appears to depend upon a combination of adaptation and mitigation (Sections 6.3.2 and 6.6.5).

There will be substantial benefits if plans are developed and implemented in order to address coastal changes due to climate and other factors, such as those processes that also contribute to relative sea-level rise (Rodolfo and Siringan, 2006). This requires increased effort to move from reactive to more proactive responses in coastal management. Strengthening integrated multidisciplinary and participatory approaches will also help improve the prospects for sustaining coastal resources and communities. There is also much to be learnt from experience and retrospective analyses of coastal disasters (McRobie et al., 2005). Technological developments are likely to assist this process, most especially in softer technologies associated with monitoring (Bradbury et al., 2005), predictive modelling and broad-scale assessment (Burgess et al., 2003; Cowell et al., 2003a; Boruff et al., 2005) and assessment of coastal management actions, both present and past (Klein et al., 2001). Traditional practices can be an important component of the coastal management toolkit.