6.6.2 Costs and benefits of adaptation

The body of information on costs of adaptation has increased dramatically since the TAR, covering the range from specific interventions to global aggregations. Most analyses quantify the costs of responses to the more certain and specific effects of sea-level rise. Selected indicative and comparative costs of coastal adaptation measures are presented in Table 6.11. They reveal a wide range in adaptation costs. But in most populated areas such interventions have costs lower than damage costs, even when just considering property losses (Tol, 2002, 2007). Climate change affects the structural stability and performance of coastal defence structures and hence significantly raises the costs of building new structures (Burgess and Townend, 2004) or upgrading existing structures (Townend and Burgess, 2004). Financial cost is not the only criterion on which adaptation should be judged – local conditions and circumstances might result in a more expensive option being favoured, especially where multiple benefits result.