Assessment of the exposure to coastal flood risk by inhabitants of French coasts: The effect of spatial optimism and temporal pessimism

摘要

The increase in coastal population exposure to coastal flood risk can be explained by the concentration of stakes particularly induced by property development in areas exposed to coastal flooding. To this trend is added the sea level rise expected in 100 years, which leads to an increased coastal flood risk. This research analyzes how inhabitants perceive the exposure to coastal flood risk at different spatial and temporal levels. In this way, 318 individuals were surveyed in four coastal municipalities in France (Barneville-Carteret, Saintes-Maries-de-lamer, Chatelaillon-Plage and Sainte-Anne). Our research is based on two major assumptions that relate to the optimistic bias. First, we assumed that individuals are likely to perceive proximate areas more favorably than distant areas, in other words their assessment of exposure to coastal flood risk may increases as spatial level increases. Second, we assumed that individuals tend to believe that risk would be greater in the future than in the present, so their assessment of exposure may increases as temporal levels increases. We confirmed those assumptions and determined local and global level as significant levels of assessment. Respondents tend to assess their home exposure lower than the one of more distant spatial levels. However, it is precisely at the local level that prevention and risk reduction measures are the most carried out as they are relevant to community engagement.