Informing climate investment priorities for Coastal Populations

International audienceSince the 1990s, the Intergovernmental Panel on Climate Change (IPCC) has used global level analyses of vulnerability to inform investment and action against the effects of climate change. Beyond the IPCC, the practice has been used widely to understand the vulnerability of coastal areas to a variety of hazards, including climate change. These analyses, however, have been driven by objectives that change from one assessment to the next, with very different conceptualisations of vulnerability. Over time these analyses have become increasingly data intensive and complex, drawing from an ever-expanding number of indicators. Such variations in objectives, conceptualisations and data have led to different and often contradictory rankings of priority areas for climate change action. The increased complexity makes it more difficult to disentangle the root causes of these different rankings and the degree to which climate change influences vulnerability rankings, compared to other factors such as local environment factors and the adaptive capacity of populations to deal with environmental change. If these global indicator analyses were deconstructed, climate decision-makers could use them as scoping studies rather than expect them to provide comprehensive and robust priorities for investment. Such scoping studies, if they are to be truly useful to climate decision-makers, need to be simplified and harmonised to isolate climate change specific drivers. They can help target the locations for more in-depth local level analyses and should be supplemented by global level analyses of costs of climate action including technical, social and economic factors