Progress and gaps in climate change adaptation in coastal cities across the globe

Coastal cities are at the frontlines of climate change impacts, resulting in an urgent need for substantial adaptation. To understand whether and to what extent cities are on track to prepare for climate risks, this paper systematically assesses the academic literature to evaluate climate change adaptation in 199 coastal cities worldwide. We show that adaptation in coastal cities is rather slow, of narrow scope, and not transformative. Adaptation measures are predominantly designed based on past and current, rather than future, patterns in hazards, exposure, and vulnerability. City governments, particularly in high-income countries, are more likely to implement institutional and infrastructural responses, while coastal cities in lower-middle income countries often rely on households to implement behavioral adaptation. There is comparatively little published knowledge on coastal urban adaptation in low and middle income economies and regarding particular adaptation types such as ecosystem-based adaptation. These insights make an important contribution for tracking adaptation progress globally and help to identify entry points for improving adaption of coastal cities in the future

A global assessment of actors and their roles in climate change adaptation

An assessment of the global progress in climate change adaptation is urgently needed. Despite a rising awareness that adaptation should involve diverse societal actors and a shared sense of responsibility, little is known about the types of actors, such as state and non-state, and their roles in different types of adaptation responses as well as in different regions. Based on a large n-structured analysis of case studies, we show that, although individuals or households are the most prominent actors implementing adaptation, they are the least involved in institutional responses, particularly in the global south. Governments are most often involved in planning and civil society in coordinating responses. Adaptation of individuals or households is documented especially in rural areas, and governments in urban areas. Overall, understanding of institutional, multi-actor and transformational adaptation is still limited. These findings contribute to debates around ‘social contracts’ for adaptation, that is, an agreement on the distribution of roles and responsibilities, and inform future adaptation governance