Exploring disaster impacts on adaptation actions in 549 cities worldwide

Whether disasters influence adaptation actions in cities is contested. Yet, the extant knowledge base primarily consists of single or small-N case studies, so there is no global overview of the evidence on disaster impacts and adaptation. Here, we use regression analysis to explore the effects of disaster frequency and severity on four adaptation action types in 549 cities. In countries with greater adaptive capacity, economic losses increase city-level actions targeting recently experienced disaster event types, as well as actions to strengthen general disaster preparedness. An increase in disaster frequency reduces actions targeting hazard types other than those that recently occurred, while human losses have few effects. Comparisons between cities across levels of adaptive capacity indicate a wealth effect. More affluent countries incur greater economic damages from disasters, but also have higher governance capacity, creating both incentives and opportunities for adaptation measures. While disaster frequency and severity had a limited impact on adaptation actions overall, results are sensitive to which disaster impacts, adaptation action types, and adaptive capacities are considered. Here the authors explore the effects of disasters on adaptation actions in 549 cities, finding that the effects of disaster frequency and severity are modest and depend on action type, population size, and adaptive capacity.

Automated summary

The influence of disasters on adaptation actions in cities is a subject of debate. The existing knowledge base mainly consists of individual or small-scale case studies, lacking a global overview of evidence on disaster impacts and adaptation. This study uses regression analysis to examine the effects of disaster frequency and severity on four types of adaptation actions in 549 cities. The results suggest that in countries with greater adaptive capacity, economic losses increase the level of adaptation actions targeting recently experienced disaster types, as well as actions to enhance general disaster preparedness. The frequency of disasters reduces actions targeting hazard types other than those that recently occurred, while human losses have minimal effects. Comparisons between cities with different levels of adaptive capacity reveal a wealth effect, as more affluent countries incur higher economic damages from disasters but also have greater governance capacity, leading to both incentives and opportunities for adaptation measures. Although the overall impact of disaster frequency and severity on adaptation actions is limited, the results are sensitive to the types of disaster impacts, adaptation actions, and adaptive capacities considered.