Risk assessments are key for the effective management of potential environmental threats. Across probabilistic phenomena, climate change is an exemplar of paramount uncertainties. These uncertainties have been embraced in supporting governments’ decisions; yet receive scarce attention when studying individual behavior. Analyzing a survey conducted in the USA, China, Indonesia, and the Netherlands (N=6242), we explore socio-economic, psychological, and behavioral differences between individuals who can subjectively assess risks, and those who are risk-uncertain. We find that risk-uncertain individuals are more likely to belong to societal subgroups classically considered as vulnerable, and have reduced capacities and intentions to adapt to hazards—specifically floods. The distinctions between risk-aware and risk-uncertain individuals indicate that ignoring differences in individuals’ capacity to assess risks could amount to persistent vulnerability and undermine climate-resilience efforts. While we use floods emblematically, these finding have consequences for the standard practice of dropping or bootstrapping uncertain responses, irrespective of the hazard, with implications for environmental management.@en

As climate change increases the probability and severity of natural hazards, the need for coordinated adaptation at all levels of society intensifies. Governmental-level adaptation measures are essential, but insufficient in the face of growing risks, necessitating complementary action from households. Apprehending the drivers of household adaptation is critical if governments are to stimulate protective behavior effectively. While past work has focused on the behavioral drivers of household adaptation, little attention has been paid to understanding the relationships between adaptation measures themselves—both previously undergone and additionally (planned) intended adaptation(s). Using survey data (N = 4,688) from four countries—the United States, China, Indonesia, and the Netherlands—we utilize protection motivation theory to account for the behavioral drivers of household adaptation to the most devastating climate-driven hazard: flooding. We analyze how past and additionally intended adaptations involving structural modification to one's home affect household behavior. We find that both prior adaptations and additionally intended adaptation have a positive effect on intending a specific adaptation. Further, we note that once links between adaptations are accounted for, the effect that worry has on motivating specific actions, substantially lessens. This suggests that while threat appraisal is important in initially determining if households intend to adapt, it is households' adaptive capacity that determines how. Our analysis reveals that household structural modifications may be nonmarginal. This could indicate that past action and intention to pursue one action trigger intentions for other adaptations, a finding with implications for estimating the speed and scope of household adaptation diffusion.@en

Understanding social and behavioural drivers and constraints of household adaptation is essential to effectively address increasing climate-induced risks. Factors shaping household adaptation are commonly treated as universal, despite an emerging understanding that adaptations are shaped by social, institutional and cultural contexts. Using original surveys in the United States, China, Indonesia and the Netherlands (N = 3,789), we explore variations in factors shaping households’ adaptations to flooding, the costliest hazard worldwide. We find that social influence, worry, climate change beliefs, self-efficacy and perceived costs exhibit universal effects on household adaptations, despite countries’ differences. Disparities occur in the effects of response efficacy, flood experience, beliefs in governmental actions, demographics and media, which we attribute to specific cultural or institutional characteristics. Climate adaptation policies can leverage the revealed similarities when extrapolating best practices across countries yet should exercise caution, as context-specific socio-behavioural drivers may discourage or even reverse household adaptation motivation.@en

Natural hazards, exacerbated by climate change, increasingly affect societies worldwide. The accelerating risks entail that private adaptation complement more traditional public climate change adaptation measures. Culture plays an important role in framing how individuals experience hazards and behave toward them. Yet, empirical research explicitly measuring whether and how climate change adaptation varies across cultures is lacking. To address this gap, we collect meta-analytic data on factors motivating individual flooding adaptation from 25 countries and more than 50 publications. Employing Hofstede's Cultural Rankings as a metric of national culture, we model the effect of culture on adaptation motivation of individual households using meta-regression analysis. We find a number of statistically significant relationships between culture and factors motivating private climate change adaptation. Hence, cultural context is vital to consider when designing and implementing climate change adaptation policies, simulating the uptake of individual hazard prevention measures, or integrating private adaptation in assessing costs of climate change in integrated assessment models. These findings are among the first to provide empirical evidence on the interaction effects between culture and private climate change adaptation motivation.@en

Coastal areas around the world are urbanizing rapidly, despite the threat of sea level rise and intensifying floods. Such development places an increasing number of people and capital at risk, which calls for public flood management as well as household level adaptation measures that reduce social vulnerability to flooding and climate change. This study explores several private adaptation responses to flood risk, that are driven by various behavioral triggers. We conduct a survey among households in hazard-prone areas in eight coastal states in the USA, of which, some have recently experienced major flooding. While numerous empirical studies have investigated household-level flood damage mitigation, little attention has been given to examining the decision to retreat from flood zones. We examine what behavioral motives drive the choices for flood damage mitigation and relocation separately among property buyers and sellers. Hence, we focus on the drivers that shape demand for future development in flood-prone cities. We find that households’ choices to retreat from or to avoid flood zones (1) are highly sensitive to information that provokes people's feelings of fear, and (2) rely on hazardous events to trigger a protective action, which ideally would take place well before these events occur. We highlight that major flooding may cause a potential risk of large-scale outmigration and demographic changes in flood-prone areas, putting more low-income households at risk. Therefore, coordinated policies that integrate bottom-up drivers of individual climate adaptation are needed to increase urban resilience to floods.@en