Trust-Building Communication and Climate Risk Decision Making

A lack of public trust in governance institutions such as governments, federal agencies, and public health organizations limits national capacities to mitigate climate-related risks. Trustworthy sources of risk information are theorized to be more persuasive and more likely to motivate adaptive behaviors. Accordingly, this dissertation addresses relational and translational challenges of risk communication to support public health and safety by making climate science more accessible to communities at risk from extreme heat. This project developed and applied a theory-driven model of trust determination to understand how United States residents evaluate the trustworthiness of state governments and emergency management agencies. Using confirmatory factor analysis, a two-factor model of trustworthiness as self-reliability and source reliability was strongly empirically supported. This measurement model of trustworthiness was translated into experimental trustworthiness manipulations capable of creating statistically significant differences in perceptions of source reliability. The dissertation then tested the persuasive efficacy of trust-building risk messaging using randomized controlled trials, finding that when controlling for political ideology, message trust condition had a significant effect on attitudes toward extreme heat risk and preparedness as well as intentions to prepare for extreme heat events. Practical and theoretical implications are discussed.