Warning Fatigue or Cry-Wolf effect is a taken-for-granted phenomenon that can result from being ‘over-warned’. The terms are used to describe situations where individuals who are exposed to recurring warning messages about a disaster which then does not eventuate become cynical, apathetic and ‘tired’ of hearing warnings. They may become desensitised to the risk thereby endangering themselves even more. The assumption by practitioners (emergency managers and governmental policy-makers for example) that warning fatigue is a problem presents emergency agencies with a conundrum: they want to avoid the accusation of panicking the public but worry they may run the risk of under-preparing them at the same time. As a result, they may be tempted to err on the side of caution, delay issuing a warning and downplay the possible severity of a potential disaster. Examination of the literature, and an analysis of presentations and news stories have shown that policy-makers, emergency managers, academics and the public use the term ‘cry wolf’ or ‘warning fatigue’ in everyday life. They regard it as conventional wisdom and believe it can influence risk perception and warning response. Nonetheless it has been presumptively assigned by some disaster theorists to the category of a myth. A limited warning fatigue literature has examined the phenomenon in the context of rapid-onset disasters and has concluded that risk perception is not affected by warning fatigue. However, it also suggests there is a direct relationship between warning time, preparedness and response. This allows for the possibility that warning fatigue may not be a myth, but a function of the type of disaster, the frequency of warnings and warning lead-time. This thesis makes a distinction between rapid-onset and prolonged lead-time disasters and hypothesises that prolonged lead-time disasters are responded to in very differently ways than rapid-onset ones. Australian bushfires provide the context in which this research was conducted because bushfires are repeatedly warned about yet rarely (once every ten or twenty years) result in a major disaster. Using social constructionist and social representation theoretical frameworks, and integrating psychosocial and sociological perspectives, this thesis examines the role that warning fatigue plays in the risk perceptions, warning responses and decision-making processes of people living in bushfire-prone areas of Australia. Utilisation of a mixed methods design, a substantive literature review and two rounds of semi-structured interviews resulted in a conceptualisation of a bushfire warning fatigue measure (BWFM). Application of the measure among at-risk Australian communities validated the measure. Through empirical statistical analysis, this standardised instrument was revised (BWFM-R) and used to measure the change in warning fatigue levels over a fire season (November 2011-April 2012). Analysis showed that warning fatigue appears to be multi-faceted comprising five aspects: Trust and credibility, over-warning, false alarms, scepticism and helplessness. It was also found that warning fatigue responses are contextual and interconnected with ‘unofficial’ warnings (such as media stories). The direction of the change and analysis of the qualitative component of the survey implied that unofficial bushfire rhetoric from the media during the winter months may produce a warning fatigue effect, so that when the official warnings were issued at the beginning of the bushfire season, the public were already ‘tired’ of the message. Trust and credibility, over-warning, false alarms, scepticism and helplessness are not new factors in public warning response to disaster communication, but this research demonstrates that they can combine in a unique way to produce ‘warning fatigue’. It proposes that if emergency and disaster agencies differentiate between rapid-onset and prolonged lead-time disasters, understand the complexities of warning fatigue and design their warnings accordingly, then disaster risk communication will become more effective, increasing public engagement and improving disaster response.

This study used variables from the Protective Action Decision Model to guide data collection about 262 residents' responses to the 2009 Samoa M8.1 earthquake and tsunami. The results show that earthquake shaking, combined with knowledge that this can cause a tsunami, was the most common source of first awareness about a possible tsunami and that broadcast media were the most common first social sources of warnings. Radio was an important source of additional information, as were face-to-face contacts and phone calls. Contrary to previous research, few of the recommended elements of a warning message were communicated to those at risk and none of these message elements was significantly correlated with evacuation. Nonetheless, two thirds of coastal residents and half of inland residents began evacuations within 15. min after the earthquake. Those who had participated in earthquake hazard awareness meetings had higher risk perceptions but were no more likely to evacuate to higher ground or evacuate promptly. This study's results are broadly consistent with previous findings on disaster response but raise a number of unresolved questions about behavioral response to rapid onset disasters.

Social capital — resources that are available as a result of social relationships and connections — has been shown to be an important component across the various stages of a natural disaster, such as a hurricane. Additionally, research has shown that the importance of the different types of social capital — bonding, bridging, and linking — can vary as the disaster progresses from preparation, to the immediate aftermath, to long-term recovery. Yet, findings are not consistent regarding the impact of social capital on taking protective action (e.g., evacuation, shelter in home or community) following a hurricane warning. In this paper, we leverage an original survey of 1450 residents living in coastal communities in the Southeast and Gulf Coast regions of the United States to examine the role of social capital in stated behaviors in response to a hurricane warning. Additionally, we examine the stated likelihood of evacuating if advised to by close contacts (friends, family, and co-workers) and elite sources (emergency management officials, elected officials, and the media). We find that bonding social capital is associated with an increased likelihood to evacuate and shelter in home as well as an increased likelihood to listen to close contacts that encourage evacuation. In addition, we find that linking social capital is associated with an increased likelihood of evacuation if encouraged to by elite sources.

An association was tested between the presence of a television weather broadcaster on-screen and viewers’ likelihood to seek shelter, measured via risk perception and preventative behavior. Social networking websites were used to recruit respondents. Four clips of archived severe weather videos, one pair (on-screen and off-screen broadcaster) using the reflectivity product and another pair (on-screen and off-screen broadcaster) using velocity product, were presented to participants. Viewers’ trust and weather salience were also quantified for additional interactions. A relationship between viewers’ risk perception (preflectivity = 0.821, pvelocity = 0.625) and preventative behavior (preflectivity = 0.217, pvelocity = 0.236) and the presence of the broadcaster on-screen was not found. The reflectivity product was associated with higher risk perception and preventative behavior scores than the velocity product (prp = 0.000, ppb = 0.000).