2011 AGU Fall Meeting

December 5-9, 2011
2011 American Geophysical Union (AGU) Fall Meeting

San Francisco, California
Katherine Thompson, graduate student, and CRED director David Krantz represented CRED at the 2011 American Geophysical Union Fall Meeting. Katherine presented a poster, “Why Don’t People Evacuate When Nature Threatens?” in the session on geophysical hazards and social/ecological vulnerabilities. Her poster summarized work– with other CRED scientists (co-directors Kenneth and Benjamin Orlove, and co-investigator, Robert Meyer) in collaboration with USGS Multi-Hazards Demonstration Project for Southern California.

Katherine Thompson, Kenneth Broad, Robert Meyer and Benjamin S. Orlove
Why Don’t People Evacuate When Nature Threatens?
Why do so many Southern Californians fail to evacuate when warned that winter storms have critically raised the risk of a debris flow in their neighborhoods? Have they perhaps not seen or heeded news coverage of past debris flow events? Are they unaware that recent fires made the hillsides above them more prone to gravity-driven processes? Do they think they can wait to start their cars until they can actually see the flow coming? Or have they merely experienced too many “false alarms” in past years, and no longer put much stock in the judgment of public officials or the ability of scientists to judge debris flow risk? In preparation for a simulation study that will place decision makers in a virtual house in the California foothills during a winter storm event, we explore the reasons that people do and do not evacuate in the face of potential debris flows. Working in collaboration with the USGS Multi-Hazards Demonstration Project for Southern California, we are surveying hundreds of local residents, from debris-flow prone areas and from elsewhere in the state, to establish their baseline knowledge (and misconceptions) about, attitudes toward, information use regarding, and experience with debris flows. Initial interviews with residents of recently hit neighborhoods give qualitative data suggesting that false-alarm effects and underestimation of risk are driving factors; these surveys will provide quantitative evidence to extend those findings. We will discuss the results of this survey in the context of a comprehensive body of psychology research that seeks to explain why people frequently appear to ignore or discount hazard warnings: neglecting to insure their homes and crops (Kunreuther, 1984), failing to evacuate in the face of storms and fires (Baker, 1991; Packham, 1995), and (barring a recent, vivid event) showing little support for measures that would manage or mitigate future hazards (Kunreuther, 2006a, 2006b; Weber, 2006). We will also consider the results of the survey in the context of findings from a similar simulation study on hurricane preparation and evacuation behavior in Florida, which suggests that prior outcomes affect the way that experience influences concern and evacuation behavior. References: Baker, E. (1991). Hurricane Evacuation Behavior. International J. of Mass Emergencies and Disasters, 9(2), 287-310. Kunreuther, H. (1984). Causes of Underinsurance against Natural Disasters. The Geneva Papers on Risk and Insurance, 9, 206-220. Kunreuther, H. (2006a). Climate Change, Insurability of Large-Scale Disasters, and the Emerging Liability Challenge. University of Pennsylvania Law Review, 155, 1795. Kunreuther, H. (2006b). Disaster Mitigation and Insurance: Learning from Katrina. The ANNALS of the American Academy of Political and Social Science, 604(1), 208-227. Packham, D. (1995). Evacuation in Wild Fires: The Australian Experience. The Australian Journal of Emergency Management, 10(1), 39-44. Weber, E. U. (2006). Experience-based and description-based perceptions of long-term risk: Why global warming does not scare us (yet). Climatic Change, 77(1), 103-120.