PERCEPTIONS OF RISK AND UNCERTAINTY

Individuals, institutions, and entire sectors often do not perceive that hazards pose unacceptable risk or that they may have a responsibility—or even the capacity—to reduce the risk. Successful resilience-focused private–public collaboration depends partially on increasing the transparency and general knowledge of risk and uncertainty. Successful collaborative strategy-building attempts to account for the lack of understanding among community members of what constitutes an extreme event and the perception that an extreme event will not affect an individual personally.

Perception is the basis of action, and inaccurate perceptions stand in the way of concerted action to promote community disaster resilience. Individuals, groups, and societies have great difficulty in understanding and acting on information related to low-probability–high-consequence events. Understanding risk is conceptually difficult and subject to biases, including focused attention on a recent or dramatic event (often to the exclusion of more probable events) or expectations about future events based on past events. As an example of the latter bias, in the case of Hurricane Katrina, evidence indicates some New Orleans minority residents chose not to evacuate their homes in spite of a mandatory evacuation order because of past experience with Hurricanes Betsy and Camille (Elder et al., 2007). They reasoned that because they were safe at home during previous storms, there would be little danger for them from Katrina; how much worse could Katrina be?

Time horizons also affect perception of risk. People may believe that a major disaster is likely to occur but not in their own lifetimes. And individuals and institutions may have the tendency to think and plan in terms of relatively short periods. That may be part of the reason why political leaders discount the future benefits of making their communities more resilient to rare events, especially if their terms in office are relatively short. Without a motivating sense of urgency, the benefits of participating in collaborative efforts may not be appreciated. Even if there is a general sense of the likelihood of a particular type of disaster, such as Californians’ wide recognition of the likelihood of earthquakes, people may find it difficult to believe that such an event will affect them personally.

Another challenge to be considered in developing collaborative strategies is related to people’s general inability to grasp the concept of uncertainty. Predictions about the future—including likelihood of disasters—always contain elements of uncertainty. However, when uncertainties appear unacceptably large, people will not act or will postpone taking action. For example, two key elements in the inability of the public and of institutions to appreciate and act on climate change are the uncertainties surrounding projections of the effects of climate change and the uncertainties related to projections on meaningful geographic and time scales (NRC, 2009). The same is true for other types of hazards: when the perceived uncertainty associated with an event and its consequences is high, action is difficult to justify.



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