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ness of at-risk populations after a series of recent tsunami outreach efforts in Seaside, Oregon
(Box 3.3; Connor, 2005).
Knowledge assessments of the at-risk population can also be used for determining the
effectiveness of warning systems. For example, a survey of 956 individuals from across Hawaii
found that 59 percent of respondents did not understand the meaning of the tsunami-alert
sirens, even though 69 percent of respondents also said that some sort of oficial warning
would be their signal to evacuate from a tsunami (Gregg et al., 2007). Similar confusion of
what sirens signify has been expressed during educational workshops in Hawaii (Alexandra et
al., 2009). Surveys of Hilo, Hawaii, residents who survived the 1960 tsunami indicate that only
40 percent of people who heard warning sirens evacuated, whereas many people waited for
additional information from other information sources (e.g., television, relatives) before evacu-
ating (Bonk et al., 1960; Lachman et al., 1961). A survey of 2004 Indian Ocean tsunami survivors
in Padang, West Sumatra, indicates that the majority of people received information through
social networks and not through oficial channels (Birkman et al., 2008).
These isolated case studies highlight the need for additional perception, knowledge, and
preparedness surveys of at-risk populations to assist in developing and implementing effec-
tive education efforts, particularly in communities that are threatened by near-ield tsunamis
because of the lack of adequate warning time. The committee commends the NTHMP for citing
the need for evaluations and surveys to determine the effectiveness of tsunami education
products and the level of preparedness of at-risk populations in its draft 2009-2013 strategic
plan. The committee encourages the NTHMP to focus future preparedness assessments on
communities threatened by near-ield tsunamis, where successful evacuations will be more
the result of a well-informed population taking self-protective actions and less from oficial
response procedures.
Conclusion:
For far-ield tsunamis, successful evacuations will depend on at-risk
individuals understanding oficial warnings and following instructions given by local
agencies. For near-ield tsunamis, successful evacuations will depend on the ability of at-
risk individuals to recognize natural cues and to take self-protective action. The committee
concludes that previous knowledge gained through sustained education efforts will likely
play a larger role in saving lives from near-ield tsunamis than warnings issued by the
tsunami warning centers, given the current scientiic and technological constraints on
issuing warnings fast enough. Regardless of the kind of tsunami, understanding the needs
and abilities of at-risk populations is a critical element in developing effective education.
Although numerous isolated studies have been conducted in coastal communities,
the NTHMP has not systematically assessed the perception, knowledge, and levels of
preparedness of at-risk individuals. Lacking this information, the NTHMP has limited
baseline information from which to gauge the effectiveness of education efforts, to tailor
future efforts to local needs, or to prioritize limited funds.
Recommendation:
Faced with limited resources, the NTHMP should give priority to
systematic, coordinated perception and preparedness studies of communities with near-
