Geoscience Reference
In-Depth Information
proximation of economic exposure, these reports also include inventories of the amount and
percentage of tax-parcel values, employee distributions, and business sales volume in tsunami
hazard zones of each community and county. In reviewing the tsunami and risk/vulnerability
assessment sections of several FEMA-approved state mitigation plans, the committee found
little information related to the diversity of populations in tsunami-prone areas of the various
coastal states. Some state plans estimate the number of individuals in tsunami hazard zones
of each county, some simply list the communities with populations with tsunami risk, and
some only discuss general tsunami-related population issues. Many plans, however, did include
detailed information on inancial, structural, and critical facility exposure, suggesting that plans
are written to help document potential long-term economic impacts and not preparedness
issues to save lives.
Conclusion:
There is no national assessment of population exposure and sensitivity to
tsunamis, including the number and types of individuals in tsunami hazard zones. The
NTHMP's current subcommittee structure (Mapping and Modeling, Warning Coordination,
and Mitigation and Education) does not coordinate mapping the exposure of at-risk
individuals and communities and therefore does not provide leadership on this topic. The
absence of this information and the leadership to attain it impacts national preparedness
to tsunamis in several ways. First, the NTHMP will be unable to reach its stated goal of
a national tsunami risk assessment (see earlier conclusion in this chapter on this topic).
Second, efforts to develop realistic evacuation plans are compromised in communities
threatened by far-ield tsunamis if the magnitude of the at-risk population is not known.
Third, communities threatened by near-ield tsunamis cannot develop public awareness
and education efforts that are tailored to local conditions and needs (discussed in the
following chapter) without an understanding of the types of at-risk individuals.
Recommendation:
The NTHMP should collaborate with state and federal agencies (e.g.,
the USGS, the Census Bureau) to periodically inventory the number and types of people
in tsunami hazard zones at intervals no less frequently than that of the U.S. Census, with
special attention to children, the inirm, tourists, and other groups whose heightened
sensitivity to tsunamis could constrain their ability to prepare for and evacuate from future
tsunamis. The NTHMP should expand Mapping and Modeling Subcommittee efforts to
explicitly include community vulnerability. The NTHMP should establish a Science Advisory
Committee to help develop guidelines on consistent approaches for identifying and
mapping populations in tsunami-prone areas. The NTHMP should also provide guidelines
on how to use this information to tailor evacuation planning and education efforts.
Evacuation Potential
In addition to population exposure and sensitivity, an individual's capacity to learn from
past disasters, implement risk reduction measures, adapt during an event, and persevere after an
