HR: 13:40h
AN: S13C-01 INVITED [Abstracts]
TI: Digging Our Own Holes: Institutional Perspectives on Seismic Hazards
AU: * Stein, S
EM: seth@earth.northwestern.edu
AF: Northwestern University, Department of Geological Sciences, Evanston, IL 60208
United States
AU: Tomasello, J
EM: JT@REAVESFIRM.COM
AF: The Reaves Firm, 5118 Park Ave., Suite 400, Memphis, TN 38117
United States
AB:
It has been observed that there are no true students of the earth; instead, we each dig our own holes and sit in them. A
similar situation arises in attempts to assess the hazards of earthquakes and other natural disasters and to develop
strategies to mitigate them. Ideally, we would like to look at the interests of society as a whole and develop strategies
that best balance hazard mitigation with alternative uses of resources. Doing so, however, is difficult for several reasons.
First, estimating seismic hazards requires assumptions about the size, recurrence, and shaking from future earthquakes, none
of which are well known. Second, we have to chose a definition of seismic hazard, which is even more arbitrary and at least
as significant about future earthquakes. Third, mitigating the risks involves economic and policy issues as well as the
scientific one of estimating the hazard itself and the engineering one of designing safe structures. As a result, different
public and private organizations with different institutional perspectives naturally adopt different approaches. Most
organizations have a single focus. For example, those focusing on economic development tend to discount hazards, whereas
emergency management groups tend to accentuate them. Organizations with quasi-regulatory duties (BSSC, FEMA, USGS) focus on
reducing losses in future earthquakes without considering the cost of mitigation measures or how this use of resources should
be balanced with alternative uses of resources that could mitigate other losses. Some organizations, however, must confront
these tradeoffs directly because they allocate resources internally. Hence hospitals implicitly trade off more earthquake
resistant construction with treating uninsured patients, highway departments balance stronger bridges with other safety
improvements, and schools balance safer buildings with after school programs. These choices are complicated by the fact that
such infrastructure typically has longer life than normal commercial or residential buildings, and the direct and indirect
losses resulting from their failure can be much larger. Hence the issue is balancing mitigating large losses in infrequent
disasters with smaller but steady losses that may over time be greater. Finally, there has been little investigation of the
benefits of mitigation regulations on the private sector relative to their consequences, which may significantly increase
building costs, require seismic retrofits, and cause difficulties in securing loans and insurance. Possible outcomes include
reduced economic activity (firms don't build or build elsewhere), job loss (or reduced growth), and the resulting reduction
in tax revenue and thus public services. Given these complexities, organizations should be encouraged to examine broader
societal issues beyond their institutional perspectives, and significant efforts should be made to develop a more integrated
approach.
UR: http://www.earth.northwestern.edu/people/seth/Texts/nmszeos.pdf
DE: 7212 Earthquake ground motions and engineering seismology
SC: Seismology [S]
MN: Fall Meeting 2005