Information for Natural Disaster Loss Reduction

Robert M. Hamilton

Representing U.S. National Academy of Sciences

Reducing the risks and impacts of natural disasters requires reliable information. This information is needed to:

• Avoid hazards through land-use planning
• Resist the effects of hazards with building practices
• Evacuate dangerous areas with effective warning systems
• Reduce the socio-economic impacts and share the losses through insurance and government assistance.

The area of risk assessment is central to developing and implementing government policies for loss reduction. Risk depends on an assessment of the likelihood of hazard occurrence and the vulnerability of population and structures. Therefore, demographic data, including future projections, are critical to risk assessment. In addition, data are required about the fragility of the various classes of structures. This includes estimates of the probability of damage at increasing levels of stress induced by a natural hazard. Such information can be acquired from post-disaster damage surveys or from laboratory testing.

Information about disaster losses, however, is generally deficient in many ways, which can make risk assessments highly uncertain. The most reliable information is usually in the area of human losses, although even these numbers can be poorly known. In the area of structural losses, often the best estimates are based on insurance claims and on the amount spent for government assistance. Such direct losses, though, can be exceeded by so-called indirect losses, which include loss of employment, economic setback, social and political destabilization, and other factors. Losses of this nature are almost impossible to quantify, but improved understanding of their general causes and impacts is critical.

Scientific and engineering organizations play important roles in developing information for risk assessment by assisting in setting data standards, identifying data needs, promoting data acquisition, and participating in pre-disaster planning and post-disaster surveys. A potential activity for the Inter-academy Panel’s committee on natural disasters would be to review these roles and identify areas that would warrant increased effort at the regional or international level.