Dealing with Natural Disasters: Preparedness versus Post-Event Response

Abstract:

Management or mitigation of natural disasters is comprised of two distinct elements: disaster preparedness and disaster response. Fundamentally disasters fall into two categories: 1) those whose timing can be predicted and evaluated in advance, such as hurricanes, floods, tsunamis, or even sea level rise; and 2) those that can be anticipated based on analysis, but their exact timing is unknown, such as earthquakes and landslides. Consequently, the type of response and options available for scientific and engineering consultation are fundamentally different.

The common aspects of all natural disasters is that there is evidence of past events either historical or geologic, or both. Thus, given past evidence, scientists and engineers have an opportunity to recommend and guide development and implementation of long term or permanent mitigation measures, such as improving the resiliency of the infrastructure and emergency preparedness. However, the appropriate mitigation measures are very much a function of the type of event. Severe atmospheric events, such as hurricanes, typically can be predicted several days in advance and scientists and engineers have a role in guiding preparation of specific additional, temporary, mitigation measures and selective evacuation, as appropriate. In contrast, while earthquake potential of a given region may be well recognized, the actual timing of the event is an unknown and, consequently, the primary defense is in developing sufficiently resilient infrastructure which can be enhanced with early warning systems. Similarly, the type of damage caused by flooding, e.g. hurricane and tsunami, is significantly different from the type of damage caused by an earthquake in that flooding damage is pervasive affecting large contiguous areas wiping out all infrastructure whereas earthquake or landslide damage tends to be clustered with many elements of infrastructure remaining fully or somewhat operable. This distinction is very important when it comes to the type of technical guidance that is needed following such events.

This presentation highlights lessons learned from post-event reconnaissance as a part of the NSF-funded Geotechnical Extreme Event Reconnaissance (GEER) over the last two decades.