Tsunami Detection and Warning Capability Using Nearshore Submerged Pressure Transducers — Case Study of the 4 October 1994 Shikotan Tsunami

Coastal communities require reliable, accurate, and timely warning of approaching tsunamis. Presently, warnings of a potential tsunami rely on the detection of a seismic disturbance with a submarine epicenter. However, the ability to quantitatively predict the tsunamigenic potential from seismic signals has not been demonstrated. Mid-ocean, bottom mounted pressure sensors could provide advance warnings for the coastal areas far from the source (far-field tsunamis) if the signals were available in near real time (F. Gonzales, personal communication). While such sensors represent a vast improvement over current practices, since the generation of a tsunami is verified, the measured mid-ocean amplitude is quite small. The critical information is the eventual amplitude of the tsunami run up at points along the affected coastline; these values can be highly variable spatially. Validated transformation models, using the mid-ocean tsunami signal as input, may provide an effective warning for those situations.