Tsunami alert efficiency

“Tsunami Alert Efficiency” is the rapid, accurate and reliable conduct of tsunami warning messaging, from the detection of potential tsunamigenic earthquakes to dissemination to all people under threat, and the successful survival of every person at risk on the basis of prior awareness and preparedness. Lessons learnt from recent disastrous tsunamis point towards significant gaps between the science behind tsunami warning and the practice of saving lives and minimizing risk. Most notable was the identification of the 26 December 2004 Sumatra Mw 9.1 tsunamigenic earthquake in near real time, and due to the lack of communication means and unpreparedness there was no way to alert the circum-Indian Ocean inhabitants. Con- sequently, a quarter of million people lost their lives. This catastrophe was considered an “eye-opener”, showing that, clearly, although tsunamis cannot be prevented, the massive loss of lives was avoidable and the scope of damages was mitigable.

This paper describes the leading concepts behind the tsunami alerting process, emphasizing the importance of the corresponding awareness and preparedness, and discuss the difficulties and uncertainties that may downgrade its efficiency, because the effective conduct of the alerting process is the ultimate key to saving lives under threat. We aim not to rephrase existing SOPs or user guides, but bring to mind some thoughts on making tsunami alerts more efficient and effective.