Decision analysis for a tsunami detection system – case study: Sri Lanka

Abstract

The massive devastation of the Indian Ocean mega tsunami in 2004, clearly calls for an efficient early warning system for the Indian Ocean countries. The ‘Regional Watch Provider’ system currently planned makes some countries entirely dependent on the watch providers. We discuss a feasible and reliable tsunami detection mechanism for Sri Lanka that would give it some independent information for decision making purposes. It contemplates Sri Lanka deploying its own additional detection tools. A stand-alone tide gauge system, a buoy system and a combined gauge and buoy system are tested with the status quo or ‘do nothing’ alternative. A decision analysis exercise investigates the probability of tsunamis, probability of failures of each detection system, the probability of successful completion of an evacuation and the probability of false warnings which have their own costs. This paper concludes with the derived recommendations for a preferred tsunami detection system for Sri Lanka.

Keywords:

• tsunami
• warning
• evacuation
• decision analysis

Acknowledgements

Authors wish to thank Pacific Tsunami Warning Centre (Hawaii) and the DMC (Sri Lanka) for providing invaluable information for this study. Further, the copy right permission granted by ‘Owl and Mouse Software’ to reproduce their material is thankfully acknowledged.