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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS002 Oral Presentation 1736
A Comparison Study of Two Numerical Tsunami Forecasting Systems
Dr. Diana Greenslade
Bureau of Meteorology Research Centre Australian Bureau of Meteorology IASPEI
Vasily Titov
Recent tsunami events, e.g. Sumatra 2004 and Java 2006 have demonstrated the need for providing
accurate and timely tsunami warnings. Improvements in the availability of sea-level observations and
advances in numerical modelling techniques are increasing the potential for tsunami warnings to be
based on numerical model forecasts. Numerical tsunami propagation and inundation models are well
developed, but they present a challenge to run in real-time; partly due to computational limitations and
also due to lack of detailed knowledge on the earthquake rupture details. For these reasons, current
tsunami forecast systems are based on pre-computed tsunami scenarios. A tsunami scenario is a single
tsunami model run that is calculated ahead of time with the initial conditions carefully selected so that
they are likely to represent an actual tsunamigenic earthquake. This paper will present a comparison of
two tsunami scenario databases: the NOAA/PMEL system, currently being implemented at NOAA
Tsunami Warning Centers and the Bureau of Meteorology system, which is being developed for the
Australian Tsunami Warning System. Both scenario databases are based on the MOST numerical model,
but there are some differences in the way the scenarios are constructed. The databases will be
described, and a comparison of results for the Tonga event (May 3, 2006) will be presented. The
tsunami forecasts will be compared to each other and to available observations, including those from
two DART buoys located near Hawaii.
Keywords: tsunami, forecast, modelling