Kawasaki, Japan:  International Research Institute of Disaster Science (IRIDeS), Tohoku University and Fujitsu Laboratories Ltd. today announced their joint development of a high-resolution tsunami model, able to run on a supercomputer, and based on Tohoku University’s existing TUNAMI-N2(1) simulation model, which is in widespread use internationally. For this project, IRIDeS prepared the model to perform high-resolution calculations, and Fujitsu Laboratories implemented methods for high-efficiency parallelization.

The Great East Japan Earthquake far exceeded the scale of previously envisioned earthquakes, causing underestimations of tsunami height made three minutes after the start of the earthquake, exposing an urgent need to improve methods of real-time estimation. The disaster also illustrated the need for information beyond wave height, such as the scope of flooding. Now Tohoku University and Fujitsu Laboratories have developed a tsunami model that quickly predicts the extent of flooding from sea surface deformation, which is the source of the tsunami and is estimated based on observation data on the shape of the tsunami out at sea and on tectonic shifts onshore at the time of the earthquake. For example, flooding in the Great East Japan Earthquake started in Sendai one hour after the earthquake struck. With this technology basic predictions of where flooding would occur in the City of Sendai can be provided in about 10 minutes for the Great East Japan Earthquake case.

By making high-resolution, real-time predictions of general tsunami-flooding conditions, Tohoku University and Fujitsu Laboratories will contribute to more effective disaster-response measures.

This research was published on February 24th in an online preview of Geophysical Research Letters, a journal of the American Geophysical Union.