In this paper, we address the problem of fast numerical simulation of tsunami wave propagation. In case of seismic event offshore Japan, tsunami approaches the nearest shore in approximately 20 minutes. Therefore, the warning system should operate even faster. The Mac-Cormack scheme was implemented at field programmable gates array (FPGA) microchip and tested against the known analytic solution. The numerical solution, obtained by FPGA method, has been compared to the one, issued by another algorithm. The expected performance will make it possible to calculate the basic wave parameters within a few minutes after earthquake.
An increase in the number of catastrophic floods of seismic nature has been observed within the last decades. Such events have an important impact on the population of littoral regions. Note that two years ago we commemorated 10 years from 2004 tsunami disaster of offshore Sumatra Island (Indonesia) that had caused hundreds of thousands of casualties. In 2016 Japan commemorated 5 years of the Great Tohoku Earthquake and tsunami of March 11, 2011, which resulted in economy loss of ¼ of annual Japan budget and had a considerable impact on the entire world economy (in particular, Germany decided to abandon the use of nuclear energy because of the accident at Fukushima-1 nuclear power station). This was one of the strongest earthquakes in the country history. Tsunami waves swept out buildings and vehicles. According to evaluation of the German Center for Disaster Management and Risk Reduction, human loss was compared to 20.000 and about 1.000.000 persons forfeit their houses (Economic losses from earthquakes and natural disasters peaked in 2011. URL: http://earthsky.org/earth/economic-losses-from-earthquakes-and-natural-disasters-peaked-in-2011 access date: 15.06.2016).
Overall economy loss is evaluated from 250 to 309 billions of USD. It happens that our modern society is not prepared to disasters of seismic nature of such scale.
Modern tools for computer modeling make it possible to provide a rather precise calculation of at least the first wave period provided that the initial wave shape at tsunami source is given (the sea bed displacement at source). However, the time required to deliver the robust prediction of the wave parameters is among the core characteristics of any tsunami warning system. In case of Japan, typical time for tsunami wave to approach the nearest coast is close to 20 minutes. Therefore, as it is not possible to predict the time and the magnitude of a forthcoming earthquake, tsunami warning system should operate practically in a real-time mode after the seismic event. The presented paper is devoted to performance optimization of Tsunami Early Warning Systems (TEWS), namely to speed up the calculation of the wave front and wave heights along the entire coast line considered.
