The current tsunami warning system also relies on
quick analysis of seismic data. The recent deployment of
advanced seismological analysis methods for rapid determination
of earthquake source parameters, such as the W
phase analysis, makes it possible to quickly assess an
earthquake’s size with acceptable accuracy and to estimate
the potential tsunami size, in order to issue tsunami
warnings in less than half an hour for global earthquakes.
For example, during the 2012 Sumatra earthquake, PTWC
issued bulletins with not only earthquake parameters but
also tsunami amplitudes predicted by simulation-based
empirical formula. Thus tsunami warning is practically
possible at least for far-field tsunamis. Accurate
near-filed tsunami warning is still challenging as discussed
in next sections.