Dimri has raised two significant questions. The first is about the directivity of tsunamis and the other about legal aspects of forecasting earthquakes and tsunamis. As far as directivity of tsunami waves is concerned, the matter is quite simple for seismologists. In general, it may be remembered that the occurrence of tsunamis is a result of a large-magnitude earthquake. The large geological or tectonic faults in the Sumatran and Andaman regions are quite well known. These faults have generated a number of moderate to large magnitude earthquakes during the last 100 years or so. If we know the fault plane solutions of these past historical seismic events, then the potential direction of tsunami waves could be easily determined. As a thumb rule it may be remembered that amplitude and energy of tsunami waves are minimum in the direction of rupture, whereas they are highest at right angles to the direction of rupture. This is explained with the example from the 26 December 2004 earthquake and relatedtsunami.
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