What are the effects of tsunamis?

Question

the 2004 indian tsunami affected a lot of people. what can be done to prevent tsunamis?

Answer 1

Nowadays they are called seismic waves, and nothing can be done to "prevent" them.

However, the 2004 event was a wake up call for a lot of countries that better prediction and warning systems need to be in place.

Since seismic waves travel at predictable speeds, it is possible to put sensors out in the ocean a measured distance away from shore, so that when an earthquake happens, the sensors will pick up whether or not that earthquake has produced a seismic wave (because not all earthquakes do) and report critical information such as which direction that wave is traveling and how powerful it is. Such a system could give coastal communities as much as a few hours warning to evacuate.