**1. Introduction**

Confirmed tsunami events from 1610 BC to AD 2014 are 1212 events from which 245 were deadly. The geographical distribution of these events is 76% in the Pacific Ocean, 9% in the Indian Ocean and Red Sea, 6% in the Atlantic Ocean and Caribbean Sea and 9% in the Mediterranean Sea. Concerning the sources for generation of the tsunamis, 87% are from earthquake, 8% from underwater volcanic eruptions, 4% from major ocean landslides and 1% from other sources [1].

In recent years, world has experienced few mega-tsunamis, which have caused extensive loss of life and properties. The most destructive ones were in December 2004 in Sumatra causing more than 290,000 death and March 2011 in Japan, creating a nuclear accident [2]. The event of 2004 has triggered many global initiatives, such as a new tsunami detection system, more detail coastal modeling, tsunami compatible coastal developments, integrated approach for region‐ al early warning system (EWS) and public educations, awareness and preparedness.

Early warning system (EWS) can play an important role in risk reduction, using the effective development of national and local capabilities. However, it must be emphasized that national risk reduction strategies must not only be based on the EWS. If risk considerations are not adequately factored into national development strategies, disaster occurrence and loss will continue to increase, with or without the improved EWS capabilities. EWS should thus be seen as a last line of defense for dealing with unmanaged risks. EWS should be developed as vital element of much wider national risk management and reduction strategies. If the EWS is developed as stand-alone systems, it may contribute to generate a false sense of security leading to indifference and passivity in vulnerable groups and sectors as well as among national disaster management agencies and systems.

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