1. How the Indian Ocean tsunami warning
system works
s1180028
Naohiro Nakamura

2. Overview
● Introduction
● India before 2004
● Here is how the system works - 1
● Here is how the system works - 2
● How to make announcement to populations
● Conclusion

3. Introduction
A tsunami in the Indian Ocean killed almost
230,000 people in 2004.
↓
The United Nations Intergovernmental
Oceanographic Commission began coordinating
efforts to create an Indian Ocean tsunami early
warning system.

4. India before 2004
● There were no sea-level monitoring
instruments
● Many countries did not have agencies
responsible for tsunami warnings
● Many countries did not have points of contact
to receive messages from international warning
centers
● In recent years, Indian prepare the tsunami
warning system

5. Here is how the system works - 1
● An earthquake strikes in the Indian Ocea
● Data from a variety of sources are transmitted
to the PTWC based in Hawaii and the JMA in
Tokyo.
● These two centers determine whether they have
the potential to produce tsunamis and predict
tsunami wave arrival times wherever possible
PTWC : Pacific Tsunami Warning Center
JMA : Japan Meteorological Agency

6. Here is how the system works - 2
● Many national agencies have received their
own information, from local or regional
seismic centers, buoys, news bulletins and so
on.
● Information will be fed back and forth between
Hawaii, Japan and the region.
● Warnings to the population by many different
routes

7. How to make announcement to populations
● radio ● bells
● television ● megaphone
● SMS ● loud-speakers
● email
In some countries, well-rehearsed drills will kick
in and local agencies will coordinate an
evacuation.

8. Conclusion
Through the experience in 2004, tsunami
warning system is created.
Tsunami warning is determined from
observed data, and warnings to the
population by many different routes.
By grace of this system, death toll from
tsunami disaster will decrease.