There is still no tsunami warning systemprotecting the shores of the Indian Ocean, but imagine that a tsunami warning system had been in operation at the time of the 2004 Indian Ocean Tsunami. What disaster management information would have been issued for this tsunami ? This paper first proposes four tsunamimodels based on the earthquake information issued by different institutions. Next, setting these tsunami models as the initial condition, tsunami simulations are conducted to find the height of the tsunami striking the coastline around the Indian Ocean. As a result, it is indicated that because the tsunami model immediately after occurrence of the 2004 Sumatra Earthquake and the Indian Ocean tsunami calculated from this model are underestimated, appropriate tsunami warnings would most probably not have been issued before the 2004 tsunami struck land.

1. [1] S. Koshimura, M. Takashima, S. Suzuki, H. Hayashi, F. Imamura, and Y. Kawata, “Estimation of the Possible Tsunami Disaster Potential within the Indian Ocean,” Annual Journal of Coastal Engineering, JSCE, Vol.52, pp. 1416-1420, 2005 (in Japanese).
2. [2] L.Mansinha and D. E. Smylie, “The displacement fields of inclined faults,” Bulletin of the Seismological Society of America, Vol.61, No.5, pp. 1433-1440, 1971.
3. [3] H. Matsutomi, T. Takahashi, M. Matsuyama, K. Harada, T. Hiraishi, S. Supartid, and S. Naksuksakul, “The 2004 Off Sumatra Earthquake Tsunami and Damage at Khao Lak and Phuket Island in Thailand,” Annual Journal of Coastal Engineering, JSCE, Vol.52, pp. 1356-1360, 2005 (in Japanese).
4. [4] Y. Suzuka, T. Takahashi, and H. Matsutomi, “Numerical Simulation on the Sumatra Earthquake Tsunami along the Southwest Coast of Thailand,” Annual Journal of Coastal Engineering, JSCE, Vol.52, pp. 1341-1345, 2005 (in Japanese).
5. [5] S. Takahashi, T. Takahashi, S. Kojima, and T. Konuma, “Fundamental Study on Tsunami Source Detection by using Long-Range Ocean Radar with Back Scattering Strength as Detection Index,” Annual Journal of Coastal Engineering, JSCE, Vol.54, pp. 206-210, 2007 (in Japanese).
6. [6] T. Tomita, T. Arikawa, M. Yasuda, F. Imamura, and Y. Kawata, “Field Survey around South West Coast of Sri Lanka of the The December 26, 2004 Earthquake Tsunami Disaster of Indian Ocean,” Annual Journal of Coastal Engineering, JSCE, Vol.52, pp. 1406-1410. 2005 (in Japanese).
7. [7] D. L. Wells, and K. J. Coppersmith, “New Empirical Relationships among Magnitude, Rupture, Length, Rupture Width, Rupture Area and Surface Displacement,” Bulletin of the Seismological Society of America, Vol.84, No.4, pp. 974-1002, 1994.