In order to create a prototype of
tsunami database for tsunami early warning system with data assimilation in
Malaysia, we located 16 source points in total around the Andaman Sea with 4
magnitudes (M_{w}6.5, 7.0, 7.5 and 8.0) and 4 depths (0, 10, 20 and 30
km). The coastal and forecast points are located along the Malaysian coastal
area at 1 m and 30, 40, 50 and 60 m of bathymetric contour depth with random
interval distance, respectively. In numerical simulation, TUNAMI-N2 (Tohoku
University’s Numerical Analysis Model for Investigation of Near-field tsunamis,
No.2) is used to calculate the tsunami waveforms at the output points. Tsunami
arrival times at the coastal points are calculated using inverse tsunami travel
time by TTT (Tsunami Travel Time). Tsunami database was constructed by using
MySQL database which contains of 256 scenario earthquakes that cover
historically most active subduction zone around the Andaman Sea. The nearest
surrounding data points of a determined hypocenter can be retrieved from
database by interpolation, extrapolation and two maximum risk methods. In
tsunami data assimilation, TUNAMI-F1 (Tohoku University’s Numerical Analysis
Model for Investigation of Far-field tsunamis, No.1) is used to calculate the
tsunami waveforms at the buoy station of Malaysia. Green’s functions, which are
calculated tsunami waveforms from faults assigned 1.0 m of slip, are prepared
for 16 model sources. In two inversion tests, the initial conditions are
precisely resolved by non-negative least squares method. For inversions of two
real cases, the slip is almost resolved at the nearest fault and has shown
instability in slip distributions for whose epicenter is located closer and
slightly out from model sources, respectively.