NUMERICAL SIMULATIONS FOR TSUNAMI FORECASTING AT PADANG CITY USINGOFFSHORE TSUNAMI SENSORS
By SETYOAJIE PRAYOEDHIE (Tsunami Course, 2010)
Indonesian Agency for Meteorology Climatology, and Geophysics (BMKG), Indonesia.
1. Fault parameters of tsunami sources
Table 1. Fault parameters for all scenarios.

133636666666677478387375
5000Figure 1. Subfault model for scenario 2. The green rectangles shows the different
sizes of fault segments for scenario 2 with slip varying between 4 and 8 m.
Yellow boxes within the fault areas shows the assumed sub fault with
50 km x 50 km size and 1 m slip. The number within every subfault
is a slip amount. The green diamonds are the locations of the offshore
tsunami meters while pink diamonds are the locations of coastal output points.

22. Location of off shore tsunami meters

Figure 2. Location of offshore tsunami meters around Sumatra island.
Rectilinear boxes is the computation area.

Table 2.

Location of output points and water depth measured using bathymetry data from GEBCO.

3Tsunami Height (meter)

3. Result (Tsunami Height)
0.5

TM10-0.5

TUNAMI-F TM1-Bathy 1m
TUNAMI-N2 TM1-Bathy 1m
TUNAMI-N2 TM1-Bathy 30c-1-1.5030

6090120150180

Tsunami Height (meter)

Time (minute)
1.6

TM21.1TUNAMI-F TM2-Bathy 1m
TUNAMI-N2 TM2-Bathy 1m
TUNAMI-N2 TM2-Bathy 30c

0.6
0.1-0.4-0.9030

6090120150180

Tsunami Height (meter)

Time (minute)

0.3

TM30.20.1

TUNAMI-F TM3-Bathy 1m
TUNAMI-N2 TM3-Bathy 1m
TUNAMI-N2 TM3-Bathy 30c0-0.1-0.2-0.3

Tsunami Height (meter)

0306090
Time (minute)

0.2

120150180

TM40.10-0.1

TUNAMI-F TM4-Bathy 1m
TUNAMI-N2 TM4-Bathy 1m
TUNAMI-N2 TM4-Bathy 30c-0.2-0.3
0306090
Time (minute)120150Figure 3. Comparison of the tsunami waveforms for offshore output points
calculated through numerical simulation using TUNAMI-N2 and TUNAMI-F1
source codes with different bathymetry.

4180

20-2-4-6 0Tsunami Height (meter)

Tsunami Height (meter)

4Tsunami Height (meter)

OP1306090 120Time (minute)

2150

180

OP310-1-2-3030

6090

120

150

6420-2-4-6OP2030

180-1-2-330

60

90120150180Time (minute)

Tsunami Height (meter)

Tsunami Height (meter)

00120

150

180150180150180

10-1-2030

6090120

Time (minute)

OP5190OP42Time (minute)

260

Time (minute)

Tsunami Height (meter)

62OP610-1-2-3030

6090120

Time (minute)

Figure 4. Comparison of the tsunami waveform calculated through a numerical simulation
using TUNAMI-N2 and TUNAMI-F1 source code for different bathymetry data for coastal
output points. Blue lines show the tsunami waveforms calculated using TUNAMI-F1 for
1 arc-minute bathymetry data, the red lines show the tsunami waveforms calculatedusing TUNAMI-N2 for 1 arc-minute bathymetry data,the green lines show the tsunami
waveforms calculated using TUNAMI-N2 for 30-arc second bathymetry data.

5

Initial Tsunami Height (meter)

2
BATHYMETRY 1 ARC MINUTE TUNAMI-N2

1.5

BATHYMETRY 1 ARC MINUTE TUNAMI-F1
BATHYMETRY 30 ARC SECONDS TUNAMI-N210.50-0.5-1TM1TM2TM3TM4

OP1 OP2 OP3Output Points

OP4OP5OP6Figure 5. Comparison of the initial tsunami height of synthetic waveform obtained
through a numerical simulation using TUNAMI-N2 and TUNAMI-F1 source code foroffshore output points (TM1-TM4) and coastal output points (OP1-OP6)
with different bathymetry data.

4. Conditions for Computation
Table 3. Region for computation and data used for simulation.
Area

94°E-103°E / 1°N-8°S

Bathymetry Data

1 arc-minute GEBCO and 30 arc-minute GEBCO∆t

3.0s (1 arc-minute GEBCO) and 2.0s (30 arc-minute GEBCO)

6