Pacific example - TTTSDK v3.1 distribution (Dec 2008, ITIC)
Hands-on exercise: Tsunami Travel Times (TTT software)
Sample Instructions for using ttt_auto
General Information:
NOAA’s National Geophysical Data Center, as the World Data Center (WDC-MGG) for Geophysics and
Marine Geology - Tsunamis, and the International Tsunami Information Center (ITIC), a NOAAUNESCO/IOC Partnership, are collaborating to provide, free of charge, tsunami travel time calculation
and display software to government organizations involved in providing tsunami warning and mitigation
services.
The Tsunami Travel Time software (TTT SDK v 3.1) was developed by Dr. Paul Wessel (Geoware,
http://www.geoware-online.com), and is used by the NOAA Pacific Tsunami Warning Center. The ITIC
and NGDC have purchased the TTT license to permit widespread free distribution. The public domain
mapping software Generic Mapping Tools (GMT) was developed by Drs. Paul Wessel and Walter Smith
To provide for easier calculation and map-making, the ITIC has provided a user-friendly .bat script
(Windows) named ttt_auto.bat that simplifies and automates the process. ttt_auto.bat creates a travel time
data file and two maps (ocean-wide and zoomed-in) using user-input information on the tsunami source
location (latitude and longitude), magnitude (assumed to be from an earthquake), source origin time, and
map region. ttt_auto.bat and its associated .bat scripts can be edited, thereby creating maps customized
according to a user’s needs. Information on the various parameters that can be changed can be found in
ttt_auto_README.doc
Usage:
1. Open Command Prompt and move to the “C:” drive
Type C: to changes drive from H: (or other default drive) to C:
If it is already C:, this step can be skipped.
2. Run ttt_auto.bat
Type ttt_auto
Enter latitude, longitude, magnitude and region
Enter whether to output travel time or estimated time of arrival (ETA) (1 = Yes, 0 = No)
If ETA is requested, enter the tsunami ‘origin time’ in format YYYY/MM/DD/HH/MN/SS
(Note: tsunami arrival times presently correctly calculated only for event years 1970-2038)
After calculating the travel times, plotting begins.
Enter whether to plot sea level stations (1 = Yes, 0 = No)
Enter whether to plot historical earthquakes (M > 6.0 in the past 100 years) (1 = Yes, 0 = No)
Example
Maps are shown on the following pages for the 1960 Chile EQ and tsunami. Source location is approximate.
Parameters used:
-- Latitude -38
-- Longitude -73.5
-- Magnitude 9.5
-- Region Pacific Ocean => type 3
-- For Tsunami Travel Times, type 0
Output Files:
After running ttt_auto.bat, a travel time or ETA data file) and plots are placed in a new sub-directory
C:\Program Files\TTT Package\Examples\TTT_AUTO_xxxxxx, where is xxxxxx
is the computer clock time (hr, min, sec) at the time the script is run.
Tsunami Travel Time (ETA)
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Pacific example - TTTSDK v3.1 distribution (Dec 2008, ITIC)
The tsunami travel times data file gives the station location, tsunami travel time, distance from the nearest
point on the grid to the station and uncertainty rates in sec/km for each location, as follows.
< travel_time_pac.txt >
Epicenter: LAT -38, LON -73.5
---LAT---||---LON---||--ARRIVAL--||---OFF---||---ERR--30.5500 152.1186 20h 53m 59s 12.648
2.83
48.9420 178.2700 19h 14m 06s
6.612
3.02
50.1720 171.8370 19h 49m 44s 10.656
2.75
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Station locations are from the input file (stations_ pac.txt)
Input file: < stations_pac.txt >
152.1186 30.5500 #21413
178.2700 48.9420 #21414
171.837 50.1720 #21415
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Example Maps
Examples for the 22 May 1960 event are provided on the following pages.
To further customize the automatically-made plots, refer to ttt_auto_README. Doc.
Customization is through edit of ttt_auto.bat and ttt_fancy_pac_auto.bat files.
ttt_auto_15m.ps
ttt_auto_15m.png
with historical EQs
w/o sea level stations
plot covering larger area
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Pacific example - TTTSDK v3.1 distribution (Dec 2008, ITIC)
ttt_auto_15m_zoom.ps
ttt_auto_15m_zoom.png
zoomed-in plot around source
with historical EQs
w/o sea level stations
default range
lat±30, lon ±40
map with historical EQs and sea level stations
map with sea level stations
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