ewttt

GSS plugin for Tsunami Travel Times computation using easyTTT

Description

The GSS simulation plugin simewttt estimates predicted tsunami travel times given an event represented by a point source (epicenter lat/lon) using the easyTTT code. Its output in TOAST comprises arrival lines and times in Map view as well as T1 time (exceedance of detection threshold) in Arrivals and Forecast Zones view.

easyTTT is not part of GSS. The author is Andrey Babeyko, GFZ German Research Center for Geosciences, Potsdam, babeyko@gfz-potsdam.de. However, GSS is delivered including the easyTTT binary ewttt and the plugin simewttt acting as interface between GSS and ewttt. In the TOAST simulation dialog the plugin is called EW TTT.

A file with the bathymetry has to be provided and configured.

Configuration

In order to be loaded by the GSS, the simewttt plugin needs to be added in the global section of the gss module (gss.cfg).

plugins = ${plugins},simewttt

The configuration of simewttt can be done using scconfig Modules ‣ gempa ‣ ewttt or by editing the configuration file ewttt.cfg.

Bathymetry

ewttt.bathymetry points to the bathymetry file in Golden Software Surfer 6 grid format.

Engine

ewttt.binary points to the ewttt executable file which is used as engine for the simulation.

Forecast points

Forecast point profiles can be registered as follows:

# Registration of a forecast point profile.
ewttt.forecastPoints = rtsp

For each entry of the list (comma-separated), there has to be a forecast point profile. The profile sets the filename of the forecast point file in DBF format.

# Absolute filename of the forecast point file in dBase format
ewttt.forecastPoints.rtsp.filename = @DATADIR@/toast/forecastzones/rtsp/6.0/cfp/CFP_Version_6p0.dbf

Use earthquake parameters

The plugin only uses latitude and longitude as input for the computation, and thus earthquake magnitude and depth are by default not associated with a simulation. In some uses cases, the user might want to have the association made. Set ewttt.useEqParams to true to do so. Note that in this case, for every different magnitude or depth a new simulation can be created.

Output

The simewttt simulation plugin produces tsunami arrival times for given locations and an arrival time grid.

The output directory is usually located at: ~/.seiscomp/toast/ewttt/output. A typical simulation directory looks like this:

`-- 83
   `-- 004006S
       `-- 100102E
           `-- 83004006S100102E6543c67e7e4a0474c85e96bf11829851ee2ba6
               |-- config.json
               |-- contours.txt
               |-- error.log
               |-- poi.summary
               |-- poi.xy
               |-- source.json
               |-- ttt.grd
               |-- ttt.log

The first level corresponds to magnitude, the second to latitude, the third to longitude and then follows the unique simulation ID. The different file types contain the following information:

config.json

contains simulation parameters used

contours.txt

contains the contour lines

error.log

contains the errors if the computation fails

poi.summary.txt

POI arrival times file

poi.xy

POI file used as input for ewttt

source.json

contains earthquake parameters, e.g., location and magnitude

ttt.grd

is the arrival time grid file

ttt.log

contains the executed command and the log output

Module Configuration

etc/defaults/global.cfg

etc/defaults/ewttt.cfg

etc/global.cfg

etc/ewttt.cfg

~/.seiscomp/global.cfg

~/.seiscomp/ewttt.cfg

ewttt inherits global options.

Note

Modules/plugins may require a license file. The default path to license files is @DATADIR@/licenses/ which can be overridden by global configuration of the parameter gempa.licensePath. Example:

gempa.licensePath = @CONFIGDIR@/licenses

ewttt.bathymetry

Default: @DATADIR@/ewttt/ttt_topo_10m.grd

Type: string

Path to EW TTT bathymetry file in Golden Software Surfer 6 grid format.

ewttt.binary

Default: @ROOTDIR@/bin/ewttt

Type: string

EW TTT executable.

ewttt.forecastPoints

Type: list:string

Registration of forecast points.

ewttt.maxTime

Default: 600

Unit: min

Type: int

Time span in minutes for which the arrival propagation is calculated.

ewttt.isoInterval

Default: 30

Unit: min

Type: int

Time span between the iso lines in minutes.

ewttt.output

Default: @CONFIGDIR@/toast/simewttt/output

Type: string

Base directory of EW TTT outputs.

ewttt.useEqParams

Default: false

Type: boolean

Add earthquake magnitude and depth to the simulation meta data. These parameters have no effect on the computation, as EW TTT only uses latitude and longitude as input. But for some use cases it might be useful to have this information associated with the simulation. If true, for every different magnitude or depth a new simulation can be created. If false, different magnitude or depth will all result in the same simulation.

Note

ewttt.forecastPoints.$name.* $name is a placeholder for the name to be used and needs to be added to forecastPoints to become active.

forecastPoints = a,b
ewttt.forecastPoints.a.value1 = ...
ewttt.forecastPoints.b.value1 = ...
# c is not active because it has not been added
# to the list of forecastPoints
ewttt.forecastPoints.c.value1 = ...

ewttt.forecastPoints.$name.filename

Type: string

Absolute filename of the forecast point file in dBase format.