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Titel |
Computerized Workstation for Tsunami Hazard Monitoring |
VerfasserIn |
Mikhail Jr. Lavrentiev, Andrey Marchuk, Alexey Romanenko, Konstantin Simonov, Vasiliy Titov |
Konferenz |
EGU General Assembly 2010
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Medientyp |
Artikel
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Sprache |
Englisch
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Digitales Dokument |
PDF |
Erschienen |
In: GRA - Volume 12 (2010) |
Datensatznummer |
250034085
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Zusammenfassung |
We present general structure and functionality of the proposed Computerized Workstation for
Tsunami Hazard Monitoring (CWTHM). The tool allows interactive monitoring of hazard,
tsunami risk assessment, and mitigation – at all stages, from the period of strong
tsunamigenic earthquake preparation to inundation of the defended coastal areas. CWTHM is
a software-hardware complex with a set of software applications, optimized to
achieve best performance on hardware platforms in use. The complex is calibrated for
selected tsunami source zone(s) and coastal zone(s) to be defended. The number of
zones (both source and coastal) is determined, or restricted, by available hardware
resources.
The presented complex performs monitoring of selected tsunami source zone via the
Internet. The authors developed original algorithms, which enable detection of
the preparation zone of the strong underwater earthquake automatically. For the
so-determined zone the event time, magnitude and spatial location of tsunami source are
evaluated by means of energy of the seismic precursors (foreshocks) analysis. All
the above parameters are updated after each foreshock. Once preparing event is
detected, several scenarios are forecasted for wave amplitude parameters as well as the
inundation zone. Estimations include the lowest and the highest wave amplitudes and
the least and the most inundation zone. In addition to that, the most probable case
is calculated. In case of multiple defended coastal zones, forecasts and estimates
can be done in parallel. Each time the simulated model wave reaches deep ocean
buoys or tidal gauge, expected values of wave parameters and inundation zones
are updated with historical events information and pre-calculated scenarios. The
Method of Splitting Tsunami (MOST) software package is used for mathematical
simulation.
The authors suggest code acceleration for deep water wave propagation. As a result,
performance is 15 times faster compared to MOST, original version. Performance gain is
achieved by compiler options, use of optimized libraries, and advantages of OpenMP parallel
technology. Moreover, it is possible to achieve 100 times code acceleration by using modern
Graphics Processing Units (GPU). Parallel evaluation of inundation zones for multiple
coastal zones is also available. All computer codes can be easily assembled under MS
Windows and Unix OS family. Although software is virtually platform independent,
the most performance gain is achieved while using the recommended hardware
components.
When the seismic event occurs, all valuable parameters are updated with seismic data and
wave propagation monitoring is enabled. As soon as the wave passes each deep ocean
tsunameter, parameters of the initial displacement at source are updated from direct
calculations based on original algorithms. For better source reconstruction, a combination of
two methods is used: optimal unit source linear combination from preliminary calculated
database and direct numerical inversion along the wave ray between real source and particular
measurement buoys. Specific dissipation parameter along with the wave ray is also taken into
account.
During the entire wave propagation process the expected wave parameters and
inundation zone(s) characteristics are updated with all available information. If
recommended hardware components are used, monitoring results are available in real
time.
The suggested version of CWTHM has been tested by analyzing seismic precursors
(foreshocks) and the measured tsunami waves at North Pacific for the Central Kuril’s
tsunamigenic earthquake of November 15, 2006. |
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