Geoscience Reference
In-Depth Information
There exist several promising ways for resolving the problem. One of them is
realized in the Japanese system of operative tsunami prognosis [Tatehata(1998);
Handbook for Tsunami Forecast (2001)]. The method is based on tsunami sources
exhibiting the property of recurrence. Therefore the problem, requiring long-time
calculations, has been resolved beforehand. The results of calculations are presented
in a special database. When a real underwater earthquake takes place, then in accor-
dance with its magnitude and epicentre location necessary data are extracted from
the database and used for calculating the possible run-up heights applying the inter-
polation method.
The second way consists in making use of deep-water sensors of tsunamis estab-
lished far from the coast (for instance, DART, JAMSTEC). The actual idea and its
first realization are related to the name of S. L. Soloviev. There exist various possi-
bilities for using such systems. One of them is based on the fact that timely registra-
tion of a wave permits to measure its characteristic (amplitude) with precision and
to correct inaccuracies in the calculation of the wave generation at the source.
The catastrophic tsunami that occurred in December 2004 in the Indian Ocean
was registered by a radio-altimeter established on the satellite JASON-1. Thus,
the good prospects became evident of methods involving satellite monitoring of
tsunamis.
Regretfully, the modern tsunami service is mainly based on regional principles.
Analysis of the actions taken by national services on December 26, 2004, revealed
their 'zones of responsibility' to be limited only to the sectors of the coast under
their control. Taking into account the restricted capabilities of certain developing
countries to provide operative tsunami warning at a modern level and, also, the scale
of such catastrophes, it seems expedient to create a global monitoring system of
the ocean's surface to function under international control. The authors of this topic
fully support the International Tsunami Information Center (ITIC, NOAA USA) in
its efforts aimed at the rapid as possible creation of a worldwide tsunami warning
system.
1.5 Databases and Tsunami Statistics
There exist several different informational resources containing the main informa-
tion on tsunamis. One of the most effective and in greatest demand is the historical
database for tsunamis in the Pacific Ocean, which was created in the Tsunami labo-
ratory of the Institute of Computational Mathematics and Mathematical Geophysics,
SB RAS (Novosibirsk) with support of UNESCO and the Russian Foundation for
Basic Research [Gusiakov (2001)]. The Internet version of the database is available
at http://tsun/sscc.ru/htdbpac.
The database contains information on approximately 1,500 tsunamigenic events
that occurred in the Pacific region (within the geographical boundaries 60
◦
S-60
◦
N,
80
◦
E-100
◦
W) during the entire historical period of observations (starting from
the year 47
BC
up to now). This database includes a large volume of coastal observa-
tions of tsunamis (about 9,000 records) as well as various auxiliary information on
