Geoscience Reference
In-Depth Information
Chapter 6
Methods of Tsunami Wave Registration
Abstract The traditional method for tsunami wave registration by coastal mare-
ographs including modern telemetric complexes, is described. The technique is de-
scribed for measuring tsunami waves in the open ocean with the aid of bottom
pressure sensors. The advantages of this technique are discussed. The technique
for studying and documenting effects of tsunami influence on the coast are briefly
expounded. The significance of searching for and identifying paleotsunami sedi-
ments is discussed. The application is described of satellite altimeters for registering
tsunamis in the open ocean, and data are also given concerning registration of the
26 December 2004 tsunami in the Indian Ocean by the JASON-1 satellite.
Keywords Tsunami registration
·
mareograph
·
sea level
·
bottom pressure
·
telemet-
ric complex
·
satellite communications
·
tide
·
DART
·
JAMSTEC
·
tsunami sensor
·
tsunami manifestation
·
tsunami run-up
·
run-up heights
·
tsunami deposit
·
ero-
sion
·
abrasion
·
inundation
·
topographic profile
·
paleotsunami
·
satellite altimetry
·
dispersion
·
wave front
The first information on the potential generation of a tsunami comes from the World
Seismic Network. Data on the time, epicentre coordinates and energy (magnitude)
of an underwater earthquake permit to estimate the location of the source, the prob-
ability for the tsunami to originate and the time the wave will arrive at the coast. But
tsunami waves are not related in a unique manner to a seismic event. A strong earth-
quake is sometimes accompanied by an insignificant tsunami, while, contrariwise,
a weak earthquake in a number of cases causes the formation of catastrophic waves.
For a more accurate estimation of the tsunami hazard, information is required on
the actual development of the wave process with time. In absence of such infor-
mation the existence of a great number of false alert signals and neglected tsunami
events is practically inevitable.
Tsunami registration is performed by various methods, including traditional mea-
surements of the sea level close to the coast (mareographs), measurements with
the aid of bottom pressure sensors in the open ocean, as well as methods, re-
cently undergoing development, of distance measurements, which primarily involve
