Geoscience Reference
In-Depth Information
Volume of inundation = Volume under the tsunami wave
Cross-sectional area
of coast inundated
Cross-sectional area under
the tsunami wave
=
Fig. 2.13
Schematic diagram showing that the cross-sectional area of coastline flooded, and volume of inundation by a tsunami is equal to the
cross-sectional area and volume of water under the tsunami wave crest. The landscape represented in this diagram will be described in
Chap. 4
three times higher than those calculated using this equation
(Yeh et al.
1994
). The velocity defined by Eq.
2.17
has the
potential to move sediment and erode bedrock, producing
geomorphic features in the coastal landscape that uniquely
define the present of both present-day and past tsunami
events. These signatures will be described in detail in the
following chapter.
100
10
1
0.1
0.0 1
0
10
20
30
40
50
References
Height at shore (m)
Fig. 2.14
Tsunami height versus landward limit of flooding on a flat
coastal plain of varying roughness. Roughness is represented by
Manning's n, where n equals 0.015 for very smooth topography, 0.03
for developed land, and 0.07 for a densely treed landscape. Based on
Hills and Mader (
1997
)
Anon.,
La
Manzanillo
Tsunami.
University
Southern
California
Tsunami
Research
Group
website
(2005),
Blong,
Volcanic
Hazards:
A
Sourcebook
on
the
Effects
of
Eruptions (Academic Press, Sydney, 1984)
B.A.
Bolt, W.L.
Horn,
G.A.
MacDonald,
R.F.
Scott,
Geological
a tsunami can be minimized on flat coastal plains by
planting dense stands of trees. For example, a 10 m high
tsunami can only penetrate 260 m inland across a forested
coastal plain where the trees have a diameter large enough
to withstand the high flow velocities without snapping.
Equation
2.2
indicates that the velocity of a tsunami
wave is solely a function of water depth. Once a tsunami
wave reaches dry land, wave height equates with water
depth and the following equations apply:
Hazards (Springer, Berlin, 1975)
M.J. Briggs, C.E. Synolakis, G.S. Harkins, D.R. Green, Laboratory
experiments of tsunami runup on a circular island. Pure. appl.
Geophys. 144, 569-593 (1995)
E. Bryant, Natural Hazards, 2nd edn. (Cambridge University Press,
Cambridge, 2005)
J.P. Caminade, D. Charlie, U. Kanoglu, S. Koshimura, H. Matsutomi,
A. Moore, C. Ruscher, C. Synolakis, T. Takahashi, Vanuatu
earthquake and tsunami cause much damage, few casualties. Eos
Trans. Am. Geophys. Union 81(641), 646-647 (2000)
F.E. Camfield, Tsunami effects on coastal structures. J.Coastal Res.
Spec. Issue No. 2, 177-187 (1994)
B.H. Choi, E. Pelinovsky, K.O. Kim, J.S. Lee, Simulation of the trans-
oceanic tsunami propagation due to the 1883 Krakatau volcanic
eruption. Nat. Hazards Earth Syst. Sci. 3, 321-332 (2003)
E.L. Geist, Local tsunamis and earthquake source parameters. Adv.
Geophys. 39, 117-209 (1997)
S. Harig, C. Chaeroni, W.S. Pranowo, J. Behrens, Tsunami simulations
on several scales. Ocean Dyn. 58, 429-440 (2008)
J.G. Hills, C.L. Mader, Tsunami produced by the impacts of small
asteroids. Ann. N. Y. Acad. Sci. 822, 381-394 (1997)
F. Imamura, A.C. Yalciner, G. Ozyurt, Tsunami modelling manual
(TUNAMI model) (2006),
http://www.tsunami.civil.tohoku.ac.jp/
K. Iida, T. Iwasaki (eds.), Tsunamis: Their Science and Engineering
(Reidel, Dordrecht, 1983)
H
t
¼
d
ð
2
:
16
Þ
v
r
¼
2 gH
ð
0
:
5
ð
2
:
17
Þ
where
v
r
= velocity of run-up (m s
-1
)
d = the depth of water flow over land (m)
This equation yields velocities of 8 s
-1
-9ms
-1
for a
2 m high tsunami wave at shore (Camfield
1994
). Where
tsunami behave as solitary waves and encircle steep islands,
velocities in the lee of the island have been found to be
