Geoscience Reference
In-Depth Information
speed
C
1
C
2
C
3
mean
sea level
d
1
d
2
d
3
depth
C
1
>C
2
>C
3
d
1
>> d
2
>> d
3
wave height increases shoreward
and energy flux is therefore conserved
A) Shoaling
60 m
20
m
B) Wave refraction
harbor
ocean
C) Wave diffraction
Schematic diagrams of wave behavior in shallow water, A) shoaling, B) refraction, and C) diffraction.
Fig. 8.3
because of its larger mass, exerts more energy against
you than the greyhound. A greyhound can move fast
and, when it hits you, you are bowled over. An elephant
moves slowly and, when it hits you, you move easily out
of its way. Here, the greyhound has more power than
an elephant (unless of course the elephant decides to
charge). Power as defined here applies to an infinite
train of waves.
Wavelength is much greater than wave height, so
that most of a wave's energy and power is controlled by
wavelength, which is related to the wave period.
However, a change in wave height has a much more
dramatic affect on changing wave energy and power
than a change in wavelength. Table 8.1 illustrates this
effect for the most common wave periods in swell
environments. (Note that these values would be
