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OCEANOGRAPHY 10
W A V E S
https://www.youtube.com/watch?v=SE56mnT_l_k (Stuck in Tsunami)
https://www.youtube.com/watch?v=gLg6qxkQ94A (Teahupoo)
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Wave definition, types of waves, orbital waves
Why study waves?
Wave parts, anatomy of a wave
How waves begin, generating force, restoring force
Wave Speed: R=D/T or C=L/T, Celerity
Water motion in waves
Wave base, L/2
Deep water waves, intermediate and shallow water waves
Wind generated waves, H dependent on WfD
Wave types: Sea, Swell and Surf
Waves as they approach the shore: refraction, diffraction and reflection
Canyon divergence and headland convergence
Sea caves, arches and sea stacks
Wave generated currents: longshore and rip
Standing waves: nodes and antinodes, seiches
Catostrophic waves: storm surges and tsunamis
Mega tsunamis: know H, L and P of a typical seismic sea wave!
Internal waves
http://www.youtube.com/watch?v=oIx-bnYo6tA (Big Wave pics)
Santa Cruz Harbor Mouth
November 26th, 2009
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CO 10
Teahupoo Tahiti
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• Generating Force: any disturbing force that creates a
wave, such as the wind, a landslide entering the water or an
earthquake or a volcano.
• Restoring Force: force that returns a disturbed water
surface to the equilibrium level, such as surface tension or
gravity.
• Gravity Wave: water wave form in which gravity acts as the
restoring force; a wave with a wavelength greater than 1.5cm.
• Capillary Wave: waves with wavelengths less than 1.5cm
in which the primary restoring force is surface tension. Periods
less than 2 seconds
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Wave definition, types of waves, orbital waves
Why study waves?
Wave parts, anatomy of a wave
How waves begin, generating force, restoring force
Wave Speed: R=D/T or C=L/T, Celerity
Water motion in waves
Wave base, L/2
Deep water waves, intermediate and shallow water waves
Wind generated waves, H dependent on WfD
Wave types: Sea, Swell and Surf
Waves as they approach the shore: refraction, diffraction and reflection
Canyon divergence and headland convergence
Sea caves, arches and sea stacks
Wave generated currents: longshore and rip
Standing waves: nodes and antinodes, seiches
Catostrophic waves: storm surges and tsunamis
Mega tsunamis: know H, L and P of a typical seismic sea wave!
Internal waves
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Figure 9.12
Sample question:
Which of the following is not a deep water wave?
A. A wave with a wavelength of 10m in 6m of
water.
B. A wave with a wavelength of 15m in 8m of
water.
C. A wave with a wavelength of 3m in 2m of
water.
D. A wave with a wavelength of 8m in 3m of
water
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Miyazaki Ocean Dome, Japan (1993 – 2007)
In 1995, 1.25 million people visited
Artificial Reef in Great Britain
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Universal Sea State Code
The bow of this supertanker is 25 meters above the water
Figure 9.20a
“Ground Swell” vs ”Wind Swell”?
Essentially the same thing. Surfers differentiate them by Period.
If the period is ~10 seconds or more, they call it “Ground Swell”.
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