As wind-generated ocean swells travel from the open sea toward a shallow coastline, their physical characteristics change systematically due to interaction with the seabed. What is the correct chronological sequence of this wave transformation, starting from the open ocean and ending at the shoreline?
- 1Swells travel through deep water where water depth exceeds half their wavelength, moving without seafloor friction.
- 2The wave base encounters the rising seabed, causing the circular motion of water particles to flatten into ellipses.
- 3Frictional drag causes wave speed and wavelength to decrease while wave height rises sharply.
- 4The top of the wave outruns its slowed base, causing the crest to topple forward and break into surf.
Answer
The correct sequence begins with undisturbed deep-water wave propagation, followed by the wave base contacting the seafloor, wave shoaling with increasing height and decreasing speed, and ends with the crest collapsing to form breaking surf.
In open ocean water, waves behave as deep-water waves where particle motion does not touch the seafloor. When water depth decreases to less than half the wavelength, the wave base begins to drag along the seabed. This bottom friction slows the lower part of the wave, decreasing velocity and wavelength while pushing wave height upward (shoaling). Ultimately, the wave crest moves faster than its slowed base, causing the crest to collapse forward into breaking surf.
Step-by-Step Solution
Key Concept
Ocean Wave Shoaling and Coastal Breaking Dynamics
Estimated Time:1m 0s