Title: Outline the transition of a deep-water wave to a shallow-water wave as it approaches shore. What ...
Post by: salsathief on Jan 23, 2018
Outline the transition of a deep-water wave to a shallow-water wave as it approaches shore. What will be an ideal response?
Title: Outline the transition of a deep-water wave to a shallow-water wave as it approaches shore. What ...
Post by: Wilkinson on Jan 23, 2018
Most wind waves eventually find their way to a shore and break, dissipating all their order and energy. The process begins with the transition of a deep-water wave to a transitional wave in water less than half a wavelength deep. (1) The wave train moves toward shore. When the depth of the water is less than half the wavelength, the wave feels bottom. (2) The circular motion of water molecules in the wave is interrupted. Circles near the bottom flatten to ellipses. The waves energy must now be packed into less water depth, so the wave crests become peaked rather than rounded. (3) Interaction with the bottom slows the wave. Waves behind it continue toward shore at the original rate. Wavelength therefore decreases, but period remains unchanged. (4) The wave becomes too high for its wavelength, approaching the critical 1:7 ratio. (5) As the water becomes even shallower, the part of the wave below average sea level slows because of the restricting effect of the ocean floor on wave motion. When the wave was in deep water, molecules at the top of the crest were supported by the molecules ahead (thus transferring energy forward). This is now impossible because the water is moving faster than the wave. As the crest moves ahead of its supporting base, the wave breaks. The break occurs at about a 3:4 ratio of wave height to water depth (that is, a 3-meter wave will break in 4 meters of water). The turbulent mass of agitated water rushing shoreward during and after the break is known as surf. The surf zone is the region between the breaking waves and the shore.
Title: Outline the transition of a deep-water wave to a shallow-water wave as it approaches shore. What ...
Post by: salsathief on Jan 23, 2018
Thank you for being my superhero!
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