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Can you explain how waves can straigten an irregular coast line?
--- Annette, Regis University
Waves move energy. That's what they do. Wave energy in the ocean is affected by water depth. The energy cruises along just fine in the open ocean, where the water is deep and there isn't anything to interfere with the passage of the wave. But when the wave approaches a land mass, the wave begins to "feel the bottom" and the energy transfer is affected by friction. On an irregular coastline, the headlands get shallower first (before coves and pocket beaches), so extra wave energy is focussed there (due to refraction), increasing the erosional power of the waves. This also results in less energy being available in the coves and such, making them relatively lower energy depositional environments. The result? A straighter coastline as the headlands are beaten up and the pieces dumped into the coves.
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