Diffraction is a sudden change in the direction and intensity of waves after passing by a coastal feature or offshore obstruction. The obstacle will block a portion of the wave’s energy, forcing it to spread into the sheltered area behind the obstruction. For example, if a west or southwest swell reaches a south-facing surf spot with a curved shoreline, the energy of the waves will diffract – or bend – toward the protected or hidden area of the coastline.

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What is wave diffraction?

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