surflineのインスタグラム(surfline) - 8月21日 03時09分

The Importance of Swell Period.
Swell period is a key wave predictor and is defined as the time required for one complete wave length to pass a fixed point. Nearly all swell you’re likely to see will range from 4 to 22 seconds. Usually, the time is measured between two successive wave crests, but measuring from trough to trough would also yield the same result. Swell period is a defining characteristic of a swell, and a surfer who disregards swell period could find his/herself in surf that is disappointingly smaller or dangerously stronger than anticipated. For more information on swell period, hit the link in bio.
?: @billywatts

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