LinaHeart
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The waves in a lake are more calm and still compared to the waves in an ocean.
Waves are energy. Energy, not water, moves across the ocean's surface. Water particiles only travel in a small circle as a wave passes.
Most waves are caused by wind driving against water. When a breeze of two knots or less blows over calm water, small ripples form and grow as the wind speed increases until whitecaps, comprised of millions of tiny air bubbles, appear in the breaking waves. Waves may travel thousands of miles before rolling ashore and dissolving as surf.
A wave's size and shape reveals its origins. A steep, choppy wave out at sea is fairly young and was probably formed by a local storm. Slow, steady waves near shore which rear high crests, and plunge into foam come from far away, possibly another hemisphere. Lake waves do not travel as far.
No two waves are identical, but they all share common traits. Every wave, from a tiny ripple to a huge tsunami, has a measurable wave height, the vertical distance from its crest (high point) to its trough (low point). Wind speed, duration, and fetch (the distance it blows over open water) determine how high a wave grows. The maximum height in feet is usually one half or less the wind speed in miles per hour. Wave height decreases gradually as the wind dies and the wave approaches shore. When it touches bottom, it slows, the back overtakes the front, forcing it into a peak, curves forward, and dissolves into a tumbling rush of foam and water called a breaker.
The size of a wave depends on:
1. The distance the wind blows (over open water) aka "fetch"
2. The length of time the wind blows
3. The speed of the wind
The greater these three are the greater the wave is.
 Posted 162 days ago
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