When the wind is blowing, what is the difference between the air pressure at the crest and at the trough of an ocean wave due to the Bernoulli effect?

Answer: Wind blowing over the water creates waves. The longer the distance over which the wind blows (the greater the “fetch”), the bigger the waves. There are two effects: the wind blows on the wave crests, exerting a force parallel to the wind direction due to air resistance, and there is a pressure differential between the wave crests, which experience the full wind speed, and the wave troughs, which do not.

If the wave is high enough, then the wave trough will experience a wind speed of zero. In that case, the pressure differential due to the Bernoulli effect will be

ΔP=12ρv2,

so we need to estimate the density and speed of the...

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