They found that gravity waves "break" on the surfaces of planes, just like ocean waves breaking on the beach, causing much of the turbulence that occurs out of the blue in clear air.

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We had to turn into the wind to get to him which meant we had waves breaking through the lifeboat.

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For a few minutes we sat there quietly, listening to the waves breaking.

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And then sounds of people relaxing, lovers relaxing on the beach and talking to one another and the sound of the wind blowing and the sea gulls and the waves breaking.

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They wanted to body surf where the waves were breaking.

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The cacophony of breaking waves is a distant rumble.

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"Waves were breaking out on the blue see, " Heyerdahl later wrote.

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