Internal Waves in The Ocean
Most people think of waves as a surface phenomenon, which acts between water (as in lakes or oceans) and the air. Where low density water overlies high density water in the ocean, internal waves propagate along the boundary. They are especially common over the continental shelf regions of the world oceans and where brackish water overlies salt water at the outlet of large rivers. There is typically little surface expression of the waves, aside from slick bands that can form over the trough of the waves.
Internal waves are the source of a curious phenomenon called dead water, first reported by the Norwegian oceanographer Fridtjof Nansen, in which a boat may experience strong resistance to forward motion in apparently calm conditions. This occurs when the ship is sailing on a layer of relatively fresh water whose depth is comparable to the ship's draft. This causes a wake of internal waves that dissipates a lot of energy.
Read more about this topic: Internal Wave
Famous quotes containing the words internal, waves and/or ocean:
“Even if fathers are more benignly helpful, and even if they spend time with us teaching us what they know, rarely do they tell us what they feel. They stand apart emotionally: strong perhaps, maybe caring in a nonverbal, implicit way; but their internal world remains mysterious, unseen, “What are they really like?” we ask ourselves. “What do they feel about us, about the world, about themselves?””
—Augustus Y. Napier (20th century)
“Yet
I trust the sanity of my vessel; and
if it sinks, it may well be in answer
to the reasoning of the eternal voices,
the waves which have kept me from reaching you.”
—Frank O’Hara (1926–1966)
“your old fashioned tirade—
loving, rapid, merciless—
breaks like the Atlantic Ocean on my head.”
—Robert Lowell (1917–1977)