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    Re: Navigating Around Hills and Dips in the Ocean
    From: Richard M Pisko
    Date: 2003 Aug 16, 23:07 -0600

    On Sat, 16 Aug 2003 11:11:42 -0300, Trevor J. Kenchington wrote:
    
    >While I agree with George that there would be no virtue in routing ships
    >around the hills and valleys created by gravity anomalies, in order to
    >save the energy cost of climbing the hill,
    ... there should be no energy expended following the equipotential
    surface at all ...
    
    >there _might_ be some benefit
    >in avoiding these other types of hills.
    <
    ... and the hull would sink deeper into the fresher water, which would
    change the flow characteristics even if the displaced water is of the
    same mass ...
    
    >I would suspect that it is at
    >most a minor consideration in vessel routing (avoiding of benefiting
    >from the Gulf Stream current would be of far greater concern than its
    >effect on elevation) but perhaps somebody takes it into account.
    >
    I think you hit on an important factor there, with the Gulf Stream
    current; and perhaps the expected wind patterns.  But again, except
    for the displacement of a plumb line (or rather, a theodolite level
    vial bubble) near a mountain range, this is all theory to me.
    
    
    --
    Richard ...
    
    
    

       
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