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    Re: New Moon, Perigee, and Solstice
    From: Rodney Myrvaagnes
    Date: 2003 Dec 29, 17:53 -0500

    On Fri, 26 Dec 2003 11:15:26 +0000, Trevor J. Kenchington wrote:
    
    >
    >> In all these divisions, the general form of the differential equation
    >> would be the same. The number of terms and the numerical coefficients
    >> would be different. In each of them the forcing function is a boundary
    >> to a larger world. It is not something special, and cannot really be
    >> called a "cause" except in a local sense.
    >
    >
    >In the case of any one local area, I can see that. However, the tides of
    >the World Ocean are all interconnected and, seen as a whole, their
    >forcing function is gravitational, not water movements in some adjacent
    >basin. If non-zero "ages" of tides are widespread (albeit not
    >universal), then I would have expected some "cause" rooted in the energy
    >from the lunar and solar gravitational attraction. That seems, to me, to
    >be fundamentally different from the tides of the Minas Basin being
    >driven by the tides immediately outside Cape Split. Mathematically, it
    >may not be different but physically it seems so -- at least to me.
    >
    I need to get more about what the difference is between physical and
    mathematical before i could dream of answering this. Gravitational
    forces are different from water movement, but they are all connected,
    and the gravitation between moon, sun, and earth are, to me, just
    another boundary.
    
    >> A practical interface for this question would be tide tables for a
    >> mid-Pacific Island, such as Canton and Enderbury. That should give a
    >> good handle on the phase of the tidal bulge as it would be in a
    >> uniformly water-covered planet. I don't have such a tide table.
    >
    >
    >Neither do I but I don't think it would show what you expect. The tides
    >of the mid-Pacific are dominated by amphidromic systems just as much as
    >those of the North Sea are. They do not resemble a "tidal bulge" on a
    >planet that lacked land masses. (I'm not sure that a planet without land
    >would have recognizable bulges anyway, unless the ocean was also
    >extremely deep and covering a very small solid core.)
    >
    Myabe it wouldn't show the bulge. The bottom is anything but uniform.
    But I think the bulge would show in a quite recognizable form in an
    ocean over a sperical core, even if the ocean were as shallow as ours.
    The friction (hence, the "Q") would be different.
    
    
    
    
    Rodney Myrvaagnes                                                              
                          Opinionated old geezer
    
     "It is, of course, quite true that no great amount of skill is required to 
    navigate a ship most of the time, and
    on those less frequent occasions when a higher level of competence is 
    desirable luck may suffice. If that runs out there is always insurance..." 
    __The late Captain Richard Cahill
    
    
    

       
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