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Trevor,

I don't know any oceanographers to consult on this question, but
lacking anything to break spherical symmetry, I can't see how tides on
a spherical earth could be different in one place from another exactly
equivalent place. Phase would have to be tied to LHA of the sun and
moon, AFIK.

Perhaps I misunderstand your meaning.

On Tue, 30 Dec 2003 02:07:56 +0000, Trevor J. Kenchington wrote:

>Rodney,
>
>Of course the frequency of tidal waves is not affected by basin
>morphology (except where shallow-water effects produce assorted
>harmonics in addition to the tide at the frequency of the driving
>force). However, it is not only amplitude that is affected by real
>basins and would be by the seabed in a theoretical, global ocean of
>uniform depth. The phase angles are strongly affected also but, perhaps
>more important, so is the nature of the wave. In most areas, tides
>predominantly take the form of standing waves and very commonly Kelvin
>waves (thus forming amphidromic systems), rather than progressive waves
>heading in a westerly direction around the globe.
>
>That is true in the real Southern Ocean (which is open clear around all
>360 degrees of longitude, with a relatively constant depth) as it is in
>the open expanses of the real Pacific Ocean. As best as I can comprehend
>the conclusions of tidal specialists, it would also be true of the
>hypothetical global ocean too.
>
>
>Trevor Kenchington
>
>
>
>You wrote:
>
>
>> The depth would certainly have an effect on surface waves as you say,
>> but it would affect the amplitude, not the frequency. The solution
>> would still be at the frequency of the driving force in the steady
>> state.
>>
>> That is the actual case now, with all the extra complications. It would
>> not be less so if the complications were removed.
>
>
>--
>Trevor J. Kenchington PhD                         Gadus@iStar.ca
>Gadus Associates,                                 Office(902) 889-9250
>R.R.#1, Musquodoboit Harbour,                     Fax   (902) 889-9251
>Nova Scotia  B0J 2L0, CANADA                      Home  (902) 889-3555
>
>                     Science Serving the Fisheries
>                      http://home.istar.ca/~gadus
>
>



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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