In article ,
Chuck S. wrote:
Greg Neill wrote:

"Chuck S." wrote in message
...
I'm looking to incorporate the calculation of high and low tides
into my Delphi software. For this I need algorithms telling me how
to calculate the time of high and low tides. Do you know where I
can get such algorithms? I understand it will probably involve
complex calculations to find the position of the sun and moon in
relation to the earth and I am prepared for that.

Computing the position of the Sun and the Moon isn't that complex if
you settle for a modest accuracy. On my web site (URL below) you'll
find what I believe to be among the simplest possible algorithms for
computing solar and lunar positions with an accuracy of one minute of
arc, and that ought to be enough for tidal computations.

That will be but the beginning of the ordeal. Much of the
physics of the tides is in the interaction of the water with
the geometry of the coastlines. For example, large bays
cause resonance effects. The Bay of Fundy comes to mind.

I'm not looking to take bay action into account since I will
be calculating what I think are called "land tides". So does high
tide for a land mass appear as soon as the moon is overhead? Or is
there a delay of x minutes? What would x be?

There's definitely a delay, but I don't know how long the delay is.

Tidal computations of the oceans and the seas depend a lot on
empirical data. I believe computations of land tides would need
to depend on empirical data too, but I suppose there are much
less land tide data available.

For what purposes do you want to compute the land tides?

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