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:::The inclination of the moon's orbit to the ecliptic is slightly over 5°. Depending on the position of the moon's nodes, the inclination of the moon to the earth's equator (and the maximum tidal force) is at some point between 28.5°N and 28.5°S when the ascending node of the moon's orbit coincides with the vernal equinox (like it will do at about the summer solstice of june 2006; you'll notice at that time that at the days around new moon, the moon wil be '''very''' high above the horizon round midday). The inclination of the moon to the earth's equator (and the maximum tidal force) will be at some point between 18.5°N and 18.5°S when the ascending node of the moon's orbit coincides with the autumnal equinox (like it will do in about 9.3 years after june 2006). This is what is often called the 18.6 year cycle of the moon's orbit. You'll have noticed that the '''maximum''' inclination of the moon to the earth's equator varies from 18.5° (N or S) to 28.5° (N or S) over time.
:::The '''maximum''' tidal '''force''' due to the moon's gravitation will be between these boundaries. At present the maximum tidal force due to the moon will be between 28.5° N and 28.5° S. In about 9.3 years the maximum tidal force will be between the boundaries of 18.5° N and 18.5° S. But the actual tidal amplitude depends on many more factors than just the tidal force. Most important is the depth of the ocean basin. If a tidal wave travels from deep water into a shalow basin, the wave is slowed down but the amplitude increases. Also if the wave travels into a funnel shaped basin (like the English Channel or the Bay of Fundy) the amplitude increases much. It's only a coincidence that sea basins that fulfill such conditions are found in the higher latitudes. To think that the tidal amplitude is only a function of tidal force would be an enormous simplification of this quite complicated fenomenon. [[User:Wikiklaas|Wikiklaas]] 23:32, 13 March 2006 (UTC)
Amplitudes do not follow a definite pattern with latitude. For example the semi-diurnal amp in the Gulf of Carpentaria is some 8m. Long period tides Mf and Mm do show a lat dependency, though. The analytic solution by Kelvin is larger at greater lats. The cutoff lat for M2 is 71N/S, as the inertial period (half pendulum day) is shorter than the tidal frequency. Mf and Mm can exist at such low frequencies since they are mixture of long and short Rossby waves (Wunsch et al, Progr Oceanogr, 1997).
== Swapping the pictures ==
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