|MadSci Network: Earth Sciences|
Tides can be thought of as waves that travel around an oceanic basin. If you draw lines of constant phase (or time at which high tide occurs), they meet at a hub where there is no tide (itís high- tide all the time, so the water level never changes). This hub is called an amphidromic point. If the basin were perfectly regular, the amphidromic point would be in the centre. The Atlantic is quite irregular. As it turns out, one of these amphidromic points is right on the edge of the Caribbean. See http:// svs.gsfc.nasa.gov/stories/topex/images/TidalPatterns_hires.tif.
For more on tides, check out the entry in Wikipedia .
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