Santa Cruz Tides
One of Nature’s wonders, over which the most obsessive control freak you know has absolutely no control, is the tide. That is because the changing tide at a given location is the result of the position of the sun and moon relative to the earth, the effects of the earth’s rotation, and local shape of the sea floor. All in all, the tide is a fairly complex phenomenon, not easily predicted, at least not in our heads. Tides must drive control freaks nuts. 
Wikipedia does a good job in the discussion of tides.
That which is not easily subject to human intuition or estimation is often the subject of modeling.
I often refer to a tide table calculated for Santa Cruz, CA by the folks at Scripps. (Note added January 16, 2010: Scripps has removed the tide table from the link that I had provided here.) Tide tables are helpful for finding the best times to visit tidal pools, for wading, or for prevention of getting trapped against coastal cliffs with a high tide coming in. If you often visit the Santa Cruz area, you may find that the link to the tide table comes in handy.
-Bill at Cheshire Cat Photo
