Tides

Data about tidal patterns accumulated in various parts of the world are used to produce tide tables. Tide tables are constructed by examining records to find out, for any given location, the times at which high and low tides have occurred in the past and the levels which those tides have reached. These records are then used to predict the most likely times and levels to be expected for tides at various times in the future for the same locations. Because of differences in ocean bottoms, coastline shape, and other factors, unique tide tables must be constructed for each specific coastline in the world.