There are multiple listings for the same place, and they give different results. Whats going on?
There are two different approaches to predicting the tides at a given place. One approach is to calculate them directly from a data set; when this is done it is called a “reference station.” The other approach is to estimate them using adjustments to the tides at a nearby reference station; when this is done it is called a “subordinate station.” Data gathered from the NOAA web site sometimes include both a reference station and a subordinate station for the same place. For example, the subordinate station may be used for published tide tables while the reference station is still relatively new and untested. The results will differ, but they should be close (assuming that there are no problems with the data). If you are concerned about matching predictions up with those from some particular source, you should try each data set and see which one matches the best. In rare cases, data gathered from the NOAA web site include two reference stations or two subordinate stations with exactly th
