



Table 6. Coiiiparal 



ve tidi- 



tatioii 













Station 



Reference station 



NormaJixing 

 factor' 



MTL 



NOVO 



MLLW 



Ml.W 



MHW 



MHHW 



Record 



Interval for establishing 





Higlicst 



Lowest 



da turns 



AllanlicCily, NJ. 



Sandy llool^ 



M 



2.05 



1.70 



2 



0.00^ 



1. 10 







8.9 



-3.7 



1941 to 1959 



Naples, Kla. 



SI. Marks 



D 



1.05 



0.57 



-0.50 



0.00^ 



2.10 



2.30 



12.2 



-2.5" 



1966 to 1968 



Crescent City, Calif. 



Humboldt Bay 



D 



3.75 



3.63 



0.00* 



1.20 



6.30 



6.90 



10.0 



-2.9 



1934 to 1941 



Soutlibcach, Oreg. 



Humboldt Bay 



D 



4.50 



4.01 



o.oo' 



1.30 



7.60 



8.30 











1968 to 1973 



Fridjy Harbor, Wasli. 



Port Townsond 



D 



4.75 



4.42 



0.00* 



2.50 



7.00 



7.70 



10.9 



-3.9 



1941 to 1959 



'M = mean tidal range; D = diurnal tidal range. 

 Missing data. 

 'Local datum is MLW. 

 Estimated record. 

 *Local datum is MLLW. 



predictions inferred from the reference stations. Figures 1 and 2 are based on the output 

 obtained with this program. Hydrographs for all reference tide stations and a few others are 

 provided in Appendix B. The scale for each plot is adjusted to allow the extreme range of 

 the 19-year epoch to occupy the fuU vertical expanse of the graph. The reason is to show 

 the variable waveforms of the astronomical tide, not to provide quantitative data in 

 graphical form. The position of the datum planes MLLW, MLW, MSL, MHW, and MHHW is 

 shown on each graph as a measure of scale. The mean range, as indicated on the graph and as 

 tabulated in Appendix C, provides the vertical scale. In general, tlie changes in tide 

 hydrographs with distance along the shore are slow and continuous from Eastport, Maine, to 

 Galveston, Texas, and from San Diego, California, to Alaska. One notable exception is 

 Baltimore, Maryland, where the hydrograph resembles those for the Gulf of Mexico coast 

 more than those for nearby Atlantic coast locations. All predictions for the Atlantic and 

 gulf coasts in this set are for January 1963. AH hydrographs in Appendix B for the Pacific 

 coast are for January 1973. 



3. Graphs Displaying Other Tide Characteristics. 



A second version of the tide prediction program is used to prepare tide predictions for 19 

 successive calendar years to cover all periods up to and including 19 years (see Table 1). The 

 detailed output is suppressed in this version of tlie program, but the results are summarized 

 in statistical form. One form of the summary is shown in Figure 27 which gives the annual 

 and the 19-year (metonic) cycles for Sandy Hook, New Jersey. Plots A to H in Figure 27 

 are defined below. 



(a) Plot A shows the predicted annual cycle of mean water levels in feet as defined by 

 the monthly mean of the predicted tides as averaged over the 19-year period. 



(b) Plot B shows the predicted MSL for each year in the metonic cycle. The variability 

 in annual MSL cannot be predicted by any established procedure; therefore, the annual MSL 

 has been held at zero in these calculations. This constant plot is included only to emphasize 

 that long-term changes in sea level have not been considered in these calculations. 



62 



