Methods and Results of Experimental Studies of Ocean Tides

Direct measurements of tidal elevations are mainly performed at coastal and (comparatively few in number) island stations with the help of tide gauges or automatic level recorders. The accuracy of such measurements in approximately 1 cm. At present there exist some ten thousand stations, scores of them having accumulated continuous series of hourly elevation measurements of more than 50 years duration. Since 1964 deep-sea recording instruments with sensitive pressure transducers ensuring an accuracy of individual measurements of about 1 mm have been employed. The data deep-sea water-pressure measurements containing the values of harmonic tidal constants at 108 stations located in different parts of the World Ocean, and accumulated up to 1977, have been systematized by Cartwright et. al. [104].